National Instruments RMX-4120, RMX-4121, RMX-4122, RMX-4124, RMX-4125 User Manual

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RMX

RMX Programmable Power Supplies User Manual

RMX-4120 RMX-4121 RMX-4122 RMX-4123 RMX-4124 RMX-4125 RMX-4126 RMX-4127

RMX Programmable Power Supplies User Manual

February 2017 375744C-01

About the RMX User Manual

This manual is intended for users of the Regulated DC Power Supply and their instructors. It is assumed that the reader has knowledge about electrical safety standards and the electrical aspects of regulated DC power supplies.

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Chapter 1 Installation and Preparation

Attaching the Connector Cover ........................................................................................ 1-1

Connecting the Power Cord.............................................................................................. 1-1

RMX-4120/4121/4122/4123 (750 W Models)......................................................... 1-2

Necessary Cable ............................................................................................... 1-2

RMX-4124/4125/4126/4127 (1500 W Models)....................................................... 1-2

Necessary Cable ............................................................................................... 1-3

Switchboard Breaker Requirements ................................................................. 1-3

Connection Procedure............................................................................................... 1-4

Turning the Power On ...................................................................................................... 1-6

Turning the POWER Switch On .............................................................................. 1-6

Inrush Current................................................................................................... 1-7

Turning the POWER Switch Off .............................................................................. 1-7

Rack Mounting ................................................................................................................. 1-8

Load Considerations ......................................................................................................... 1-8

Loads with Peak Current or Pulse-Shaped Current.................................................. 1-8

Loads that Generate Reverse Current to the Power Supply ..................................... 1-9

Loads with Accumulated Energy ............................................................................. 1-9

Load Cables ...................................................................................................................... 1-10

Protecting Against Noise .......................................................................................... 1-11

Cabling Considerations When Using Remote Sensing ............................................ 1-11

Connecting to the Output Terminals ................................................................................ 1-12

Attaching the Output Terminal Cover ...................................................................... 1-15

Sensing.............................................................................................................................. 1-17

Local Sensing ........................................................................................................... 1-19

Remote Sensing ........................................................................................................ 1-19

Connecting an Electrolytic Capacitor Across the Load.................................... 1-22

Inserting a Mechanical Switch Between the RMX Programmable

Power Supply and the Load.............................................................................. 1-22

Accessories ....................................................................................................................... 1-23

Parallel Operation Signal Cable ............................................................................... 1-23

Chapter 2 Basic Functions

Measured Value Display and Setting Display .................................................................. 2-1

Measured Value Display .......................................................................................... 2-1

Power Display................................................................................................... 2-1

Setting Display ......................................................................................................... 2-2

Overvoltage Protection and Overcurrent Protection Setting Display....................... 2-2

System Configuration Setting Display ..................................................................... 2-2

Panel Operations............................................................................................................... 2-3

Contents

Measured Value Display, Setting Display, and Set OVP/OCP Display...................2-3

Fine Adjustment................................................................................................ 2-3

Output Operations............................................................................................................. 2-3

Output State at Power-up .......................................................................................... 2-4

Operation Overview.......................................................................................................... 2-4

CV Power Supply and CC Power Supply.........................................................................2-7

Crossover Point................................................................................................. 2-8

CV Mode and CC Mode Operation Examples .........................................................2-8

Example 1 .........................................................................................................2-8

Example 2 .........................................................................................................2-8

Using the RMX Programmable Power Supplies as a CV or CC Power Supply ..............2-9

Protection Functions and Alarms......................................................................................2-11

Alarm Occurrence and Clearing Alarms ..................................................................2-12

Alarm Occurrence............................................................................................. 2-12

Clearing Alarms................................................................................................2-13

Alarm Signal ..................................................................................................... 2-13

Protection Function Activation ................................................................................. 2-14

Setting limitation functions...............................................................................2-14

CONFIG Settings.............................................................................................................. 2-20

Specifying CF01 to CF36, CF 41 to CF52 CONFIG Settings.......................... 2-24

Specifying CF00/CF40 CONFIG Settings ....................................................... 2-25

CONFIG Parameter Details .............................................................................. 2-25

Preset Memory Function................................................................................................... 2-39

Saving Settings to Preset Memory............................................................................2-39

Recalling Preset Memory Entries ............................................................................. 2-40

Locking Panel Operations (Key Lock) .............................................................................2-41

Bleeder On/Off Feature .................................................................................................... 2-41

Fall Time................................................................................................................... 2-44

Switching from Remote Mode to Local Mode ................................................................. 2-44

Factory Default Settings (Initialization) ........................................................................... 2-45

Chapter 3 External Control

Overview........................................................................................................................... 3-1

About the J1 Connector ....................................................................................................3-1

Attaching the J1 Cable Core ..................................................................................... 3-2

About the J2 Connector ....................................................................................................3-5

Output Terminal Insulation............................................................................................... 3-7

When the Output Terminal is Not Grounded (Floating)........................................... 3-7

When the Output Terminal is Grounded................................................................... 3-9

Cautions When Controlling the Output with an External Voltage (Vext)................ 3-11

Controlling the Output Voltage ........................................................................................ 3-12

Control Using an External Voltage (Vext) ............................................................... 3-12

External Voltage (Vext) Connection ................................................................ 3-13

Control Using an External Resistance (Rext) ........................................................... 3-13

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RMX Programmable Power Supplies User Manual

External Resistance (Rext) Connection............................................................ 3-14

Controlling the Output Current......................................................................................... 3-14

Control Using an External Voltage (Vext) ............................................................... 3-15

Control Using an External Resistance (Rext) ........................................................... 3-16

External Resistance (Rext) Connection............................................................ 3-16

Controlling the Output On and Off States ........................................................................ 3-17

External Contact Connection.................................................................................... 3-18

Long-Distance Wiring ...................................................................................... 3-18

Controlling Output Shutdown .......................................................................................... 3-19

Output Shutdown Connection .................................................................................. 3-19

Long-Distance Wiring ...................................................................................... 3-20

Controlling the Clearing of Alarms .................................................................................. 3-20

Alarm Clear Connection ........................................................................................... 3-21

Long-Distance Wiring ...................................................................................... 3-22

External Monitoring ......................................................................................................... 3-22

Monitor Output Rating ............................................................................................. 3-22

External Monitoring of the Operation Status ................................................... 3-23

Chapter 4 Parallel/Series Operation

Master-Slave Parallel Operation....................................................................................... 4-1

Features of the RMX Programmable Power Supplies During

Master-Slave Parallel Operation............................................................................... 4-1

Voltage Display and Current Display............................................................... 4-1

Connection (Master-Slave Parallel Operation)......................................................... 4-3

Connecting the Signal Cables (Parallel Operation).......................................... 4-3

Connecting the Load (Parallel Operation) ........................................................ 4-4

Settings (Master-Slave Parallel Operation) .............................................................. 4-6

Setting the Master Unit, the Slave Units, and the Number of Units in

Parallel Operation (Including the Master Unit) ................................................ 4-6

Setting the Voltage and Current ....................................................................... 4-6

Setting the Overvoltage Protection (OVP) and Overcurrent Protection (OCP)

of the Master Unit............................................................................................. 4-6

Starting Master-Slave Parallel Operation ................................................................. 4-7

Turning Power On ............................................................................................ 4-7

Turning Power Off............................................................................................ 4-7

Series Operation ............................................................................................................... 4-8

Features of the RMX Programmable Power Supplies During Series Operation...... 4-8

Voltage Display and Current Display............................................................... 4-8

External Control ............................................................................................... 4-8

External Monitoring ......................................................................................... 4-8

Remote Sensing ................................................................................................ 4-9

Alarm ................................................................................................................ 4-10

Connection (Series Operation) ................................................................................. 4-10

Connecting the Load (Series Operation) .......................................................... 4-10

Contents

Settings (Series Operation) ....................................................................................... 4-11

Setting the Voltage and Current........................................................................ 4-11

Setting the Overvoltage Protection (OVP) and Overcurrent Protection (OCP).. 4-11

Starting (Series Operation) .......................................................................................4-11

Turning the Power On and Off ......................................................................... 4-11

Turning the Output On and Off ........................................................................ 4-11

Chapter 5 Maintenance

Calibration Overview........................................................................................................ 5-1

Calibration Procedure ....................................................................................................... 5-1

Installation ................................................................................................................ 5-1

Launch ...................................................................................................................... 5-1

Calibration Items....................................................................................................... 5-2

Basic Instructions...................................................................................................... 5-3

Save Calibration........................................................................................................ 5-3

Backup Calibration Data to a XML File...........................................................5-3

Send Calibration Data from a XML File .......................................................... 5-3

Revision History ............................................................................................... 5-3

System Requirements ....................................................................................... 5-4

Hardware Requirements ...................................................................................5-4

Environment......................................................................................................5-4

Cleaning ............................................................................................................ 5-4

Connection ................................................................................................................5-5

Appendix A Specifications

Appendix B Troubleshooting

Appendix C NI Services

Index

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Installation and Preparation

This chapter describes how to turn on an RMX programmable power supply, what kind of load cables to use, and how to connect cables to the output connectors.

Note Protection provided by this equipment may be impaired if it is used in a

manner not described in the manual.

Attaching the Connector Cover

RMX programmable power supplies are supplied with a connector cover that fits over the entire sensing, J1, and J2 connectors. For safety reasons, be sure to attach the connector cover when you use the RMX programmable power supply.

Figure 1-1. Connector Cover

Connecting the Power Cord

This product is a piece of equipment that conforms to IEC Overvoltage Category II (equipment that consumes energy supplied from a fixed installation).

A power cord is not included with the RMX-4124/4125/4126/4127. Use a power cord that conforms to this product’s rated AC input voltage, input current, and configured for the plug type. Refer to your product specifications for details.

Caution Risk of electric shock. This product is a piece of equipment that conforms

to IEC Safety Class I (equipment that has a protective conductor terminal). Be sure to earth ground the product to prevent electric shock. The product is grounded through the power cord ground wire. Connect the protective conductor terminal to earth ground.

Chapter 1 Installation and Preparation

RMX-4120/4121/4122/4123 (750 W Models)

Necessary Cable

• North America—Extra Hard Usage Cord, min. 300 V, 60 C, 14 AWG, 3 Conductor cord,

3 m or less, with a NEMA 5-15P to C14.

• Europe—HAR Marked, min. 300 V, 60 C, 2.5mm2, 3 Conductor cord, 3 m or less, with a

plug configured for the country of use to C14.

• International—Certified for country of use, min. 300 V, 60 C, 2.5mm

3 m or less, with a plug configured for the country of use to C14.

The power cord can be used to disconnect the RMX programmable power supply from the AC power line in an emergency. Connect the plug to an easily accessible power outlet so that the plug can be removed from the outlet at any time. Be sure to provide adequate clearance around the power outlet.

1. Check that the AC power line meets the nominal input rating of the product. The product

can receive a nominal line voltage in the range of 100 VAC to 240 VAC at 50 Hz or 60 Hz.

2. Check that the POWER switch is turned off.

3. Connect the power cord to the AC inlet on the rear panel.

4. Insert the power plug into a grounded outlet.

, 3 Conductor cord,

RMX-4124/4125/4126/4127 (1500 W Models)

Caution Risk of electric shock. Before you connect the power cord, turn off the

switchboard breaker (a switch that cuts off the power supply from the switchboard).

Risk of fire. Connection to the switchboard must be performed by a person who has knowledge about electrical safety standards and the electrical aspects of regulated DC power supplies. The switchboard breaker must meet the requirements shown below.

Caution Inside the product, protective circuits are connected to match the polarity

of the input terminal. Be sure to connect the L, N, and (GND) terminals of the product to the matching terminals on the switchboard.

In an emergency, turn off the switchboard breaker to disconnect the product from the AC power line.

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RMX Programmable Power Supplies User Manual

RMX-4125

Switchboard

Breaker indication example

For the

RMX-4125 only

30 A

Power cord

RMX-4125 dedicated breaker

Necessary Cable

• Vinyl cabtire cable (VCTF): Nominal cross-sectional area 5.5 mm2, 3 core

• Finished diameter: 10.5 to 14.4 mm in diameter

• Rated voltage: 250 V or higher

• Input terminal end: 14 mm of insulation stripped from conductor for the L and N wires. Crimping terminal: (round, M4) that fixes the cable insulation in place for the GND wire

• Length: 3 m or less

Switchboard Breaker Requirements

• Installation must be done in accordance with national wiring rules, such as NFPA 70 "NEC"

and CSA C22.1 "CEC".

• Rated current: 30 A (for safety, breakers whose rated current exceeds 30 A cannot be used)

• Do not power any other equipment from the switchboard breaker.

• Keep the breaker readily accessible at all times.

• Indicate that the breaker is dedicated for use with this product and that it is used to

disconnect the product from the AC power line.

Figure 1-2. Switchboard Diagram

Chapter 1 Installation and Preparation

Crimping terminal (round, M4)

When crimping the core wire, use a crimping terminal and tool that can also grip the insulation.

Connection Procedure

1. Check that the AC power line meets the nominal input rating of the product. The product can receive a nominal line voltage in the range of 100 VAC to 240 VAC at 50 Hz or 60 Hz.

2. Check that the POWER switch is turned off.

3. Attach a crimping terminal to the GND wire.

Figure 1-3. Attaching the Crimping Terminal

4. Connect the power cord and the included INPUT terminal cover to the AC INPUT terminal on the rear panel. Be sure to connect the AC INPUT L, N, and (GND) terminals correctly. Pass the power cord through the INPUT terminal cover, and fix the cord in place using the cable gland.

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RMX Programmable Power Supplies User Manual

STRIP-GAUGE

14 mm

Correct

Incorrect

The stripped wire is touching the chassis.

The wire strands are touching the chassis.

INPUT terminal cover

AC INPUT terminal

L: Black or brown

N: White or blue

(GND)

Screw

: Green or green and yellow

Power cord

Screw

Use this screw to fix the wire in place.

Screw M4

Remove the first 14 mm of the wire’s covering, and then insert the wire here.

AC INPUT terminal

Cable gland: Turn left to unlock

Cable gland: Turn right to lock

Cable gland: Supports wires from 10.5 to 14.4 mm in diameter

Figure 1-4. Connecting the Power Cord

5. Attach an appropriate crimping terminal to the switchboard end of the power cord.

6. Turn off the switchboard breaker.

7. Connect the L, N, and (GND) wires of the power cord to the matching terminals on the switchboard.

Chapter 1 Installation and Preparation

Turning the Power On

Turning the POWER Switch On

Caution Risk of electric shock. Regardless of whether load cables are connected to

the output terminals, be sure to attach the OUTPUT terminal cover before turning the POWER switch on.

You can use the CONFIG settings to set how the RMX programmable power supplies start when you turn the POWER switch on. Depending on the setting, the output may be turned on automatically when the POWER switch is turned on. If you connect a load without setting OVP and OCP to appropriate values, the load may be damaged if the output is programmed to automatically turn on when the power is switched on.

When you turn the POWER switch on for the first time after purchase, the RMX programmable power supply will be programmed with its factory default settings. Refer to Chapter 2, Factory

Default Settings (Initialization), for more information about these settings. Each subsequent

time you turn the power supply on, it starts with the panel settings (excluding the output on/off setting) that were in use immediately before the POWER switch was turned off.

You can use the CONFIG setting CF02 to select how the RMX programmable power supply starts when the POWER switch is turned on. Refer to Chapter 2, CF02 Power-on Status

Parameter, for more information about this setting.

1. Check that the power cord is connected correctly.

2. Check that the OUTPUT terminal cover is attached. Refer to the Attaching the Output

Terminal Cover section for more information about attaching the terminal cover. When the

product is shipped from the factory, the OUTPUT terminal cover is not attached.

