Tektronix PS2520, PS2521, PS2520G, PS2521G User Manual

User Manual

PS2520, PS2520G, PS2521 & PS2521G Programmable Power Supplies

070-9196-01

pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved.

Printed in the U.S.A. T ektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000 TEKTRONIX and TEK are registered trademarks of T ektronix, Inc.

WARRANTY

Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1) year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a replacement in exchange for the defective product.

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair damage resulting from improper use or connection to incompatible equipment; or c) to service a product that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product.

THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

EC Declaration of Conformity

Tektronix Holland N.V. Marktweg 73A 8444 AB Heerenveen The Netherlands

declare under sole responsibility that the

PS2520G Programmable Power Supply

meets the intent of Directive 89/336/EEC for Electromagnetic Compatibility and Low Voltage Directive 73/23/ECC for Product Safety. Compliance was demonstrated to the following specifications as listed in the Official Journal of the European Communities:

EMC Directive 89/336/EEC: EN 55011 Class B Radiated and Conducted Emissions EN 50081-1 Emissions:

EN 60555-2 AC Power Line Harmonic Emissions

EN 50082-1 Immunity:

IEC 801-2 Electrostatic Discharge Immunity IEC 801-3 RF Electromagnetic Field Immunity IEC 801-4 Electrical Fast Transient/Burst Immunity IEC 801-5 Power Line Surge Immunity

“...conformity with the following standards:

following the provisions of the Directives of the Council of the European Union:

Low Voltage Directive 73/23/EEC: Amended by 93/68/EEC.”

EC Declaration of Conformity

Tektronix Holland N.V. Marktweg 73A 8444 AB Heerenveen The Netherlands

declare under sole responsibility that the

PS2521G Programmable Power Supply

EMC Directive 89/336/EEC: EN 55011 Class A Radiated and Conducted Emissions EN 50081-1 Emissions:

EN 60555-2 AC Power Line Harmonic Emissions

EN 50082-1 Immunity:

IEC 801-2 Electrostatic Discharge Immunity IEC 801-3 RF Electromagnetic Field Immunity IEC 801-4 Electrical Fast Transient/Burst Immunity IEC 801-5 Power Line Surge Immunity

“...conformity with the following standards:

following the provisions of the Directives of the Council of the European Union:

Low Voltage Directive 73/23/EEC: Amended by 93/68/EEC.”

General Safety Summary iii. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Preface vii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Getting Started 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Product Description 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Installation 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

General Procedure 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Basics 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Functional Overview 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Making a Control Setting 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Selecting the Output 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting the Protection Levels 8. . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting the OVP 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Resetting the OVP 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting the OCP 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting Voltage and Current Limits 9. . . . . . . . . . . . . . . . . . . . . .

Using the Keypad to Set Limits 9. . . . . . . . . . . . . . . . . . . . . .

Setting Voltage and Current Steps 10. . . . . . . . . . . . . . . . . . . .

Connecting the Outputs 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Referencing Outputs to Ground 11. . . . . . . . . . . . . . . . . . . . . .

Independent Operation 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Master/Slave Operation 18. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Enabling the Outputs 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sensing the Output Level 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storing and Recalling Settings 21. . . . . . . . . . . . . . . . . . . . . . . . . .

Storing a Setting 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Recalling an Individual Setting 22. . . . . . . . . . . . . . . . . . . . . .

Storing and Recalling a Sequence of Settings 22. . . . . . . . . . .

Setting the GPIB Address 25. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Appendix A: Specifications 27. . . . . . . . . . . . . . . . . . . . . . . . . . .

Appendix B: Maintenance 31. . . . . . . . . . . . . . . . . . . . . . . . . . .

Appendix C: Replaceable Parts 37. . . . . . . . . . . . . . . . . . . . . . .

Index 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PS2520, PS2520G, PS2521 & PS2521G User Manual

T able of Contents

List of Figures

Figure 1: Changing the Line Voltage Setting 2. . . . . . . . . . . .