3. Turn the POWER switch on. All the LEDs light, and then the voltmeter and the ammeter display the following sequence of information: the rated voltage and rated current, the firmware version number, the build number, and then the selected interface. Each item is displayed for approximately 1 second. After a few seconds, the RMX programmable power supply enters the operation standby state during which the output value is displayed.

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RMX Programmable Power Supplies User Manual

Figure 1-5. Power On Information Display

Inrush Current

When the POWER switch is turned on, an inrush current of up to 70 A can momentarily flow into the rear AC input of the programmable power supply. Check that sufficient current capacity is available in the AC power line or the switchboard, particularly if you are using multiple RMX programmable power supplies and turning on their POWER switches simultaneously.

Turning the POWER Switch Off

Flip the POWER switch to the side to turn RMX programmable power supplies off. The RMX programmable power supplies save the panel settings (except the output on/off setting) that were in use immediately before the POWER switch was turned off.

You can use CONFIG settings CF02 to select how the RMX programmable power supply starts when the POWER switch is turned on. Refer to Chapter 2, CF02 Power-on Status Parameter, for more information about this setting.

If the POWER switch is turned off immediately after the settings have been changed, the last settings may not be stored.

Caution After you turn the POWER switch off, wait at least 10 seconds after the

panel display turns off before you turn the POWER switch back on. Repeatedly turning the POWER switch on and off at short intervals can cause damage to the inrush current limiter. Furthermore, this will shorten the service life of the POWER switch and the internal input fuse.

Chapter 1 Installation and Preparation

Load current with peaks Pulse-shaped load current

Set constant current Ammeter reading (mean value)

Rack Mounting

You can use brackets or slide rails to mount the RMX programmable power supply to a rack.

When you mount an RMX programmable power supply to a rack, install the optional support angles (NI P/N) to support the device.

NI recommends that you keep all pieces that you remove from a RMX programmable power supply during installation. You will need these pieces if you remove the device from a rack.

When using several RMX programmable power supplies together for master-slave parallel or series operation, mount them to a rack before use.

Load Considerations

Note The output can become unstable if the following types of loads are connected.

Loads with Peak Current or Pulse-Shaped Current

The front panel of the RMX power supply only displays averaged voltage and current values. If the supply is connected to a load that draws current in spikes or pulses it is possible that the front panel will display a current reading lower than the programmed current setpoint. In reality, the spikes or pulses in the load current are exceeding the programmed current setpoint causing the supply to switch instantaneously into constant-current mode and causing the output voltage to drop.

For these types of loads, you must increase the set constant current or increase the current capacity.

Figure 1-6. Loads with Peak Current or Pulse-Shaped Current

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RMX Programmable Power Supplies User Manual

Equivalent circuit of the RMX-4122

Regenerative load

＋

Reverse current

-IO

+IO

Irp

RD (in Ω) ≤

RD: Reverse current bypass dummy load E

O: Output voltage

Irp: Maximum reverse current

EO (in V)

Irp (in A)

Load

Output current

Loads that Generate Reverse Current to the Power Supply

RMX programmable power supplies cannot sink reverse current from the load. Therefore, if a regenerative load (such as an inverter, converter, or transformer) is connected and tries to sink power into the terminals of the power supply, the output voltage will increase and can become unstable. This can cause a malfunction.

For these types of loads, connect a resistor (R

) as shown in the following figure to bypass the

reverse current. However, the amount of current to the load decreases by Irp.

Figure 1-7. Loads with Accumulated Energy

Caution Use a resistor with sufficient rated power for R

. If a resistor with

insufficient rated power for the circuit is used, the resistor will burn out.

Loads with Accumulated Energy

Connecting a load with accumulated energy, such as a battery, to an RMX programmable power supply may cause current to flow from the load to the internal circuit. This current may cause damage or reduce the life of the load.

For this type of load, connect a reverse-current-prevention diode (D programmable power supply and the load in series as shown in the following figure.

) between the RMX

This cannot be used in conjunction with remote sensing.

RMX-4122

Figure 1-8. Loads with Accumulated Energy

Load with accumulated energy

DRP: Reverse-current-protection diode

Chapter 1 Installation and Preparation

Caution To protect the load and the RMX programmable power supplies, use a D

that conforms to the following specifications.

• Reverse voltage withstand capacity–At least twice the rated output voltage of the RMX programmable power supply.

• Forward current capacity–Three to ten times the rated output current of the RMX programmable power supply.

• A diode with small loss.

• Be sure to take into account the heat generated by D

. DRP will burn out with inadequate

heat dissipation.

Load Cables

Caution Risk of fire. Use load cables whose capacity is adequate for the

RMX programmable power supply’s rated output current. The output connector and its surrounding area become hot. Use cables whose covers have heat resistance at 85 °C and higher.

Caution Risk of electric shock. Use the cable which has higher withstanding

voltage than the specified insulation voltage of the product to secure the double insulation or reinforced insulation.

The current capacity of a load cable is dependent on the maximum allowable temperature of the cable's insulation.

A cable’s temperature is determined by the resistive loss based on the current, the ambient temperature, and the cable’s external thermal resistance. The following table shows the current capacity of heat-resistant vinyl wires that have a maximum allowable temperature of 60 °C, assuming that a wire is stretched out horizontally in air in an ambient temperature of 30 °C. The current capacity must be reduced under certain conditions, such as when vinyl cables that have a low heat resistance are used, when the ambient temperature is 30 °C or greater, or when cables are bundled together and little heat is radiated.

Table 1-1. Current Capacity of Heat-resistant Vinyl Wires

Nominal

Cross-sectional

Area

2 mm

3.5 mm

5.5 mm

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AWG (Reference

Cross-sectional

Area)

Allowable

Current

(Ta = 30 °C)

Recommended

Current

14 (2.08 mm2) 27 A 10 A

12 (3.31 mm2) 37 A —

10 (5.26 mm2) 49 A 20 A

RMX Programmable Power Supplies User Manual

Table 1-1. Current Capacity of Heat-resistant Vinyl Wires (Continued)

Nominal

Cross-sectional

Area

8 mm

14 mm

22 mm

30 mm

38 mm

50 mm

60 mm

80 mm

100 mm

125 mm

150 mm

200 mm

AWG (Reference

Cross-sectional

Area)

Allowable

Current

(Ta = 30 °C)

Recommended

Current

8 (8.37mm2) 61 A 30 A

6 (13.3 mm2) 88 A 50 A

4 (21.15 mm2) 115 A 80 A

2 (33.62 mm2) 139 A —

1 (42.41 mm2) 162 A 100 A

1/0 (53.49 mm2) 190 A —

2/0 (67.43 mm2) 217 A —

3/0 (85.01 mm2) 257 A 200 A

4/0 (107.2 mm2) 298 A —

— 344 A —

— 395 A 300 A

— 469 A —

Protecting Against Noise

When connecting wires that have the same heat resistance, separating the wires as much as possible to increase heat radiation enables a greater amount of current to flow. However, wiring the + (positive) and - (negative) output wires of the load cable side by side or bundling them together will minimize unwanted noise on the output. The currents shown in Table 1-1 are allowable currents that have been reduced in consideration of the potential bundling of load cables. Use these values as a guideline when connecting load cables.

Cabling Considerations When Using Remote Sensing

As you increase the current setpoint or increase the resistance of your load cabling, the voltage drop between the RMX power supply and your load will increase. This results in the voltage at your load being smaller than the programmed voltage setpoint. Refer to Appendix A,

Specifications, to see the maximum voltage drop each RMX power supply's remote sense

terminals can compensate for. If the voltage drop exceeds this level, use shorter load cables or cables with a greater cross-sectional area.

Chapter 1 Installation and Preparation

- (negative) terminal + (positive) terminal

Chassis terminal

Connecting to the Output Terminals

Caution Risk of electric shock. Turn the POWER switch off before you touch the

OUTPUT terminals. Even if you turn the output off or turn the POWER switch off, if the bleeder on/off setting (CF11) is set to “OFF,” the voltage that was present when the output was on will remain at the output terminals. Turn the bleeder circuit on before you touch the output terminals. Regardless of whether load cables are connected to the output terminals, be sure to attach the OUTPUT terminal cover before turning the POWER switch on. Confirm that the voltage between any output terminal and ground is lower than the isolation voltage of the RMX programmable power supply.

Figure 1-9. RMX-4125 Output Terminal

1. Turn the POWER switch off. Check that there is no voltage across the output terminals.

2. Connect one end of the included chassis connection wire to the chassis terminal, and then connect the other end of the wire to the negative or positive output terminal.

Note For safety reasons, connect one of the output terminals to the chassis terminal

unless your application requires the output terminals to be floating.

Use the screw on the RMX to connect the wire to the chassis terminal. Use the screw on the output terminal to connect the wire to the output terminal.

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RMX Programmable Power Supplies User Manual

Chassis connection wire

Screw (M3)

Screw (M4) Chassis connection wire

Screw (M3)

Screw (M4)

Figure 1-10. RMX-4120/4121/4124/4125

Figure 1-11. RMX-4122/4123/4126/4127

3. Attach crimping terminals to the load cables.

The output terminals have holes for connecting the load cables. Use crimping terminals that are appropriate for the bolts that you are using.

4. Use the included bolt set to connect the load cables to the output terminals.

Connect the positive cable to the positive output terminal and the negative cable to the negative output terminal. The orientation of the crimping terminals will vary depending on the wire diameter of the load cables used.

Chapter 1 Installation and Preparation

Spring washer

Washer

Nut

Bolt (M8)

Crimping terminal

Attach the cable to the inner side

of the crimping terminal.

Attach the cable to the outer side of the crimping terminal.

Spring washer

Washer

Nut

Bolt (M5)

Screw (M4)

Figure 1-12. Connection Using M8 Bolt Set for RMX-4120/4121/4124/4125

Figure 1-13. Connection Using M5 Bolt Set for RMX-4122/4123/4126/4127

Crimping terminal

Note If you do not connect load cables in the correct orientation, you will not be

able to attach the OUTPUT terminal cover.

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RMX Programmable Power Supplies User Manual

line up the half of the cover.

Attaching the Output Terminal Cover

You can adjust the diameter of the holes that the load cables pass through by changing the positions in which the top and bottom halves of the OUTPUT terminal cover are put together.

There are two available positions. Use the appropriate position for the load cables that you are using.

• For cables that are up to 10 mm in diameter: Put the top and bottom halves of the OUTPUT terminal cover together so that the hole diameter is small.

• For cables that are between 10 mm and 18 mm in diameter: Put the top and bottom halves of the OUTPUT terminal cover together so that the hole diameter is large.

1. Remove the screw that is attached next to the output terminals on the RMX. Use this screw to attach the OUTPUT terminal cover.

2. Place the bottom half of the OUTPUT terminal cover underneath the load cables connected to the output terminals.

Figure 1-14. Attaching Bottom Half of the OUTPUT Terminal Cover

emove the screws, and then

Note The top and bottom halves of the OUTPUT terminal cover have different

shapes.

3. Align the tabs of the top half of the OUTPUT terminal cover with those of the bottom half. Align the tabs of the OUTPUT terminal cover according to the load cable diameter.

Chapter 1 Installation and Preparation

Top half of the cove

Align the protrusion of the top half of the cover with the top section of the protrusion of the bottom half.

Bottom half of the cover

For thick load cables

Cover hole diameter: 10 mm to 18 mm

Cover hole diameter: Up to 10 mm

For thin load cables

Top half of the cover

Align the protrusion of the top half of the cover with the middle section of the protrusion of the bottom half of the cover.

Bottom half of the cover

Middle section

Top section

After you have lined up the top and bottom halves of the cover, use the screws to fix the cover in place.

Screws (M3)

Figure 1-15. Aligning Both Halves of the OUTPUT Terminal Cover

4. Push the OUTPUT terminal cover against the rear panel, and then use the RMX screws to fix the cover in place. Ensure that the screws are securely fastened.

Figure 1-16. Attaching the OUTPUT Terminal Cover

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RMX Programmable Power Supplies User Manual

Sensing

When RMX programmable power supplies are shipped from the factory, the connector is attached to the sensing terminals. RMX programmable power supplies are supplied with a connector cover that fits over the entire sensing, J1, and J2 connectors. For safety reasons, be sure to attach the connector cover when you use the RMX programmable power supply. If they are damaged or lost, contact National Instruments.

Figure 1-17. Connector Cover

Figure 1-18. Terminal Connector

Caution Risk of electric shock and damage to internal circuits.

Never wire the sensing terminals while the POWER switch is turned on.

Use sensing cables that provide reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply. For uncovered sections of the shielded cables, use insulation tubes to secure reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply.

The sensing terminals are at approximately the same electric potential as the negative output terminal. Insert the cables so that the wire strands do not touch the chassis when they stick out of the sensing terminal. Also, insert the cables so that the stripped wires do not stick out of the terminal.

Chapter 1 Installation and Preparation

Strip 7 mm (0.28 inches) of the cable covering, and then insert the cable here.

Incorrect

Correct

The wire itself is in contact with the chassis.

Wire scraps are in contact with the chassis.

Strip gauge

7 mm (0.28 inches)

Use this screw to fix the cables cables in place so that they do not come loose.

Local sensing jumpers

Even if you turn the output off or turn the POWER switch off, if the bleeder on/off setting (CF11) is set to oFF, the voltage that was present when the output was on will remain at the output terminals. Set the bleeder on/off setting to on before you touch the sensing terminals.

Regardless of whether local sensing or remote sensing is used, be sure to attach the sensing terminal cover before turning the POWER switch on.

If the sensing cables come loose, the output voltage across the load may become unstable, and an excessive voltage may be applied to the load. If an appropriate OVP trip point is set, the OVP will trip before an excessive voltage is generated.

When you are finished with remote sensing, return to local sensing mode.

Figure 1-19. Sensing Cable Connections

Terminal Function

-S Negative remote sensing terminal.

-LS Negative local sensing terminal connected to the negative output terminal

— Not connected.

+LS Positive local sensing terminal connected to the positive output terminal.

+S Positive remote sensing terminal.

Sensing cable: AWG28 to AWG16

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Table 1-2. Sensing Terminals and Functions

RMX Programmable Power Supplies User Manual

–

+LS

-LS

-S

Output terminal

Chassis terminal

Sensing terminal

RMX

Load

Use twisted-pair wires for the load cables. Make the cables as short as possible.

Local Sensing

By factory default, RMX programmable power supplies are set to local sensing (the rear panel sensing connector is hard wired). The sensing point during local sensing is the output terminal. This method does not compensate for the voltage drop across the load cable, so use this method when the load current is small or when you do not need to consider the load effect voltage.

Figure 1-20. Local Sensing

Remote Sensing

Remote sensing is a feature that reduces the effect of voltage drops across load cabling resulting in a more accurate voltage being applied at the terminals of the load.

Refer to Appendix A, Specifications for the maximum voltage drop each RMX power supply's remote sense terminals can compensate for. Select a load cable that has sufficient current capacity to prevent the voltage drop in the load cable from exceeding the compensation voltage. Refer to the Load Cables section for more information about the cables.

When using remote sensing, the output terminals compensate for the voltage drop across the load cabling by increasing the output voltage above the programmed setpoint until the sense leads detect the programmed setpoint at the load itself. This requires the output terminals to generate a voltage that is greater than the programmed voltage level. If you are performing remote sensing with the voltage close to the maximum output voltage of the power supply, the total output is still limited by the maximum output voltage at the terminals of the power supply (105% of the rated output voltage). If the signal doesn’t seem to be stable, an electrolytic capacitor may be required at the sensing point (across the load).

To minimize noise on the output signal, use twisted-pair wires or 2-core shielded wires. Connect the ground of your shielded wire to the ground of the RMX programmable power supply or the load.

Chapter 1 Installation and Preparation

Band

Figure 1-21. Remote Sensing

RMX

Output terminal

Chassis terminal

Sensing terminal

+LS

-LS

-S

Use twisted-pair wires for the load cables. Make the cables as short as possible.

Load

–

For the sensing cables, use twisted-pair wires or shielded wires.

–

Connect an electrolytic capacitor across the load as necessary.

1. Turn the POWER switch off.

2. Remove the sensing connector from the rear panel sensing terminals.

3. Remove the local sensing jumpers from the sensing connector.

4. Remove 7 mm of the wire covering. Connect the negative sensing cable to -S and the positive sensing cable to +S.

Use cable screws to securely fix the cables in place so that they do not come loose.

5. Pinch the tip of the band, and remove the band from the connector cover.

Figure 1-22. Bottom Cover with Band

6. As shown in the figure, create a ring 40 mm away from the connector, and fasten with the band.

Make the ring as small as possible, and fasten the band as tight as possible. The band can be reused. Do not cut the extraneous portion of the band.

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RMX Programmable Power Supplies User Manual

through the hole by holding this area with a pair of tweezers.

Figure 1-23. Sensing Wire Assembly

40 mm

You can pull out the band that you passed

7. Firmly attach the sensing connector to the sensing terminals.

8. Fasten the lower side of the connector cover to the panel with the included screws, and then insert the tip of the band into the hole of the cover. Finally, bring the top and bottom sides of the connector cover together, and fasten with the included screws.

Figure 1-24. Connector Cover Assembly

9. Turn the power switch on.

Chapter 1 Installation and Preparation

Load

–

–S

–

Connecting an Electrolytic Capacitor Across the Load

If the cabling is largely inductive, it may be necessary to connect an electrolytic capacitor across the load. If you run into this problem, the following symptoms may appear:

• The output of the power supply is oscillating. If very long wires are used to connect the load, the inductive and capacitive components of the cable can cause phase shifting that results in oscillation at the output. You can reduce this effect by shortening the load cables. However, if this does not rectify the problem, connect and electrolytic capacitor across the load.

• If the load current is changing rapidly in a pulse-shaped pattern, the output voltage may fluctuate due to inductance in the cabling. You can reduce the inductance component by twisting the load cables, which stabilizes the voltage. However, if this does not rectify the problem, connect an electrolytic capacitor across the load.

Table 1-3. Electrolytic Capacitor with RMX Programmable Power Supplies

RMX-4120 RMX-4124

RMX-4121/ RMX-4125

RMX-4122/

RMX-4126

RMX-4123/ RMX-4127

36 V or more 96 V or more 276 V or more 780 V or more

Capacitance: 0.1 μF to a few hundred μF. Withstand voltage: At least 120% of the rated output voltage of the RMX programmable power supply.

Inserting a Mechanical Switch Between the RMX Programmable Power Supply and the Load

If you want to connect and disconnect the load using a mechanical switch that is inserted between the RMX programmable power supply and the load, be sure to include switches in the sensing cables as shown in the following figure. Also make sure to turn on and off the load cable and sensing cables simultaneously. Before you turn the mechanical switch on or off, be sure to turn the output or the POWER switch off.

Figure 1-25. Mechanical Switch in a Sensing Cable

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RMX Programmable Power Supplies User Manual

Accessories

RMX programmable power supplies have the following available accessories. For more information about accessories contact National Instruments.

Parallel Operation Signal Cable

This cable is used when you perform parallel operations. The following three types are available:

Part Number Description

784821-01 Cable Assembly, RMX-412x Parallel Operation (2 units)

784822-01 Cable Assembly, RMX-412x Parallel Operation (3 units)

784823-01 Cable Assembly, RMX-412x Parallel Operation (4 units)

Figure 1-26. Parallel Operation Signal Cable

Lit

Basic Functions

This chapter describes how to turn the output on and off and the basic operations that you can perform from the front panel.

Measured Value Display and Setting Display

The voltage and current displays have the following two states:

• Measured value display

• Setting display

Measured Value Display

When the SET key LED is off, the front panel will display the measured value of the voltage and current at the output terminals. You can still change the output voltage and current settings while in this state, but the front panel will continue to display the values measured at the output. Refer to the Using the RMX Programmable Power Supplies as a CV or CC Power Supply section for more information about these functions.

Figure 2-1. Measured Value Display

Power Display

While in the measured value display, press PWR DSPL to display the output power on the ammeter.

The output power is calculated from the measured output voltage and the measured output current.

When displaying the output power, the PWR DSPL key LED will light up. Press PWR DSPL again to return to measured value display.

Figure 2-2. Power Display

Chapter 2 Basic Functions

Lit

Setting Display

Press SET to display the present output voltage and output current settings, which will cause the SET key LED to illuminate. Press SET again to return to the measured value display.

Figure 2-3. Setting Display

When you recall a preset memory entry, the values stored in the preset memory entry are displayed on the panel.

Overvoltage Protection and Overcurrent Protection Setting Display

Press OCP•OVP to light its LED and display the present overcurrent protection and overvoltage protection settings.

Figure 2-4. OCP and OVP Display

System Configuration Setting Display

Press CONFIG to light its LED and display the present system configuration settings. Refer to the CONFIG Settings section for detailed information about these settings.

Figure 2-5. System Configuration Setting Display

Lit

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RMX Programmable Power Supplies User Manual

Decrease IncreaseIncrease Decrease

Panel Operations

Measured Value Display, Setting Display, and Set OVP/OCP Display

Turn the VOLTAGE knob to change the voltage. Turn the CURRENT knob to change the current.

Figure 2-6. Panel Operations

While in setting display mode (the SET key LED is illuminated), turning the VOLTAGE and CURRENT knobs will update the output voltage and current settings.

You cannot set the output voltage to a value that is 95% of the OVP trip point or higher. You cannot set the output current to a value that is 95% of the OCP trip point or higher.

The displayed current or voltage may not change when you turn the CURRENT or VOLTAGE knob. This is because the values are being changed at a finer resolution than the front panel can display. The display will update when the amount that you change the value by reaches the smallest display digit of the set voltage or current.

Fine Adjustment

Holding down the SHIFT key while turning the VOLTAGE or CURRENT knobs allows for finer adjustment of the programmed voltage and current values.

Note When you set a value, it is convenient to first use normal resolution to set the

value roughly and then switch to fine resolution to set it precisely.

Output Operations

The toggles each time you press OUTPUT. When output is on, the OUTPUT LED in the display area lights. When the output is off, the OUTPUT LED in the display area turns off.

When the OUTPUT key LED is on, the power supply will drive its output terminals to a level determined by the voltage and current settings. If you change the settings while the output is on, the changes are applied immediately to the output. If you change the settings while the output is off, the device will switch to setting display mode (the SET key LED will light up). Pressing OUTPUT will apply and drive the output terminals using the new settings.

Chapter 2 Basic Functions

Lit

You can use external control to toggle the output as well. Refer to Chapter 3, External Control, for additional information. CONFIG setting CF12 can be used to program the device to prioritize CC or CV mode at startup.

Figure 2-7. Output Operations

Output State at Power-up

In the factory default settings, the output is off when the RMX programmable power supply turns on. Using CONFIG parameter CF02, you can set the RMX programmable power supply so that output is turned on at power on.

If you set the RMX programmable power supply so that output is turned on at power on, be sure to check that the OVP trip point is set appropriately before you turn the RMX programmable power supply off.

Caution If you change the load, it may be damaged if the RMX programmable

power supply OVP and OCP settings are not correct.

Operation Overview

The RMX programmable power supply is a constant voltage (CV)/constant current (CC) regulated DC power supply that can output a wide range of voltage and current within rated output power.

If you configure the settings so that output voltage × output current is less than or equal to the rated output power, the RMX programmable power supply operates as a traditional constant-voltage (CV)/constant-current (CC) power supply.

If you configure the settings so that “output voltage × output current” is greater than the rated output power, the actual output is limited by the power limit (approximately 105% of the rated output power), and the output voltage and output current change depending on the load value.

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RMX Programmable Power Supplies User Manual

0 20 40 60 80 100 120 140 150 160

Rated output voltage: 30 V

Rated output power

Rated output current

Output voltage (V)

Output current (A)

RMX-4120: 750 W RMX-4124: 1500 W

Rated output power

01020304050 80

RMX-4120

60 70 75

RMX-4124

Output voltage (V)

Rated output voltage: 80 V

Rated output power

Rated output current

RMX-4121: 750 W RMX-4125: 1500 W

Rated output power

0 5 10 15 20 25 30

0 102030405060

RMX-4121

RMX-4125

Output current (A)

Figure 2-8. RMX-4120/4124 Output Power

Figure 2-9. RMX-4121/4125 Output Power

Chapter 2 Basic Functions

300

250

200

150

100

024681012

0 4 8 12162024

RMX-4122: 750 W RMX-4126: 1500 W

Rated output voltage: 230 V

Rated output power

Rated output current

RMX-4122

RMX-4126

Output voltage (V)

Output current (A)

700

600

500

400

300

200

100

012345 786

Rated output voltage: 650 V

Rated output power

Rated output current

Output voltage (V)

Output current (A)

RMX-4123: 750 W RMX-4127: 1500 W

Rated output power

0 0.5 1 1.5 2 2.5 3.5 43

RMX-4123

RMX-4127

Figure 2-10. RMX-4122/4126 Output Power

Figure 2-11. RMX-4123/4127 Output Power

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RMX Programmable Power Supplies User Manual

CV Power Supply and CC Power Supply

The RMX programmable power supply can operate in constant-voltage (CV) or constant-current (CC) mode. The operation mode is determined by the following three values.

• The set output voltage (VS)

• The set output current (I

• The load resistance (RL)

The operation modes are described below.

Figure 2-12. RMX Programmable Power Supplies Operation Modes

)

ma x

out

Output voltage V

Output current I

RL > R

out

SImax

RL = R

RL < R

Crossover point

A = CV mode area B

= CC mode area

= Set voltage

= Set current

= Vs/Is (Ohm’s Law)

= Load resistance

= Maximum settable voltage

max

= Maximum settable current

max

The above figure shows the operation modes of an RMX programmable power supply. The load resistance is denoted as RL. The compliance resistance RC is calculated from the set voltage and current (RC=VS/IS). The power supply is designed so that it operates in CV mode in area A and CC mode in area B. The boundary between the two operation modes is the line defined by R

RC. This line represents the load at which the output voltage equals the set voltage and the output current equals the set current. If load resistance RL is greater than the compliance resistance RC, the operating point falls in area A, and the RMX programmable power supply will operate in CV mode (point p). In this case, the set current I

operates as a current limit.

When operating in CV mode, the output voltage is maintained at the programmed voltage setpoint. The output current I is determined by the equation I = V

and is less than current

S/RL

limit IS. The actual current that flows is determined by the voltage setpoint and the load resistance and will not necessarily be equal to the programmed value.

For loads which may cause transient current spikes, current I

must be set so that the peak value

does not reach the current limit.

Conversely, if load resistance R

is less than the compliance resistance RC, the operating point

falls in area B, and the RMX programmable power supply operates in CC mode (point q). In this case, set voltage V

operates as a voltage limit.

Chapter 2 Basic Functions

When operating in CC mode, the output current is maintained at the programmed current setpoint. The output voltage V is determined by the equation V = I

× RL and is less than voltage

limit VS. The actual voltage that flows is determined by the current setpoint and the load resistance and will not necessarily be equal to the programmed value.

For loads that generate transient voltage spikes, V

must be set so that the surge voltage does not

reach the voltage limit.

Crossover Point

The RMX programmable power supply switches automatically between CV mode and CC mode according to the changes in the load. A crossover point is the point at which the mode switches.

For example, when operating in CV mode, if the load changes and the output current reaches the current limit, the RMX programmable power supply automatically switches to CC mode to protect the load. Likewise, when operating in CC mode, if the output voltage reaches the voltage limit, the RMX programmable power supply switches to CV mode.

CV Mode and CC Mode Operation Examples

This section uses a power supply with a rated output voltage of 100 V and a rated output current of 10 A as an example.

Example 1

A load resistance (RL) of 8 Ω is connected to the output terminals of the power supply. The output voltage and output current are set to 30 V and 5 A, respectively. In this case,

= 30 V/5 A = 6 Ω. Because 8 Ω is greater than 6 Ω (RL > RC), the power supply operates in

CV mode. When you want to increase the voltage in CV mode, you can increase the voltage up to the voltage defined by the following equation: Vs = Is × R Vs = 5 A × 8 Ω = 40 V. If you try to increase the voltage above this point, the crossover point is reached, and the power supply automatically switches to CC mode. To maintain operations in CV mode, increase the current limit.

. Substituting the values, obtains

Example 2

Next, a load resistance (RL) of 5 Ω is connected to the output terminals of the power supply. The output voltage and output current are set to 30 V and 5 A, respectively. In this case,

= 30 V/5 A = 6 Ω. Because 5 Ω is less than 6 Ω (RL < RC), the power supply operates in

CC mode. When you want to increase the current in CC mode, you can increase the current up to the current defined by the following equation: I IS = 30 V/5 Ω = 6 A. If you try to increase the current above this point, the crossover point is reached, and the power supply automatically switches to CV mode. To maintain operations in CC mode, increase the voltage limit.

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= VS/RL. Substituting the values, obtains

RMX Programmable Power Supplies User Manual

Using the RMX Programmable Power Supplies as a CV or CC Power Supply

When using the RMX programmable power supply as a constant-voltage power supply, the set current is the limit to the current that can flow through the load.

When using a RMX programmable power supply as a constant-current power supply, the set voltage is the limit to the voltage that can be applied to the load.

If the specified limit is reached, the RMX programmable power supply automatically switches its operation mode. When the RMX programmable power supply switches its operation mode, the lit LED in the display area (CV LED or CC LED) changes to indicate the switch.

1. Turn the POWER switch off.

2. Connect the load to the output terminals.

3. Turn the POWER switch on. If the OUTPUT LED in the display area is lit, press OUTPUT to turn the output off.

4. Press SET to change to the setting display. The SET key lights.

5. Turn the VOLTAGE knob to set the voltage.

Voltage Range: 0 to 105% of the Rated Output Voltage

RMX-4120 0 to 31.5 V

RMX-4121 0 to 84 V

RMX-4122 0 to 241.5 V

RMX-4123 0 to 682.5 V

RMX-4124 0 to 31.5 V

RMX-4125 0 to 84 V

RMX-4126 0 to 241.5 V

RMX-4127 0 to 682.5 V

Chapter 2 Basic Functions

6. Turn the CURRENT knob to set the current.

Current Range: 0 to 105% of the Rated Output Voltage

RMX-4120 0 to 78.75 A

RMX-4121 0 to 29.4 A

RMX-4122 0 to 10.5 A

RMX-4123 0 to 3.675 A

RMX-4124 0 to 157.5 A

RMX-4125 0 to 58.8 A

RMX-4126 0 to 21 A

RMX-4127 0 to 7.35 A

7. Press OUTPUT to turn output on.

The SET LED turns off, and the OUTPUT LED in the display area lights. The voltage and current are generated from the output terminals. When the device is operating as a constant-voltage power supply, the CV LED in the display area lights. When the device is operating as a constant-current power supply, the CC LED lights.

Even when the output is on, you can set the voltage and current by carrying out steps 5 and 6. Note that the front panel display will continue to display the actual measured voltage or current values rather than the programmed setpoints that you are adjusting. You can also adjust the voltage and current setpoints while displaying the output power by using the PWR DSPL key.

You can use CONFIG setting CF12 to tell the device to prioritize CV or CC mode when powering on the output. Set this according to the operation mode that you are using. You can prevent overshoot from occurring when the output is turned on by prioritizing CV when using the RMX programmable power supply as a constant-voltage power supply and by prioritizing CC when using the RMX programmable power supply as a constant-current power supply.

When used as a slave device, CONFIG setting CF12 is automatically set to CC. To use the RMX programmable power supply as a standalone unit or master unit after using it as a slave unit, set the operation mode that you want to use. If you do not set the operation mode, CC will continue to be prioritized.

When the output is turned on, the power supply's internal capacitors are charged. Depending on the programmed current setpoint, the device may enter CC mode for an instant.

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RMX Programmable Power Supplies User Manual

Protection Functions and Alarms

RMX programmable power supplies are equipped with the following protection functions:

• Overvoltage protection (OVP)

• Overvoltage protection 2 (OVP2)

• Overcurrent protection (OCP)

• Undervoltage limit (UVL)

• Overheat protection (OHP)

• Overheat protection 2 (OHP2)

• Fan failure protection (FAN)

• Incorrect sensing connection protection (SENSE)

• Low AC input protection (AC-FAIL)

• Shutdown (SD)

• Power limit (POWER LIMIT)

• Communication monitoring (WATCHDOG)

Chapter 2 Basic Functions

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Alarm Occurrence and Clearing Alarms

Alarm Occurrence

When a protection function is activated, RMX programmable power supplies behave as follows.

Figure 2-13. OHP Alarm Indication with Output Off

Figure 2-14. OHP Alarm Indication with Output On

Blinking (in orange)

Lit

• The output turns off. CONFIG setting CF03 allows the user to set the error clearing method for overheat protection (OHP), fan failure protection (FAN), and low AC input protection (AD-FAIL) errors. When CF03 is set to Auto, the output will automatically turn back on when the problem that caused the alarm is fixed. When CF03 is set to Safe, the output will remain off even after the problem that caused the alarm is resolved. This parameter is the same for the OHP, FAN, and AC-FAIL alarms. You cannot set this parameter separately for each protection function.

• The ALARM LED in the front panel display area lights to indicate that an alarm has occurred. The voltmeter display indicates the cause of the alarm.

• The ALARM LED on the front panel blinks only when a POWER LIMIT alarm has occurred.

• The OUTPUT LED on the front panel blinks orange only when a protection function has been activated while the output is on.

If the RMX programmable power supply is set so that output turns on automatically after the problem that caused the alarm is fixed (CF03: Auto), the OUTPUT LED lights automatically when the problem that caused the alarm is fixed. If the RMX programmable power supply is set so that output remains off even after the problem is fixed (CF03: SAFE), the OUTPUT LED remains off even after the problem that caused the alarm is fixed.

• The alarm signal is generated from pin 14 of the J1 connector (when the OVP/ OVP2/OCP/ OHP/ OHP2/ FAN/ SEN/ AC-FAIL/ SD/ WATCHDOG has been activated).

Note When a CONFIG parameter is being displayed, only the ALARM LED turns

on; the cause of alarm is not displayed. To view the cause of the alarm, exit from the CONFIG parameter display.

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RMX Programmable Power Supplies User Manual

Clearing Alarms

To clear alarms, (press ALM CLR (SHIFT+SET); (2) set pin 5 of the J1 connector to LOW (0 to 0.5 V) or shorted; or (3) turn the RMX programmable power supply off, fix the problem that caused the alarm, and then turn the RMX programmable power supply on.

If overvoltage protection 2 (OVP2), overheat protection 2 (OHP2) or Shutdown (SD) has been activated, turn the RMX programmable power supply off, fix the problem that caused the alarm, and then turn the RMX programmable power supply on.

When the overheat protection (OHP), fan failure protection (FAN), or low AC input protection (AC-FAIL) function is activated, the output is turned off. You can use the CONFIG settings to select how the RMX programmable power supply will perform after the problem that caused the alarm is fixed. You can select to turn the output back on automatically after the problem that caused the alarm is fixed (CF03: Auto) or to leave the output off (CF03:SAFE).

If an alarm still occurs even after you have corrected all the causes of alarms, the RMX programmable power supply may be malfunctioning. Stop using it immediately, and contact National Instruments. For details about the specific conditions that cause each alarm to trigger, see the explanation of each protection function.

Alarm Signal

The alarm signal is isolated from other terminals as it is through an open collector photocoupler. Maximum voltage is 30 V and maximum current is 8 mA.

Figure 2-15. Alarm Signal

ALM STATUS

STATUS COM

J2 connector

6-9

RMX

Chapter 2 Basic Functions

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Protection Function Activation

Setting limitation functions

You can use the CONFIG settings to apply limits to the voltage and current output settings. You can set limitations so that the programmed values cannot exceed the set overvoltage protection (OVP trip point) and the set overcurrent protection (OCP trip point) and so that the values cannot be lower than the set undervoltage limit (UVL trip point).

By using this feature, you can avoid accidentally turning the output off by mistakenly setting the voltage or current to a value that exceeds the set OVP or OCP or to a value that is lower than the set UVL.

If you have selected to limit the voltage setting (CF15: on), the valid programmable voltage values will be limited to voltages that are less than 95% of the OVP trip point and voltages that are greater than the UVL trip point. In addition, you will no longer be able to set the OVP trip point to a value that is lower than the set output voltage or the UVL trip point to a value that exceeds the set output voltage.

If you have selected to limit the current setting (CF14: on), the valid programmable current values will be limited to currents that are less than 95% of the OCP trip point. In addition, you will no longer be able to set the OCP trip point to a value that is lower than the set output current.

Overvoltage Protection (OVP), Overvoltage Protection 2 (OVP2), and Overcurrent Protection (OCP)

The overvoltage protection (OVP) function is activated under the following conditions.

• When the output terminal voltage exceeds the set OVP trip point.

• When the load or the RMX programmable power supply is malfunctioning.

The overvoltage protection 2 (OVP2) function is activated under the following conditions.

• When the output terminal voltage exceeds 120% of the rated output voltage (when a voltage is being applied from an external source).

• When the load or the RMX programmable power supply is malfunctioning.

If OVP2 is activated, turn the POWER switch off and on.

Figure 2-16. Alarm When OVP2 has been Activated

The overcurrent protection function (OCP) is activated under the following conditions.

• When the output current exceeds the set OCP trip point.

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RMX Programmable Power Supplies User Manual

• When the load or the RMX programmable power supply is malfunctioning.

Set the OVP and OCP trip points to appropriate values. Immediately after you purchase the RMX programmable power supply or immediately after a load is changed, you have to set the OVP and OCP trip points to values that are appropriate for the load.

The OVP2 trip point is fixed to 120% of the rated output voltage.

RMX-4120/

RMX-4124

RMX-4121/

RMX-4125

RMX-4122/ RMX-4126

RMX-4123/

RMX-4127

OVP2 Trip Point 36 V 96 V 276 V 780 V

Setting the OVP and OCP Trip Points and the Detection Time of OCP Activation

OVP will trigger based on the voltage at the output terminals of the power supply. If you want to activate the protection function according to the voltage across the load, take the voltage drop in the load cable into consideration when you set the OVP trip point.

You can use the CONFIG settings to set the detection time of the OCP activation (CF13)

Figure 2-17. OVP and OCP Trip Point Displays

OCP trip point

1. Press OCP•OVP.

The OCP•OVP key LED lights up, and the OVP trip point and OCP trip point are displayed in the display area.

2. While viewing the panel display, turn the VOLTAGE knob to set the OVP trip point or the CURRENT knob to set the OCP trip point.

OVP setting range: 10% to 112% of the rated output voltage

OCP setting range: 10% to 112% of the rated output current

OVP trip point

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OVP Setting

OCP Setting 750 W

OCP Setting 1500 W

RMX-4120/

RMX-4124

3 to 33.6 V 8 to 89.6 V 23 to 257.6 V 65 to 728 V

7.5 to 84 A 2.8 to 31.36 A 1 to 11.2 A 0.35 to 3.92 A

15 to 168 A 5.6 to 62.72 A 2 to 22.4 A 0.7 to 7.84 A

RMX-4121/

RMX-4125

3. Press OCP•OVP twice to finalize the settings.

RMX-4122/

RMX-4126

RMX-4123/

RMX-4127

Chapter 2 Basic Functions

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Blinking (in orange)

The OCP•OVP key LED turns off, and the RMX programmable power supply returns to the measured value display.

Checking OVP and OCP Operation

The OVP and OCP functions are designed to protect the load.

If you use the CONFIG settings to limit the voltage setting (CF15: ON), you will no longer be able to set the output voltage to a value that exceeds the OVP trip point. This means that you won’t be able to check the operation of the OVP function. If you use the CONFIG settings to limit the current setting (CF14: ON), you will no longer be able to set the output current to a value that exceeds the OCP trip point. This means that you won’t be able to check the operation of the OCP function.

Complete the following steps to check the operation of the OVP function. Ensure CF15 is set to OFF.

1. Check that the OUTPUT LED in the display area is turned off.

2. Set the output voltage to a value lower than the OVP trip point.

3. Press OUTPUT to turn output on. The OUTPUT LED lights.

4. Slowly turn the VOLTAGE knob clockwise.

When the output voltage exceeds the OVP trip point, the front panel display area’s ALARM LED lights and the OUTPUT LED blinks to indicate that the OVP function has been activated.

Figure 2-18. Display of the OVP Activation Alarm

5. Check that output has turned off.

6. Turn the POWER switch off.

Complete the following steps to check the operation of the OCP function. Ensure CF14 is set to OFF.

1. Short the output terminal.

2. Turn the POWER switch on.

3. Check that the OUTPUT LED in the display area is turned off.

4. Set the output current to a value lower than the OCP trip point.

5. Press OUTPUT to turn output on. The OUTPUT LED lights.

6. Slowly turn the CURRENT knob clockwise.

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When the output current exceeds the OCP trip point, the front panel display area’s ALARM LED lights, and the OUTPUT LED blinks to indicate that the OCP function has been activated.

RMX Programmable Power Supplies User Manual

Lit

Blinking (in orange)

Figure 2-19. Display of the OCP Activation Alarm

7. Check the output has turned off.

If you do not change the output settings, the OVP or OCP function will be activated again.

Undervoltage Limit (UVL)

This protection function is activated when you attempt to set the output voltage to a value that is lower than the set undervoltage limit (the UVL trip point). In other words, it prevents you from setting the output voltage to a value lower than the set limit. Triggering this protection function does not turn the output off.

CONFIG setting CF15 allows you to choose whether the output setpoint is limited so that it cannot be set to a value lower than the UVL trip point.

Complete the following steps to set the UVL trip point.

1. Press OCP•OVP.

The OCP•OVP key lights, and the OVP trip point and OCP trip point are displayed in the display area.

2. Press OCP•OVP again. The present UVL trip point is displayed.

Figure 2-20. Display Example of the UVL Setting

3. While viewing the panel display, turn the VOLTAGE knob to set the UVL trip point.

UVL Setting 0 to 31.5 V 0 to 84 V 0 to 241.5 V 0 to 682.5 V

4. Press OCP•OVP to finalize setting.

Table 2-1. UVL Setting Range 0 to 105% of the Rated Output Voltage

RMX-4120/

RMX-4124

RMX-4121/

RMX-4125

RMX-4122/

RMX-4126

RMX-4123/

RMX-4127

Chapter 2 Basic Functions

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Overheat Protection (OHP), Overheat Protection2 (OHP2)

This protection function is activated when the RMX programmable power supply internal temperature rises to an abnormal level. Abnormal temperature levels can occur under the following conditions:

• When used in an environment outside its operating ambient temperature range 0°C (32°F) to 50°C (122 °F)

• When used with its air inlet and exhaust port blocked.

• When the fan motor has stopped.

Figure 2-21. Alarm Indication when OHP2 has been Activated

If OHP2 is activated, turn the POWER switch off and on.

If you do not fix the problem that caused the OHP or OHP2 to be activated, OHP or OHP2 will be activated again even if you restart the RMX programmable power supply.

Fan Failure Protection (FAN)

This function is activated when the number of fan rotations drops to an abnormal level.

Figure 2-22. Alarm Indication when FAN has been Activated

Incorrect Sensing Connection Protection (SENSE)

This function is activated when the remote sensing cables are connected with the incorrect polarity (positive or negative), and the remote sensing function is then used.

Figure 2-23. Alarm Indication when SENSE has been Activated

Low AC Input Protection (AC-FAIL)

This function is activated when a low AC input is detected.

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Figure 2-24. Alarm Indication when (AC-FAIL) has been Activated

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Shutdown (SD)

Shutdown (SD) is not activated as a result of the RMX programmable power supply detecting an error. It is a function that is used to turn the output off through the application of a signal to pin 6 of the rear-panel J1 connector when an abnormal condition occurs.

If SD is activated, turn the POWER switch off and on.

Figure 2-25. Alarm Indication when SD has been Activated

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Power Limit (Power Limit)

This function changes the output voltage or output current according to the changes in the load resistance. This function limits the output power to a value that is approximately 105% of the rated output power. This function does not turn the output off.

When the power limit function has been activated, the ALARM LED blinks. An alarm signal is not transmitted.

Table 2-2. Power Limits

750 W Model 1500 W Model

787.5 W 1575.0 W

Communication Monitoring (WATCHDOG)

The watchdog function monitors the SCPI command communication status. Communication is assumed to have stopped if there is no communication within the time period specified by the communication monitoring timer setting (CF17).

This function operates regardless of whether the product is in remote or local (panel control) mode. When using local mode (panel control), set communication monitoring to off in the timer settings. When using remote mode, you can set the timer using a command (OUTP:PROT:WDOG).

Chapter 2 Basic Functions

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Parameter number, CF (CONFIG) + a two-digit number

Setting display

Lit

You cannot stop communication monitoring with the *RST, *RCL, or *CLS command. In the alarm state, turn off communication monitoring before clearing the alarm.

Figure 2-26. Alarm Indication when WATCHDOG has been Activated

CONFIG Settings

Use the CONFIG settings to set the RMX programmable power supply’s system configuration. You can set and display the following parameters in the CONFIG settings.

Effect column † indicates a parameter that may be affected when the panel

settings are reset (CF00), or when a preset memory entry is loaded.

* indicates a parameter that may be affected when the master unit, the slave unit, or the number of units is changed (CF01).

‡ indicates a parameter that may be affected when the LAN interface settings are reset (CF40:LCi/dEF).

Note column A indicates a parameter that is applied immediately.

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B indicates a parameter that is applied when the RMX programmable power supply is turned on.

C indicates a parameter that is applied when CF40 “APPL” is executed.

Figure 2-27. CONFIG Setting and Display Examples

RMX Programmable Power Supplies User Manual

Table 2-3. CONFIG Settings

Display

Switching

Parameter

Number Description Effect Note

SYSTEM CF00

CF01 Master-slave parallel operation parameter * B

CF02

CF03 Method for clearing OHP, FAN, and AC-FAIL

CF04

CF05

CF06

CF07

CF08 Range during voltage and current monitoring — A

CF09

CF10

CF11 Bleeder on/off parameter — A

CF12

CF13 Detection time of OCP activation — A

CF14

CF15

Resets the panel settings — A

Power-on status parameter — B

alarms

Memory content display parameter — A

CC control using an Vext or Rext † A

CV control using an Vext or Rext † A

CV/CC control range parameter — A

External control parameter for turning output on and off † * A

External control logic parameter for turning output on and off

Output-on startup state parameter * A

Current setting limit † * A

Voltage setting limit † * A

— B

* A

CF16 Panel display brightness setting — A

CF17 Communication monitor timer setting — A

CF18 Unused — —

CF19

Current and power display on slave units for

— A

master-slave parallel operation

Chapter 2 Basic Functions

Table 2-3. CONFIG Settings (Continued)

Display

Switching

Interface

LAN

Parameter

Number Description Effect Note

CF20 LAN interface parameter * ‡

CF21 Command language parameter * B

CF22 Emulation parameter during remote control * B

CF23 SCPI communication error display parameter * A

CF24 Multichannel (VMCB) domain number parameter * ‡

CF25 Multichannel (VMCB) channel number * ‡

B or C

CF30 IP address display (1) * —

CF31 IP address display (2) * —

CF32 IP address display (3) * —

CF33 IP address display (4) * —

CF34 MAC address display (1) and (2) * —

CF35 MAC address display (3) and (4) * —

CF36 MAC address display (5) and (6) * —

CF40 Resets (LCI/DEF) or applies (APPL) the LAN settings. * A

CF41 IP address assignment method * ‡ B or C

CF42 Manual IP address setting (1) * ‡ B or C

CF43 Manual IP address setting (2) * ‡ B or C

CF44 Manual IP address setting (3) * ‡ B or C

CF45 Manual IP address setting (4) * ‡ B or C

CF46 IP address subnet mask prefix setting * ‡ B or C

CF47 SCPI-RAW protocol TCP port number * ‡ B or C

USB CF50 VID (vendor ID) display * —

CF51 PID (product ID) display * —

RS232C CF52 RS232C baud rate parameter * B

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

You can only specify this parameter only when the RMX programmable power supp ly is being used as a slave unit.

This parameter is affected only when the LAN interface settings are reset (CF40: dEF).

This parameter is displayed only when the LAN interface is in use (CF20: on).

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CONFIG key

Displayed only when the RMX series is being used as a slave unit

CONFIG key

Displayed only when the LAN interface is in use

CF00 CF01

CF19*

CF20 CF21

CF25

VOLTAGE knob Used to select the value or the parameter to display.

CONFIG key Used to select the parameter number.

CURRENT knob Used to select the parameter number.

Measured value display

System settings

Interface settings

. . .

LAN settings (Display)

LAN settings (Parameter)

．．．

CF30 CF31

CF36

．．．

CF40 CF41

CF47

CURRENT knob

USB/RS232C settings

CF50 CF51 CF52

CURRENT knob

RMX Programmable Power Supplies User Manual

Figure 2-28. Selecting CONFIG Parameters

Note CF00, and CF40 are used to execute operations. CF30 to CF36, CF50,

and CF51 are read-only parameters used to display the status of the RMX programmable power supply. You cannot set the values of any of these CONFIG parameters.

Note The SET key blinks when you have selected a CONFIG parameter whose

setting you must confirm by pressing SET (CF00, and CF40).

Chapter 2 Basic Functions

Specifying CF01 to CF36, CF 41 to CF52 CONFIG Settings

Note Excludes CF00 (Reset panel settings) and CF40 (Resets or applies LAN

interface settings).

Complete the following steps to specify the CONFIG settings.

1. Press CONFIG.

The CONFIG key lights, and the SET key blinks. The ammeter displays the parameter number—CF00. The voltmeter displays the corresponding setting—rSt.

2. Press CONFIG or turn the CURRENT knob to select the number of the parameter that you want to set.

When you press CONFIG, the RMX programmable power supply switches between the parameter ranges in the following order.

CF00 -->CF20 -->CF30 -->CF40 -->CF50 -->measured value display

When you turn the CURRENT knob, the RMX programmable power supply increments through the parameter numbers within the currently selected parameter range.

Tip Press CONFIG or turn the CURRENT knob to switch between the parameter

numbers. These two methods switch between the parameter numbers differently.

3. Turn the VOLTAGE knob to change the value of the parameter.

4. To specify or display other parameters, repeat steps 2 and 3. To stop specifying CONFIG settings, proceed to step 5.

5. Continue pressing CONFIG until the measured value display appears. Alternatively, press OUTPUT or PWR DSPL. If you are configuring a slave unit, press CONFIG or PWR DSPL.

Some CONFIG parameters will be applied immediately after you set them, some will be applied after you restart the RMX programmable power supply, and some will be applied after you execute CF40 “APPL”.

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Specifying CF00/CF40 CONFIG Settings

• Resetting the panel settings (CF00)

• Resetting or applying the LAN interface settings (CF40)

Complete the following steps to specify the CONFIG settings for CF00 or CF40

1. Press CONFIG once (for CF00) or four times (for CF40).

The CONFIG key lights and the SET key blinks.

If you pressed CONFIG once, the ammeter displays the parameter number—CF00. The voltmeter displays the corresponding setting—rSt. If you pressed CONFIG four times, the ammeter displays the parameter number—CF40. The voltmeter displays the corresponding setting—Lci/dEF/APPL.

2. Press SET, which is blinking.

The CONFIG key lights, and the SET key, the parameter number displayed on the ammeter, and the setting displayed on the voltmeter all blink.

3. Press SET, which is blinking, again.

While the parameter number and the setting are blinking, no new settings will be applied until you press SET.

When setting CF00, the measured value display appears.

When CF40 is set, the LAN LED lights in orange (for about 4 to 5 seconds) while the setting is being confirmed and then turns green when it is complete. Press SET to exit the CONFIG settings. The settings will be applied.

If the LAN LED turns red, set the settings again.

CONFIG Parameter Details

The CONFIG parameters are explained in detail below.

CF00 Resets the Panel Settings

This configuration parameter resets all of the settings listed below to their default values. The following settings will be reset. When the settings are reset, the RMX programmable power supply settings take on the same values as they do when an *RST command is received.

You can only use this parameter when the RMX programmable power supply is being used as a master unit.

• Output voltage

• Output current

• Overvoltage protection

• Overcurrent protection

• Undervoltage limit

• Output on/off at power-on

• Constant current control using an Vext or Rext (CF05)

Chapter 2 Basic Functions

• Constant voltage control using an Vext or Rext (CF06)

• External control setting for turning output on and off (CF09)

• Voltage and current setting limits (CF15 and CF14)

Value Parameter Description

rSt Resets the panel settings

CF01 Master-slave Parallel Operation Parameter

Sets the total number of units (master unit and slave units) in master-slave parallel operation. Specify “SLAV” for the units that you want to use as slaves. This parameter is applied when you turn the POWER switch off and on.

Changing this setting may affect the settings of the master unit or the slave units that are connected in parallel.

Value Parameter Description

SLAV Use the RMX as a slave unit

1 to 4 Set the total number of units (1 to 4; 1 indicates independent

operation–factory default setting).

CF02 Power-on Status Parameter

Sets the condition that the RMX programmable power supply will be in when the power is turned on. This setting is invalid when you are using an external contact to turn the output off. This parameter only applies when you turn the POWER switch off and on.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

SAFE The settings that were in use immediately before the POWER

switch was turned off are used. The output is off (factory default setting).

Auto The settings that were in use immediately before the POWER

switch was turned off are used. This includes whether output was on or off.

ForC The settings that were in use immediately before the POWER

switch was turned off are used. The output is turned on.

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CF03 Method for Clearing OHP, FAN, and AC-FAIL Alarms

Sets the method for clearing alarms when overheat protection (OHP), fan failure protection (FAN), or low AC input protection (AC-FAIL) has been activated. You cannot set this parameter separately for each protection function.

When you select “Auto,” if the overheat protection function (OHP) has been activated, output will turn on again automatically when the internal temperature drops to a normal level. However, if you do not fix the problem that caused the alarm to occur, the alarm will occur again, which will force you to clear the alarm again. The overheat protection devices have long service lives (approximately 100000 uses), but if they reach the end of their service lives, they will stop operating. To maintain the performance of the RMX programmable power supply for a long time, we request that you fully understand the Auto feature and only use it when necessary.

Value Parameter Description

SAFE After the problem that caused an alarm to occur is fixed, the

output is not turned on automatically (factory default setting).

Auto After the problem that caused an alarm to occur is fixed, the

output is turned on automatically.

CF04 Memory Content Display Parameter

Sets whether to display the saved contents in the preset memory before recalling them. You can use this CONFIG parameter if you forget what settings have been saved to a preset memory entry or if you want to view the saved settings.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

oFF The saved contents of preset memory will be recalled without

displaying them.

on The saved contents of preset memory will be displayed and then

recalled after confirmation (factory default setting).

CF05 CC Control Using a Vext or Rext

Selects whether constant current will be controlled by an external voltage (Vext) or an external resistance (Rext) or an external resistance (Rext) via the J1 connector. This is set to “oFF” when the panel settings are reset (CF00) and when a preset memory entry is recalled.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Chapter 2 Basic Functions

Value Parameter Description

oFF External control will not be performed (factory default setting).

on External control will be performed.

CF06 CV Control Using a Vext or Rext

Selects whether constant voltage will be controlled by an external voltage (Vext) or an external resistance (Rext) via the J1 connector. This is set to “oFF” when the panel settings are reset (CF00) and when a preset memory entry is recalled.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

oFF External control will not be performed (factory default setting).

on External control will be performed.

CF07 CV/CC Control Range Parameter

Selects the range that is used when controlling constant current and constant voltage with an external voltage or an external resistance (the J1 connector).

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

Lo 0 to 5 V (factory default setting)

hi 0 to 10 V

CF08 Range During Voltage and Current Monitoring

Selects the range during voltage and current monitoring.

Value Parameter Description

Lo 0 to 5 V (factory default setting)

hi 0 to 10 V

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RMX Programmable Power Supplies User Manual

CF09 External Control Parameter for Turning Output On and Off

Selects whether an external contact (pin 18 on the J1 connector) will be used to turn output on and off. This is set to “oFF” when the panel settings are reset (CF00) and when a preset memory entry is recalled.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

oFF External control is not performed (factory default setting).

on External control is performed.

CF10 External Control Logic Level for Turning Output On and Off

Sets the logic level used when an external contact (pin 18 on the J1 connector) is being used to turn output on and off.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

Lo Output is turned on when a LOW signal (0 to 0.5 V) or

short-circuit is received (factory default setting).

hi Output is turned on when a HIGH signal (4.5 to 5 V) or

open-circuit is received.

CF11 Bleeder On or Off

Turns the bleeder circuit on and off. You can turn the bleeder circuit off when you don’t want the electric charge stored in the output capacitance of the supply to sink into the internal bleeder circuit, such as when you are charging a battery.

Even when the output terminal is off (open) or when the set voltage is 0 V, if you turn the bleeder off, a voltage as large as a few hundred millivolts may appear at the output terminal.

Depending on whether the bleeder circuit is enabled, the fall time of the output voltage and the amount of current sunk into the power supply will vary when an external load is connected.

When using master-slave parallel operation or series operation, use the same settings on all connected units.

Chapter 2 Basic Functions

Value Parameter Description

oFF The bleeder circuit is turned off.

on The bleeder circuit is turned on (factory default setting).

CF12 Output-on Startup State Parameter

Sets the operation mode to be prioritized when the output is turned on. Prioritizing the operation mode appropriately can prevent unwanted output overshoots at power-up. When used as a slave device, CC is automatically prioritized. To use the RMX programmable power supply as a standalone unit or master unit after using it as a slave unit, set the operation mode that you want to use. If you do not set the operation mode, CC will continue to be prioritized.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

CC CC (constant current) is prioritized.

CV CV (constant voltage) is prioritized (factory default setting).

CF13 Detection Time of OCP Activation

Set the time when the overcurrent protection (OCP) is activated after an overcurrent is detected. Set this in 100 ms steps.

Value Parameter Description

0 0 ms (factory default setting).

100 to 2000 100 to 2000 ms

CF14 Current Setting Limit

Set whether to limit the set output current so that its value cannot exceed the set overcurrent protection (approximately 95% of the OCP trip point). When this parameter is set to "oFF" and you set it to "on" when the OCP is lower than the current setpoint, the value of the current setpoint is maintained and the OCP value will automatically be increased to be 105% of the current setpoint. The parameter will also be changed if the output is on.

This is set to “on” when the panel settings are reset (CF00) and when a preset memory entry is recalled.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

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RMX Programmable Power Supplies User Manual

Value Parameter Description

oFF The setting is not limited.

on The setting is limited (factory default setting).

CF15 Voltage Setting Limit

Set whether to limit the set output voltage so that its value cannot exceed the set overvoltage protection (approximately 95% of the OVP trip point) and cannot be set lower than the set undervoltage limit. When this parameter is set to "oFF" and you set it to "on" when the OVP is lower than the voltage setpoint, the value of the voltage setpoint is maintained and the OVP value will automatically be increased to be 105% of the voltage setpoint. In addition, the set UVL will be changed to match the voltage setpoint. The parameter will also be changed if the output is on.

This is set to “on” when the panel settings are reset (CF00) and when a preset memory entry is recalled.

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

Value Parameter Description

oFF The setting is not limited.

on The setting is limited (factory default setting).

CF16 Panel Display Brightness Setting

Adjusts the panel display brightness. The larger the number, the brighter the display. Even if you specify the same number, the brightness may differ between individual products.

The brightness is not proportional to the setting.

Value Parameter Description

1 to 7 Screen brightness (factory default setting: 7).

CF17 Communication Monitor Timer Setting

Sets the interval for monitoring SCPI command communication. The communication monitoring function operates regardless of whether the product is in remote or local (panel control) mode. If this parameter is not set to "oFF" and the specified time expires before any the device receives any SCPI commands, the Communication Monitoring (WATCHDOG) alarm will trigger.

When using local mode (panel control), be sure to specify oFF.

Chapter 2 Basic Functions

Value Parameter Description

oFF Communication monitor timer is set to off (factory default setting).

1 to 3000 1 s, 3 s, 10s, 30s, 100s, 300s, 1000s, 3000s

CF18 Unused

Value Parameter Description

— Unused

CF19 Current and Power Display on Slave Units for Master-slave Parallel Operation

Sets whether the current or power on slave units is displayed during master-slave parallel operation. You can display and specify this parameter only when the RMX programmable power supply is being used as a slave unit.

If this parameter is set so that the current or power on slave units is not displayed, the ammeter displays”----.”

Value Parameter Description

oFF The current or power of slave units is not displayed (factory

default setting).

on The current or power of slave units is displayed.

CF20 LAN Interface Parameter

Sets whether the LAN interface will be used. By setting it to “oFF,” you can disable the LAN interface function even when a LAN cable is connected. You cannot set the LAN CONFIG settings while this parameter is turned off.

Even when this is set to “on,” if the command language is set to legacy (CF21: LGCy), you cannot use the LAN interface.

This parameter is applied when you turn the POWER switch off and on.

Value Parameter Description

oFF The LAN interface will not be used.

on The LAN interface will be used (factory default setting).

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RMX Programmable Power Supplies User Manual

CF21 Command Language Parameter

Selects the command language that is used in remote control messages. For the LAN interface to function, this parameter must be set to "SCPi."

This parameter is applied when you turn the POWER switch off and on.

Value Parameter Description

SCPi The SCPi language will be used (factory default setting).

LGCy Legacy languages will be used.

CF22 Emulation Parameter During Remote Control

Selects the emulation that is used during remote control. If you have set the command language to legacy languages, you can only select “GEn” or “PAG.”

This parameter is applied when you turn the POWER switch off and on.

Value Parameter Description

nonE Remote control is performed using the RMX programmable

power supply’s commands made by National Instruments (factory default setting).

5700 Remote control is performed using the N5700/N8700 commands

made by Agilent Technologies.

GEn Remote control is performed using the Genesys series commands

made by TDKLambda.

PAG Remote control is performed using the PAG series commands

made by Kikusui.

dCS Remote control is performed using the DCS series commands

made by Sorensen.

CF23 SCPI Communication Error Display Parameter

Selects whether to display communication errors. The errors are only displayed when you are using the SCPI language.

Value Parameter Description

oFF SCPI communication errors are not displayed (factory default

setting).

on SCPI communication errors are displayed.

Chapter 2 Basic Functions

CF24 Multichannel (VMCB) Domain Number Parameter

Set the multichannel domain number. RMX models that have the same domain number perform multichannel operations. If you do not want to use the multichannel function, set this to 0 (this is the factory default setting).

If 5700 or DCS emulation is selected, you cannot use multichannel. This parameter is applied when you turn the POWER switch off and on or when you execute CF34.

Value Parameter Description

0 The multichannel function is not used (factory default setting).

1 to 254 The domain number when the multichannel function is used.

CF25 Multichannel (VMCB) Channel Number

Set the multichannel channel number. Specify a unique number on the network. If you do not want to use the multichannel function, set this to 0 (this is the factory default setting).

If 5700 or DCS emulation is selected, you cannot use multichannel. This parameter is applied when you turn the POWER switch off and on or when you execute CF34.

Value Parameter Description

0 The RMX is used as a master unit on the multichannel network

(factory default setting).

1 to 30 1 to 30 The RMX is used as a slave unit with this channel number

on the multichannel network.

CF30 to CF33 IP Address Display

These parameters display the set IP addresses. These parameters are only displayed when you are using the LAN interface.

To set a fixed IP address use CONFIG parameters CF42 to CF45 and then apply the LAN settings with CF40. You can also set a fixed IP address when you access the power supply through a web browser. When you access the power supply through a web browser, do so under conditions in which a DHCP server or AUTO IP can be used.

Parameter Number Display Description

CF30 0 to 255 Displays the first IP address number

CF31 0 to 255 Displays the second IP address number

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RMX Programmable Power Supplies User Manual

Parameter Number Display Description

CF32 0 to 255 Displays the third IP address number

CF33 0 to 255 Displays the fourth IP address number

CF34 to CF36 MAC Address Display

These parameters display the set MAC address. The MAC address is just displayed; it cannot be set from the panel. To set a fixed MAC address, access the RMX programmable power supply through a Web browser. When you access the RMX programmable power supply through a Web browser, do so under conditions in which a DHCP server or AUTO IP can be used. By default, the MAC address is set to

00.80.2F.11.xx.xx (where x is a hexadecimal number between

0 and F).

Parameter

Number

Display Description

CF34 00.80 Displays the first and second MAC address numbers (read only).

CF35 2F.11 Displays the third and fourth MAC address numbers (read only).

CF36 xx.xx Displays the fifth and sixth MAC address numbers (read only).

CF40 Resetting (LCI/DEF) or applying (APPL) the LAN Interface Settings

Sets whether to reset or apply the LAN interface settings. This parameter is displayed and can be set only when the LAN interface is in use.

Value Parameter Description

LCI The LAN interface settings will be reset to their factory default settings.

dEF Resets the LAN interface and network settings (factory default values).

APPL Applies the CONFIG settings related to the LAN interface.

CF41 IP Address Assignment Method

Sets the IP address assignment method. This parameter is displayed and can be set only when the LAN interface is in use.

Set whether to use (on: 1) or not use (off: 0) the following: DHCP server, AUTO IP function (automatic assignment), and MANUAL IP assignment.

If an IP address is not assigned through a DHCP server, AUTO IP is used.

To use the MANUAL IP function, set the DHCP server and AUTO IP function to off. The address that is assigned by the AUTO IP function is between 0 and 254).

169.254.x.x (where x is a number

Chapter 2 Basic Functions

This parameter is applied when you turn the POWER switch off and on or when you execute APPL with CF40.

If the LAN interface settings are reset (CF40: LCi/dEF) this is set to (110).

Value/Display Parameter Description

_ _¯ DHCP:OFF, AUTO IP: OFF, MANUAL IP: ON

_¯_ DHCP:OFF, AUTO IP: ON, MANUAL IP: OFF

_¯ ¯ DHCP:OFF, AUTO IP: ON, MANUAL IP: ON

¯_ _ DHCP:ON, AUTO IP: OFF, MANUAL IP: OFF

¯_¯ DHCP:ON, AUTO IP: OFF, MANUAL IP: ON

¯ ¯_ DHCP:ON, AUTO IP: ON, MANUAL IP: OFF

(factory default setting)

¯ ¯ ¯ DHCP:ON, AUTO IP: ON, MANUAL IP: ON

CF42 to CF45 Manual IP Address Setting (Manual IP Function)

If you do not want to or cannot use a DHCP server or if you do not want to or cannot use the AUTO IP function, set the IP address manually. This parameter is displayed and can be set only when the LAN interface is in use.

These parameters are applied when you turn the POWER switch off and on when you execute APPL with CF40.

Parameter Number Value Description

CF42 0 to 255 Sets the first IP address number.

CF43 0 to 255 Sets the second IP address number.

CF44 0 to 255 Sets the third IP address number.

CF45 0 to 255 Sets the fourth IP address number.

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RMX Programmable Power Supplies User Manual

CF46 IP Address Subnet Mask Prefix Setting

If you want to set the IP address manually (MANUAL IP function), set the subnet mask prefix. This parameter is displayed and can be set only when the LAN interface is in use.

This parameter is applied when you turn the POWER switch off and on or when you execute APPL with CF40.

Parameter Number Value Description

CF46 16 to 31 Sets the subnet mask prefix.

Examples: Display example when “16” is set 255.255.0.0

Display example when “24” is set 255.255.255.0

Display example when “31” is set 255.255.255.254

CF47 SCPI-RAW Protocol TCP Port Number Setting

Set the TCP port number of the SCPI-RAW protocol for when the LAN interface is in use.

This parameter is applied when you turn the POWER switch off and on or when you execute CF40. TCP port number 4880 cannot be used.

Value Parameter Description

4000 to 9999

(except 4880, 5024, and 5044)

TCP port number (factory default setting: 5025)

Chapter 2 Basic Functions

CF50 Vendor ID Display

Displays the USB Vendor ID.

Display Description

3923 0x3923

CF51 Product ID Display

Displays the USB Product ID.

Display Description

78A3 RMX4121 0x78A3

78A4 RMX4122 0x78A4

78A6 RMX4124 0x78A6

78A7 RMX4125 0x78A7

78A8 RMX4126 0x78A8

78A9 RMX4127 0x78A9

CF52 RS232C Baud Rate Setting

Sets the RS232C baud rate. This parameter is applied when you restart the RMX programmable power supply.

Value Parameter Description

19.2 19200 bps (factory default setting)

38.4 38400 bps

57.6 57600 bps

115.2 115200 bps

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1.2 1200 bps

2.4 2400 bps

4.8 4800 bps

9.6 9600 bps

RMX Programmable Power Supplies User Manual

Preset Memory Function

RMX programmable power supplies have a preset memory function that allow users to store three sets of the following settings: voltage setpoint, current setpoint, and OVP/OCP/UVL trip points. These settings can be recalled from the preset memory slots whenever they are needed.

To save the current settings into a preset memory slot, hold down the shift key and the key for the slot you'd like to save the settings to (A, B, or C) until the key's LED illuminates.

To recall a set of saved settings, hold the shift key and press the key for the slot you'd like to recall (A, B, or C). The settings will go into effect the moment you press the memory slot key.

The recalling will be effective at the moment when you select the preset memory. To save the present settings, you need to keep holding down the keys (SHIFT+A, B, or C).

Saving Settings to Preset Memory

1. Press SET.

The SET key will light up, and the present voltage and current settings will be displayed on the panel.

2. While viewing the values displayed on the panel, use the VOLTAGE and CURRENT knobs to program the setpoint values you'd like to write to memory.

3. Press OCP•OVP

The OCP•OVP key will light up, and the OVP trip point and OCP trip point will be displayed in the display area.

4. While viewing the values displayed on the panel, use the VOLTAGE and CURRENT knobs to program the OVP and OCP trip points you'd like to write to memory.

5. Press OCP•OVP again. The present UVL trip point is displayed.

6. While viewing the value displayed on the panel, turn the VOLTAGE knob to program the UVL trip point you want to write to memory.

7. Press SHIFT+ the memory key (A, B, or C) to which you want to save the settings. Hold the keys down until their LEDs turn on.

The PRESET A, PRESET B, or PRESET C LED in the display area—whichever one corresponds to the memory entry that you selected—lights to indicate that the preset memory entry has been saved.

You can save preset memory entries when the output is on and the measured value display is being shown (the SET key LED is off). After you save a preset memory entry, press SET to view the preset memory values.

Chapter 2 Basic Functions

Recalling Preset Memory Entries

You can recall preset memory entries from the measured value display (when the SET key LED is off) and from the setting display (when the SET key LED is lit). If the output is on, the values in the preset memory entry are applied to the output the moment that the preset memory entry is recalled.

There are two methods to recall a preset memory entry. One method is to display the saved contents for confirmation and then recall (CF04: on). The other is to recall immediately without displaying the contents (CF04: oFF).

When you recall a preset memory entry, the following items are set to their factory default settings.

• Constant current control using an Vext or Rext (CF05: oFF)

• Constant voltage control using an Vext or Rext (CF06: oFF)

• Output on/off control using an external contact (CF09: oFF)

• Current setting limit (CF14: on)

• Voltage setting limit (CF15: on)

Complete the following steps to display the saved contents for confirmation and recall.

1. Press SHIFT+ the memory key (A, B, or C) from which you want to recall the preset memory entry.

The SET LED and the contents (voltage and current) of the loaded preset memory that are shown in the display area blink. If you press another memory key, the contents of the corresponding memory appear blinking.

Note This is convenient when you want to view the contents that have been saved

to memory.

2. Check the displayed settings, and then press SET. The SET LED and the LED that corresponds to the loaded preset memory entry both light,

and the set voltage and current are displayed on the panel.

Note Press OCP•OVP, CONFIG, or PWR DSPL to cancel the recall operation.

Complete the following steps to recall without displaying the saved contents.

1. Use the CONFIG settings to set the RMX programmable power supply to hide the saved contents of preset memory entries (CF04: oFF).

Note This is convenient when you know the contents that have been saved to

memory.

2. While holding down the SHIFT key, press the appropriate memory key (A, B, or C). The LED that corresponds to the preset memory entry that you have loaded (PRESET A,

B, or C) lights.

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RMX Programmable Power Supplies User Manual

Lit

Locking Panel Operations (Key Lock)

The RMX programmable power supply key lock function prevents you from accidentally changing the settings.

Figure 2-29. Key Lock Display Example

When the keys are locked (when the LOCK LED is lit), only the OUTPUT key is valid.

1. Configure all the settings, such as the output voltage and output current, as necessary.

2. Hold down LOCK (SHIFT+LOCAL) until the LOCK LED in the display area lights.

When the LOCK LED lights, the keys are locked.

To unlock the keys, hold down LOCK again (SHIFT+LOCAL) until the LOCK LED turns off.

Bleeder On/Off Feature

You can turn the bleeder circuit on and off. Turn the bleeder circuit off when you do not want the internal bleeder circuit to sink output current. When you connect a battery, you can prevent excessive electrical discharges by turning the bleeder circuit off.

When using master-slave parallel operation or series operation, use the same bleeder circuit settings on all connected units.

Depending on whether the bleeder circuit is on or off, the sink current and the fall time of output voltage when an external voltage source is connected will vary. The sink current or fall time indicated here is a standard value.

Caution Risk of electric shock. Set the bleeder on/off setting to “on” before you

touch the output terminals. Even if you turn the output off or turn the POWER switch off, if the bleeder on/off setting is set to “oFF” the voltage that was present when the output was on will remain at the output terminals.

Chapter 2 Basic Functions

Table 2-4. Sink Current From an External Source when Bleeder is On/Off

Model

RMX-4120/ RMX-4124

Even when the bleeder is on, the sink current decreases gradually at output terminal voltages lower than

Circuit

ON 704 mA 667 mA 630 mA 593 mA 556 mA 519 mA

OFF 0.2 mA 0.4 mA 0.6 mA 0.8 mA 1.0 mA 1.2 mA

Bleeder

5 V

OUT

10 V

OUT

Sink Current

15 V

OUT

20 V

OUT

25 V

OUT

30 V

this voltage. If the output terminal voltage is near 0 V, hardly any current will be sunk even when the bleeder is on.

Note V

= Output terminal voltage.

OUT

Table 2-5. Sink Current From an External Source when Bleeder is On/Off

Sink Current

50 V

OUT

100 V

OUT

200 V

OUT

230 V

Model

RMX-4122

Bleeder

Circuit

10 V

OUT

20 V

OUT

ON 746 mA 549 mA 307 mA 177 mA 96 mA 84 mA

OFF 0.2 mA 0.3 mA 0.7 mA 1.3 mA 2.5 mA 2.9 mA

RMX-4126

ON 1097 mA 808 mA 451 mA 260 mA 140 mA 123 mA

OFF 0.3 mA 0.5 mA 1.3 mA 2.5 mA 5.0 mA 5.8 mA

Even when the bleeder is on, the sink current decreases gradually at output terminal voltages lower than this voltage. If the output terminal voltage is near 0 V, hardly any current will be sunk even when the bleeder is on.

OUT

Note V

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= Output terminal voltage.

OUT

RMX Programmable Power Supplies User Manual

OUT

80 V

OUT

70 V

OUT

60 V

OUT

50 V

OUT

40 V

Sink Current

OUT

30 V

OUT

20 V

OUT

650 V

OUT

600 V

OUT

500 V

OUT

400 V

OUT

300 V

Sink Current

OUT

200 V

OUT

100 V

Table 2-6. Sink Current From an External Source when Bleeder is On/Off

OUT

10 V

OUT

5 V

Table 2-7. Sink Current From an External Source when Bleeder is On/Off

= Output terminal voltage.

Circuit

Bleeder

ON 704 mA 667 mA 593 mA 519 mA 444 mA 370 mA 296 mA 222 mA 148 mA

OFF 0.2 mA 0.3 mA 0.5 mA 0.7 mA 0.9 mA 1.1 mA 1.3 mA 1.5 mA 1.7 mA

OUT

Note V

Model

RMX-4121/

RMX-4125

Even when the bleeder is on, the sink current decreases gradually at output terminal voltages lower than this voltage. If the output terminal voltage is near

0 V, hardly any current will be sunk even when the bleeder is on.

OUT

50 V

OUT

20 V

= Output terminal voltage.

Circuit

Bleeder

ON 463 mA 325 mA 217 mA 130 mA 93 mA 73 mA 59 mA 50 mA 47 mA

OFF 0.2 mA 0.5 mA 0.9 mA 1.7 mA 2.5 mA 3.4 mA 4.2 mA 5.0 mA 5.5 mA

OUT

Note V

Model

RMX-4123/

RMX-4127

Even when the bleeder is on, the sink current decreases gradually at output terminal voltages lower than this voltage. If the output terminal voltage is near

0 V, hardly any current will be sunk even when the bleeder is on.

Chapter 2 Basic Functions

Fall Time

This is the time period for the rated output voltage to fall from 90% to 10% when the output is changed from on to off under no load conditions.

Table 2-8. Fall Time of the Output Voltage when the Bleeder is Off

Model Fall Time

RMX-4120 310 seconds

RMX-4121 280 seconds

RMX-4122 110 seconds

RMX-4123 70 seconds

RMX-4124 490 seconds

RMX-4125 460 seconds

RMX-4126 130 seconds

RMX-4127 100 seconds

Switching from Remote Mode to Local Mode

When the RMX programmable power supply is being controlled remotely, the REMOTE LED in the display area lights.

To switch the RMX programmable power supply to local mode from the front panel, press LOCAL.

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RMX Programmable Power Supplies User Manual

Factory Default Settings (Initialization)

If you hold down SHIFT+LOCAL while you turn the POWER switch on, the RMX programmable power supply will be reset to the factory default settings.

The factory default settings are shown in the following table.

Table 2-9. Basic Settings

Basic Item Parameter Description

Output Voltage 0 V

Output Current 105% of the rated output current

OVP (Overvoltage Protection) 112% of the rated output current

OCP (Overcurrent Protection) 112% of the rated output current

UVL (Undervoltage Limit) 0 V

Table 2-10. CONFIG Settings

Parameter

Number CONFIG Parameter Parameter Description

CF01 Master-slave parallel operation parameter 1 (independent operation)

CF02

CF03 Method for clearing OHP, FAN, and

CF04

CF05

CF06

CF07

CF08 Range during voltage and current

CF09

CF10

CF11 Bleeder on/off parameter ON (bleeder circuit is on)

Power-on status parameter SAFE (panel settings that were in use the

last time the power was turned off)

SAFE (do not clear the alarm

AC-FAIL alarms

automatically)

Memory content display parameter ON (displayed)

CC control using an Vext or Rext OFF

CV control using an Vext or Rext OFF

CV/CC control range parameter LO (0 to 5 V)

LO (0 to 5 V)

monitoring

External control parameter for turning

OFF

output on and off

External control logic parameter for

LO (a LOW signal turns output on)

turning output on and off

Chapter 2 Basic Functions

Table 2-10. CONFIG Settings (Continued)

Parameter

Number CONFIG Parameter Parameter Description

CF12

Output-on startup state parameter CV (CV is prioritized)

CF13 Detection time of OCP activation 0 ms

CF14

CF15

Current setting limit ON (the setting is limited)

Voltage setting limit ON (the setting is limited)

CF16 Panel display brightness setting 7

CF17 Communication monitor timer setting OFF (Communication monitoring timer off)

CF18 Unused —

CF19

Display setting on slave units for

OFF (not displayed on slave units)

master-slave parallel operation

CF20 LAN interface parameter LAN (the LAN interface will be used)

CF21 Command language parameter SCPI

CF22 Emulation parameter during remote

control

CF23 SCPI communication error display

NONE (RMX programmable power supply commands)

OFF (not displayed)

parameter

CF24 Multichannel (VMCB) domain number 0 (the multichannel function is not used)

CF25 Multichannel (VMCB) channel number 0 (the RMX programmable power supply is

used as a master unit on the multichannel network)

CF41 IP address assignment method DHCP: ON

AUTO IP: ON MANUAL IP: OFF

CF47 SCPI-RAW protocol TCP port number 5025

CF52 RS232C baud rate parameter 19.2 (kbit/s)

You can only specify this parameter when the RMX programmable power supply is being used as a master unit.

0 to 0.5 V or shorted.

You can only specify this parameter when the RMX programmable power supply is being used as a slave unit.

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External Control

This chapter explains external control and external monitoring using the J1 connector.

Overview

You can use the J1 connector on the rear panel of the RMX programmable power supply to perform the following types of external control.

• Output voltage control (Controlled using an external voltage or external resistance)

• Output current control (Controlled using an external voltage or external resistance)

• Turning output on and off using an external contact

• Output shutdown control using an external contact

• Clearing alarms using an external contact

• Monitoring operation modes

About the J1 Connector

Use the included J1 connector plug kit for connecting to the J1 connector. RMX programmable power supplies are supplied with a connector cover that fits over the entire sensing, J1, and J2 connectors. For safety reasons, be sure to attach the connector cover when you use the RMX programmable power supply.

Figure 3-1. Connector Cover

Plug kit 749809-9 DB25 is included for connecting to the J1 connector.

Chapter 3 External Control

Unlock and open the core

30 mm

Attaching the J1 Cable Core

To connect to the J1 connector, requires a core on the cable for connection. The core is not included. Use an appropriate core.

1. Unlock the snap-on core and open to split.

Figure 3-2. Unlocking the Snap-on Core

2. Wrap the cable twice around either half of the open core. Wrap the wire so that the distance between the core and the J1 connector is within 30 mm.

Figure 3-3. Wrapping the Cable Around the Open Core

3. Close the core keeping the J1 cable from being wedged in between. Check that the core is securely locked.

Figure 3-4. Unlocking the Snap-on Core

Core

To connection

To J1 connector

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RMX Programmable Power Supplies User Manual

12345

6789

10111213

141516171819202122232425

Figure 3-5. J1 Connector Pinout

Table 3-1. J1 Connector Signals

Pin Signal Name Description

1 PRL ON COM Common for pin 16.

2 N.C. Not connected.

3 N.C. Not connected.

4 N.C. Not connected.

5 ALM CLR Alarm clear terminal

Alarms are cleared when a LOW (0 to 5 V) or short-circuit is applied to this terminal.

6 SHUT DOWN Output shutdown control terminal. The output is turned off when a

LOW (0 to 0.5 V) or short-circuit is applied to this terminal.

7 PRL IN- Negative input terminal for master-slave parallel operation.

8 PRL IN+ Positive input terminal for master-slave parallel operation.

9 PRL COMP IN Correction signal input terminal for master-slave parallel operation.

10 A COM External signal common for pins 5 to 9, 11 to 13, 20 to 22, 24, and 25.

During remote sensing, this is the negative electrode (-S) of sensing input. When remote sensing is not being performed, this is connected to the negative output.

11 PRL OUT+ Positive electrode output terminal for master-slave parallel operation.

12 PRL COMP OUT Correction signal output terminal for master-slave parallel operation.

13 I SUM Current signal terminal for master-slave parallel operation.

14 N.C Not connected.

15 N.C. Not connected.

16 PRL ON On during master-slave parallel operation (output through an

open-collector photocoupler).

17 N.C. Not connected.

Chapter 3 External Control

Table 3-1. J1 Connector Signals (Continued)

Pin Signal Name Description

18 OUT ON/OFF CONT Output on/off terminal.

On when set to LOW (0 to 0.5 V) or shorted (CF10: Lo); Off when set to HIGH (4.5 or 5 V) or open (CF10: Lo) On when set to HIGH (4.5 to 5 V) or open (CF10: Hi); Off when set to LOW (0 or 0.5 V) or shorted (CF10: Hi).

19 A COM External signal common for pins 5 to 9, 11 to 13, 20 to 22, 24, and 25.

During remote sensing, this is the negative electrode (-S) of sensing input. When remote sensing is not being performed, this is connected to the negative output.

20 REF OUT External resistance control terminal; 5.25 V (CF07: Lo) or 10.5 V

(CF07: Hi). The maximum output current 2.5 mA.

21 I PGM Terminal used to control the output current with an external voltage

or external resistance. 0 to 5 V; 0 to 100% of the rated output current (CF07: Lo). 0 to 10 V; 0 to 100% of the rated output current (CF07: Hi).

22 V PGM Terminal used to control the output voltage with an external voltage

or external resistance. 0 to 5 V; 0 to 100% of the rated output voltage (CF07: Lo). 0 to 10 V; 0 to 100% of the rated output voltage (CF07: Hi).

23 A COM External signal common for pins 5 to 9, 11 to 13, 20 to 22, 24, and 25.

During remote sensing, this is the negative electrode (-S) of sensing input. When remote sensing is not being performed, this is connected to the negative output.

24 I MON Output current monitor.

0 to 100% of the rated output current is generated as a voltage between 0 and 5 V (CF08: Lo) or a voltage between 0 and 10 V (CF08: Hi).

25 V MON Output voltage monitor.

0 to 100% of the rated output voltage is generated as a voltage between 0 and 5 V (CF08: Lo) or a voltage between 0 and 10 V (CF08: Hi).

Open collector output: Maximum voltage of 30 V and maximum current of 8 mA.

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RMX Programmable Power Supplies User Manual

J2 connector

Strip 7 mm (0.28 inches) of the cable covering, and then insert the cable here.

Use this screw to fix the wires in place so that they do not come loose.

About the J2 Connector

The J2 connector can be split into two parts: the socket and the detachable plug. The plug is attached to the J2 socket when the RMX programmable power supply ships from the factory. If you damage or lose the detachable plug, contact National Instruments for a replacement.

To minimize the influence of noise, NI recommends using shielded twisted pair wires to make connections.

Figure 3-6. J2 Connector

Chapter 3 External Control

Figure 3-7. J2 Connector Pinout

Table 3-2. J2 Connector Signals

Pin Signal Description

1 CV STATUS On when the RMX programmable power supply is in

CV mode. (open-collector output from a photocoupler)

2 CC STATUS On when the RMX programmable power supply is in

CC mode. (open-collector output from a photocoupler)

3 ALM STATUS On when a protection function (OVP/OVP2/ OCP/ OHP/

OHP2/ FAN/ SEN/ACAC-FAIL) is activated. (output through an open-collector photocoupler)

4 PWR ON STATUS Outputs a low level signal when power is turned on

(output through an open-collector photocoupler)

5 OUT ON STATUS On when output is on (output through an open-collector

photocoupler)

6 to 9 STATUS COM Status signal common for pins 1 to 52.

The above signal output circuit is protected with reinforced insulation from the MAINS.

Open collector output: Maximum voltage of 30 V and maximum current of 8 mA.

That status common is floating (isolation voltage of 60 V or less), it is isolated from the control circuit.

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RMX Programmable Power Supplies User Manual

Output Terminal Insulation

Caution Risk of electric shock. For safety reasons, even if the output terminal is

grounded, secure reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply for the output terminals (including sensing terminals) and load cables. Refer to Appendix A,

Specifications, for the isolation voltage of your model.

If cables with sufficient voltage rating cannot be obtained, use insulation tubes to secure reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply.

Confirm the voltage between any output terminal and ground is lower than the isolation voltage of the RMX power supply.

The signal cable may burn out. If the RMX programmable power supply is to be controlled through an external voltage (Vext), do not ground the external voltage (leave it floating).

The cable and load that are connected to the output terminal (including the sensing terminal) must have a reinforced or double insulation with a capacity that is greater than or equal to the isolation voltage of the RMX programmable power supply with respect to the chassis. Isolation voltage indicates the maximum allowed voltage that appears across the output terminal of the power supply unit and the protective conductor terminal (chassis terminal).

When the Output Terminal is Not Grounded (Floating)

The output terminal of the RMX programmable power supply is isolated from the protective conductor terminal. If you connect the GND wire of the power cord to the ground terminal of the switchboard, the chassis of the RMX programmable power supply is set to ground potential.

Pins 5 to 13 (for external control and parallel operation) and 18 to 25 (for external control and output monitoring) of the rear panel J1 connector are at approximately the same electric potential as the RMX programmable power supply negative output terminal. Cables and devices that are connected to these pins must have a reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply.

Chapter 3 External Control

+ –

+S –S

–

+ –

21 22

23 24 25

AC INPUT

DC OUTPUT

SENS

Load

Rext

RMX

Vext

Because the output terminal is floating, the section shown on a gray background must have a reinforced or double insulation with a capacity greater than or equal to the RMX isolation voltage.

5 6

18 19

Approximately the same potential as the negative output terminal

Isolated

Figure 3-8. Output Terminal is Not Grounded (Floating)

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RMX Programmable Power Supplies User Manual

When the Output Terminal is Grounded

If the positive output terminal is connected to the chassis terminal, the positive output terminal is at ground potential. The cable and load that are connected to the output terminal (including the sensing terminal) will only require an insulation capacity that is greater than or equal to the maximum output voltage of the RMX programmable power supply with respect to the chassis. There is no need to provide insulation that is greater than or equal to the isolation voltage of the RMX programmable power supply.

The same holds true when the negative terminal is connected to the chassis terminal. The cable and load require a reinforced or double insulation with a capacity that is greater than or equal to the maximum output voltage of the RMX programmable power supply.

For safety reasons, connect one of the output terminals to the chassis terminal unless your application requires the output terminals to be floating.

Chapter 3 External Control

+ –

+S –S

–

+ –

21 22

23 24 25

AC INPUT

DC OUTPUT

SENS

Load

Rext

RMX

Vext

Because the positive output terminal is at ground potential, the section shown on a gray background must have a reinforced or double insulation with a capacity greater than or equal to the maximum output voltage relative to the chassis.

Chassis terminal

5 6

18 19

Approximately the same potential as the negative output terminal

Isolated

Figure 3-9. Output Terminal is Grounded

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RMX Programmable Power Supplies User Manual

Cautions When Controlling the Output with an External Voltage (Vext)

You must take careful precautions when connecting external equipment to the J1 connector to make sure you do not unknowingly short both output terminals to ground.

Connect the cables so that output is not shorted. See the following figures for examples of shorted output.

Caution The Vext cable must not be referenced/connected to the chassis ground

terminal. The signal must be floating relative to ground. Connecting/referencing this signal to ground may cause the cable to be damaged. Refer to Figures 3-10 and 3-11 for more information.

If you are connecting the shield to the Vext side, do not connect the shield to the output terminal of the RMX programmable power supply.

Figure 3-10. Connection Where the Output is Shorted by the Grounding of Vext

Vext RMX

–

Prohibited

2-core shielded wire

Approximately the same electric potential as the negative output terminal

Ground the positive output terminal.

–

Output is shorted by the grounding of Vext, causing current to flow.

Figure 3-11. Connection Where the Output is Shorted by the Shield

Vext RMX

–

2-core shielded wire

Prohibited

Approximately the same electric potential as the negative output terminal

Ground the positive output terminal.

–

Output is shorted by the shield, causing current to flow.

Chapter 3 External Control

Controlling the Output Voltage

This section explains how to control the output voltage using an external voltage (Vext) or an external variable resistor (Rext) of approximately 10 kΩ.

If no load is connected, it takes some time for the output voltage to decrease. There may be a delay between when you request a new voltage with Vext or Rext and when it shows up on the output terminals.

Caution Risk of electric shock. If neither output terminal is tied to chassis ground,

the reinforced or double insulation of Vext or Rext and the connected cable must be greater than or equal to the isolation voltage of the RMX programmable power supply. Refer to Appendix A, Specifications, for the isolation voltage of your model.

If one of the output terminals is connected to chassis ground, the insulation of Vext or Rext and the connected cable must have a reinforced or double insulation with a capacity greater than or equal to the maximum output voltage relative to the chassis

When using shielded cables for the connection, for uncovered sections of the shielded cables, use insulation tubes to secure reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply.

Control Using an External Voltage (Vext)

To use an external voltage (Vext) to control the output voltage, set CONFIG setting CF06 to ON to enable control of the output voltage using an external voltage.

The output voltage (Eo) varies in the range of 0 to the rated output voltage (Ertg) when the external voltage (Vext) is changed in the range of 0 to 5 V (CF07: Lo) or in the range of 0 to 10 V (CF07: Hi).

External voltage (Vext)

0 to 5 V (CF07: Lo)

Eo = Ertg × Vext/5 (in V) Vext = 5 × Eo/Ertg (in V)

Caution The Vext cable must not be referenced/connected to the chassis ground

terminal. The signal must be floating relative to ground. Connecting/referencing this signal to ground may cause the cable to be damaged. Refer to Figures 3-10 and 3-11 for more information.

Pay careful attention to the polarity of Vext. Do not apply a voltage of 10.5 V or greater, or a reverse voltage across the external voltage control pins.

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Eo = Ertg × Vext/10 (in V) Vext = 10 × Eo/Ertg (in V)

External voltage (Vext)

0 to 10 V (CF07: Hi)

RMX Programmable Power Supplies User Manual

External Voltage (Vext) Connection

Use a low-noise, stable voltage source for Vext. The noise in Vext is multiplied by the amplification factor of the RMX programmable power supply and appears in the output. A noisy Vext source can cause the output ripple noise of the RMX power supply to not meet its specifications.

To reduce the noise on the output, connect a 2-core shielded wire or a twisted-pair wire, and keep the wire as short as possible. If the wiring between the RMX programmable power supply and the external contact is long, it becomes easy for noise to influence the operation of the RMX programmable power supply. Even if you use cables that are designed to suppress noise, the RMX programmable power supply may not operate properly.

Figure 3-12. CV Vext Connection.

Vex t

2-core shielded wire or twisted-pair wire

+ –

Output terminals

RMX

If you use a shielded cable, connect the shield to the negative output terminal. Refer to Cautions

When Controlling the Output with an External Voltage (Vext) if the shield needs to be connected

to the Vext side. Use pins 22 and 23 of the J1 connector.

Control Using an External Resistance (Rext)

An external variable resistor (Rext) can be used along with the Reference Voltage Output (pin 20 on the J1 connector) to externally control the output voltage of the power supply. You can use this method to set the output voltage (Eo) to a value from 0% to 105% of the rated output voltage (Ertg).

To use an external resistance (Rext) to control the output voltage, set CONFIG setting CF06 to ON to enable control of the output voltage using an external resistor.

External voltage (Vext)

0 to 5 V (CF07: Lo)

Eo = Ertg × Vext/5 (in V) Vext = 5 × Eo/Ertg (in V)

External voltage (Vext)

0 to 10 V (CF07: Hi)

Eo = Ertg × Vext/10 (in V) Vext = 10 × Eo/Ertg (in V)

Chapter 3 External Control

2-core shielded wire or twisted-pair wire

Wiper

Output terminals

RMX

Rext

Vext

External Resistance (Rext) Connection

For Rext, use a resistor that is rated at approximately 10 kΩ, 1/2 W or greater, that has a low temperature coefficient, and that will change little over time. Examples of such resistors are metal film or wire wound resistors.

Figure 3-13. CV Rext Connection.

If you use a shielded cable, connect the shield to the negative output terminal. Use pins 20, 22, and 23 of the J1 connector.

Controlling the Output Current

This section explains how to control the output current using an external voltage (Vext) or an external variable resistor of approximately 10 kΩ (Rext).

Caution Risk of electric shock. If neither output terminal is tied to chassis ground,

the reinforced or double insulation of Vext or Rext and the connected cable must be greater than or equal than or equal to the isolation voltage of the RMX programmable power supply. Refer to Appendix A, Specifications, for the isolation voltage of your model.

When using shielded cables for the connection, for uncovered sections of the shielded

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cables, use insulation tubes to secure reinforced or double insulation with a capacity greater than or equal to the isolation voltage of the RMX programmable power supply.

RMX Programmable Power Supplies User Manual

2-core shielded wire or twisted-pair wire

Vex t

+ –

Output terminals

RMX

Control Using an External Voltage (Vext)

To use an external voltage (Vext) to control the output current, set CONFIG setting CF05 to ON to enable control of the output current using an external voltage.

The output current (Io) varies in the range of 0 to the rated output current (Irtg) when the external voltage (Vext) is changed in the range of 0 to 5 V (CF07: Lo) or in the range of 0 to 10 V (CF07: Hi).

External voltage (Vext)

0 to 5 V (CF07: Lo)

Io = Irtg × Vext/5 (in A) Vext = 5 × Io/Irtg (in A)

Caution The Vext cable must not be referenced/connected to the chassis ground

Io = Irtg × Vext/10 (in A) Vext = 10 × Io/Irtg (in A)

External voltage (Vext)

0 to 10 V (CF07: Hi)

terminal. The signal must be floating relative to ground. Connecting/referencing this signal to ground may cause the cable to be damaged. Refer to Figures 3-10 and 3-11 for more information.

Pay careful attention to the polarity of Vext. Do not apply a voltage of 10.5 V or greater, or a reverse voltage across the external voltage control pins.

External voltage source (Vext) connection

Connect a low-noise, stable voltage source to Vext. The noise in Vext is multiplied by the amplification factor of the RMX programmable power supply and appears in the output. A noisy Vext source can cause the output ripple noise of the RMX power supply to not meet its specifications.

Figure 3-14. CC Vext Connection.

Chapter 3 External Control

2-core shielded wire or twisted-pair wire

Output terminals

RMX

Rext

Vext

Wiper

If you use a shielded cable, connect the shield to the negative output terminal. Refer to Cautions

When Controlling the Output with an External Voltage (Vext) if the shield needs to be connected

to the Vext side. Use pins 21 and 23 of the J1 connector.

Control Using an External Resistance (Rext)

An external variable resistor (Rext) can be used along with the Reference Voltage Output (pin 20 on the J1 connector) to externally control the output current of the power supply. You can use this method to set the output current (Io) to a value from 0% to 105% of the rated output current (Irtg).

To use an external resistance (Rext) to control the output current, set CONFIG setting CF05 to ON to enable control of the output current using an external resistor.

External voltage (Vext)

0 to 5 V (CF07: Lo)

Io = Irtg × Vext/5 (in A) Vext = 5 × Io/Irtg (in A)

Io = Irtg × Vext/10 (in A) Vext = 10 × Io/Irtg (in A)

External voltage (Vext)

0 to 10 V (CF07: Hi)

External Resistance (Rext) Connection

To reduce the noise on the output, connect a 2-core shielded wire or a twisted-pair wire, and keep the wire as short as possible. If the wiring is long, it becomes easy for noise to influence the operation of the RMX programmable power supply. Even if you use wires that are designed to suppress noise, the RMX programmable power supply may not operate properly.

Figure 3-15. CC Rext Connection.

If you use a shielded cable, connect the shield to the negative output terminal. Use pins 20, 21, and 23 of the J1 connector.

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RMX Programmable Power Supplies User Manual

Controlling the Output On and Off States

This section explains how to use an external contact to control the output on and off states.

Caution Risk of electric shock. If neither output terminal is tied to chassis ground,

the reinforced or double insulation of the external contact (S) and the connected cable must be greater than or equal to the isolation voltage of the RMX programmable power supply. Refer to Appendix A, Specifications, for the isolation voltage of your model.

If one of the output terminals is connected to chassis ground, the insulation of external contact (S) and the connected cable must have a reinforced or double insulation with a capacity greater than or equal to the maximum output voltage relative to the chassis.

To reduce the noise on the output, connect a 2-core shielded wire or a twisted pair wire, and keep the wire as short as possible. If the wiring is long, it becomes easy for noise to influence the operation of the RMX programmable power supply. Even if you use wires that are designed to suppress noise, the RMX programmable power supply may not operate properly. If you use a shielded cable, connect the shield to the negative output terminal.

Set CONFIG parameter CF09 to ON to use an external contact to control the output on and off state of the device.

• Turn the output on with a low signal (CF10: Lo). Output is turned on when a LOW (0 to

0.5 V) or short-circuit is applied between pin 18 and 19 of the J1 connector.

• Turn the output on with a high signal (CF10: Hi). Output is turned on when a HIGH (4.5 to 5 V) or open-circuit is applied between pin 18 and 19 of the J1 connector.

When the external contact has put the output into the off state, the OUTPUT key on the front panel will not have any effect on the output signal. When the external contact has put the output into the on state, the OUTPUT key on the front panel can still turn the output off and on. Refer to Figure 3-16 for more information about how a high signal is used to turn the output on.

Chapter 3 External Control

Off

H = On

L = Off

▼ represents that the OUTPUT key has been pressed.

The external contact has been used to turn output on, so the OUTPUT key is enabled.

External contact

The OUTPUT key is disabled. Even if you press it, output is not generated.

To use the external contact to turn output on again, first turn the output off.

Output

2-core shielded wire or twisted-pair wire

Output terminals

RMX

Figure 3-16. Controlling the Output On and Off States.

External Contact Connection

Connect your external contact between pins 18 and 19 of the J1 connector. The open-circuit voltage across pins 18 and 19 is approximately 5 V. The short-circuit current across pins 18 and 19 is approximately 0.5 mA.

Figure 3-17. External Contact Connection.

Use external contacts that have a contact rating of 0.5 mA or more at 5 VDC. If two or more units are floating and you are using a single external contact to turn output on and off for all the units, use a relay or similar device for the external contact signal to isolate the signal transmitted to each unit.

Long-Distance Wiring

When you are wiring over a great distance, use a small relay and extend the coil side of the relay.

Figure 3-18. Long Distance Wiring.

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Extend this line.

Relay

RMX Programmable Power Supplies User Manual

Controlling Output Shutdown

This section explains how to use an external contact to turn output off. This functionality differs from the Controlling the Output On and Off States external control pin, because recovering from an output shutdown requires the unit to be power cycled.

Caution Risk of electric shock. If neither output terminal is tied to chassis ground,

If one of the output terminals is connected to chassis ground, the insulation of the external contact and the connected cable must have a reinforced or double insulation with a capacity greater than or equal to the maximum output voltage relative to the chassis.

If you use a shielded cable, connect the shield to the negative output terminal.

If you apply a LOW (0 to 0.5 V) or short-circuit pin 6 to pin 19 of the J1 connector, the output shuts down.

To recover, set pin 6 of the J1 connector to HIGH (4.5 to 5 V) or open the pin, and then turn the POWER switch off and then on.

Output Shutdown Connection

Connect your external contact between pins 6 and 19 of the J1 connector. The open-circuit voltage across pins 6 and 19 is approximately 5 V. The short-circuit current across pins 6 and 19 is approximately 0.5 mA.

Use external contacts that have a contact rating greater than or equal to 0.5 mA at 5 VDC.

Figure 3-19. Output Shutdown Connection.

2-core shielded wire or twisted-pair wire

Output terminals

RMX

If two or more units are floating, and you are using a single external contact to turn output off for all the units, use a relay or similar device for the external contact signal to isolate the signal transmitted to each unit.

Long-Distance Wiring

When you are wiring over a great distance, use a small relay and extend the coil side of the relay.

Figure 3-20. Long Distance Wiring.

Extend this line.

Relay

Controlling the Clearing of Alarms

This section explains how to use an external contact to clear alarms.

Caution Risk of electric shock. If neither output terminal is tied to chassis ground,

RMX Programmable Power Supplies User Manual

If you use a shielded cable, connect the shield to the negative output terminal. If you apply a LOW (0 to 0.5 V) or short-circuit to pin 5 of the J1 connector, the alarms will be cleared.

Alarm Clear Connection

Connect your external contact between pins 5 and 19 of the J1 connector. The open-circuit voltage across pins 5 and 19 is approximately 5 V. The short-circuit current across pins 5 and 19 is approximately 0.5 mA.

Use external contacts that have a contact rating greater than or equal to 0.5 mA at 5 VDC.

Figure 3-21. Alarm Clear Connection.

2-core shielded wire or twisted-pair wire

Output terminals

RMX

If two or more units are floating, and you are using a single external contact to clear alarms, use a relay or similar device for the external contact signal to isolate the signal transmitted to each unit.

Chapter 3 External Control

Long-Distance Wiring

When you are wiring over a great distance, use a small relay and extend the coil side of the relay.

Figure 3-22. Long Distance Wiring.

Extend this line.

Relay

External Monitoring

The J1 connector has monitor outputs for the output voltage and the output current.

Table 3-3. External Monitoring of J1 Connector Output Voltage and Output Current

Pin Signal Name Description

10, 19, 23, A COM Remote control input common

Output monitor common

25 V MON Monitor output of output voltage

0 to approximately 5 V (CF08: Lo) or 0 to approximately 10 V (CF08: Hi) for 0 to the rated output voltage

24 I MON Monitor output of output current

0 to approximately 5 V (CF08: Lo) or 0 to approximately 10 V (CF08: Hi) for 0 to the rated output current

Caution Shorting V MON and I MON to A COM may damage the RMX

programmable power supply.

Monitor Output Rating

• Output impedance: 1 kΩ or less. Maximum output current: Approximately 10 mA.

The monitor output signals are used to monitor the DC voltage (mean value). They cannot be used to accurately monitor the AC components (such as ripple and transient response waveform) of the actual output voltage or current.

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RMX Programmable Power Supplies User Manual

External Monitoring of the Operation Status

The J2 connector has status outputs that can be used to externally monitor the operation status of the RMX programmable power supply. The following five items make up the status outputs.

The outputs are open collector outputs of photocouplers; they are isolated from the internal circuits of the RMX programmable power supply. The status common is floating (that is, it has an isolation voltage of less than or equal to 60 V).

The above signal output circuit is protected with reinforced insulation from the MAINS.

The maximum ratings of the signal terminals are as follows:

• Maximum voltage: 30 V.

• Maximum current (sink): 8 mA.

Table 3-4. External Monitoring of the J2 Connector Signal Terminals Operation Status

Pin Signal Description Circuit

6-9 STATUS COM This is the status output common.

This is the photocoupler emitter output.

1 CV STATUS This is set to low level when the RMX

programmable power supply is in constant voltage mode. This is the photocoupler open collector output.

2 CC STATUS This is set to low level when the RMX

programmable power supply is in constant current mode. This is the photocoupler open collector output.

3 ALM STATUS This is set to low level when a protection

function (OVP/OVP2/ OCP/ OHP/ OHP2/ FAN/ SEN/ AC-FAIL/ SD) is activated. This is the photocoupler open collector output.

4 PWR ON STATUS This is set to low level when the RMX

programmable power supply is turned on (PWR ON STATUS). This is the photocoupler open collector output.

5 OUT ON STATUS This is set to low level when the output is

turned on. This is the photocoupler open collector output

6 to 9

National Instruments RMX-4120, RMX-4121, RMX-4122, RMX-4124, RMX-4125 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

RMX Programmable Power Supplies User Manual

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Copyright

End-User License Agreements and Third-Party Legal Notices

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Export Compliance Information

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

Contents

Attaching the Connector Cover

Figure 1-1. Connector Cover

Connecting the Power Cord

RMX-4120/4121/4122/4123 (750 W Models)

Necessary Cable

RMX-4124/4125/4126/4127 (1500 W Models)

Necessary Cable

Switchboard Breaker Requirements

Figure 1-2. Switchboard Diagram

Connection Procedure

Figure 1-3. Attaching the Crimping Terminal

Figure 1-4. Connecting the Power Cord

Turning the Power On

Turning the POWER Switch On

Figure 1-5. Power On Information Display

Inrush Current

Turning the POWER Switch Off

Rack Mounting

Load Considerations

Loads with Peak Current or Pulse-Shaped Current

Figure 1-6. Loads with Peak Current or Pulse-Shaped Current

Loads that Generate Reverse Current to the Power Supply

Figure 1-7. Loads with Accumulated Energy

Loads with Accumulated Energy

Figure 1-8. Loads with Accumulated Energy

Load Cables

Table 1-1. Current Capacity of Heat-resistant Vinyl Wires

Protecting Against Noise

Cabling Considerations When Using Remote Sensing

Connecting to the Output Terminals

Figure 1-9. RMX-4125 Output Terminal

Figure 1-10. RMX-4120/4121/4124/4125

Figure 1-11. RMX-4122/4123/4126/4127

Figure 1-12. Connection Using M8 Bolt Set for RMX-4120/4121/4124/4125

Figure 1-13. Connection Using M5 Bolt Set for RMX-4122/4123/4126/4127

Attaching the Output Terminal Cover

Figure 1-14. Attaching Bottom Half of the OUTPUT Terminal Cover

Figure 1-15. Aligning Both Halves of the OUTPUT Terminal Cover

Figure 1-16. Attaching the OUTPUT Terminal Cover

Sensing

Figure 1-17. Connector Cover

Figure 1-18. Terminal Connector

Figure 1-19. Sensing Cable Connections

Table 1-2. Sensing Terminals and Functions

Local Sensing

Figure 1-20. Local Sensing

Remote Sensing

Figure 1-21. Remote Sensing

Figure 1-22. Bottom Cover with Band

Figure 1-23. Sensing Wire Assembly

Figure 1-24. Connector Cover Assembly

Connecting an Electrolytic Capacitor Across the Load

Table 1-3. Electrolytic Capacitor with RMX Programmable Power Supplies

Inserting a Mechanical Switch Between the RMX Programmable Power Supply and the Load

Figure 1-25. Mechanical Switch in a Sensing Cable

Accessories

Parallel Operation Signal Cable

Figure 1-26. Parallel Operation Signal Cable

Measured Value Display and Setting Display

Measured Value Display

Figure 2-1. Measured Value Display

Power Display

Figure 2-2. Power Display

Setting Display