Figure 2: Replacing the Line Fuse 3. . . . . . . . . . . . . . . . . . . . .

Figure 3: Front Panel Features 5. . . . . . . . . . . . . . . . . . . . . . . .

Figure 4: Rear Panel Features 6. . . . . . . . . . . . . . . . . . . . . . . .

Figure 5: SHIFT control 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6: Isolated-Ground Connection 11. . . . . . . . . . . . . . . . .

Figure 7: Examples of Independent Output Connections 13. .

Figure 8: Connecting Power Supplies in Series 14. . . . . . . . . .

Figure 9: Examples of External Series Connections 15. . . . . .

Figure 10: Connecting Power Supplies in Parallel 16. . . . . . . .

Figure 11: Examples of External Parallel Connections 17. . . .

Figure 12: Series-Tracking Operation 19. . . . . . . . . . . . . . . . . .

Figure 13: Parallel-Tracking Operation 19. . . . . . . . . . . . . . . .

Figure 14: Output On/Off Button 20. . . . . . . . . . . . . . . . . . . . .

Figure 15: Connecting the Auxiliary Sense Inputs 21. . . . . . . .

List of Tables

Table 1: Maximum Output in Series and Para Modes 18. . . .

Table 2: Operating Characteristics 27. . . . . . . . . . . . . . . . . . . .

Table 3: Electrical Characteristics 29. . . . . . . . . . . . . . . . . . . .

Table 4: Environmental Characteristics 30. . . . . . . . . . . . . . . .

Table 5: Physical Characteristics 30. . . . . . . . . . . . . . . . . . . . .

Table 6: Troubleshooting Steps 33. . . . . . . . . . . . . . . . . . . . . . .

Table 7: Error Messages 34. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 8: Standard Accessories 37. . . . . . . . . . . . . . . . . . . . . . . .

Table 9: Optional Accessories 37. . . . . . . . . . . . . . . . . . . . . . . .

Table 10: Accessory Power Cords 38. . . . . . . . . . . . . . . . . . . . .

PS2520, PS2520G, PS2521 & PS2521G User Manual

General Safety Summary

Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it.

Only qualified personnel should perform service procedures.

Injury Precautions

Use Proper Power Cord

T o avoid fire hazard, use only the power cord specified for this product.

Avoid Electric Overload

T o avoid electric shock or fire hazard, do not apply a voltage to a terminal that is outside the range specified for that terminal.

Ground the Product

This product is grounded through the grounding conductor of the power cord. T o avoid electric shock, the grounding conductor must be connected to earth ground. Before making connections to the input or output terminals of the product, ensure that the product is properly grounded.

Do Not Operate Without Covers

T o avoid electric shock or fire hazard, do not operate this product with covers or panels removed.

Use Proper Fuse

T o avoid fire hazard, use only the fuse type and rating specified for this product.

PS2520, PS2520G, PS2521 & PS2521G User Manual

iii

General Safety Summary

Do Not Operate in Wet/Damp Conditions

T o avoid electric shock, do not operate this product in wet or damp conditions.

Do Not Operate in Explosive Atmosphere

T o avoid injury or fire hazard, do not operate this product in an explosive atmosphere.

Avoid Exposed Circuitry

T o avoid injury, remove jewelry such as rings, watches, and other metallic objects. Do not touch exposed connections and components when power is present.

Product Damage Precautions

Use Proper Power Source

Do not operate this product from a power source that applies more than the voltage specified.

Use Proper V oltage Setting

Before applying power, ensure that the line selector is in the proper position for the power source being used.

Provide Proper Ventilation

T o prevent product overheating, provide proper ventilation.

Do Not Operate With Suspected Failures

If you suspect there is damage to this product, have it inspected by qualified service personnel.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Safety Terms and Symbols

Terms in This Manual

These terms may appear in this manual:

WARNING. Warning statements identify conditions or practices that could result in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property.

Terms on the Product

These terms may appear on the product:

General Safety Summary

DANGER indicates an injury hazard immediately accessible as you read the marking.

WARNING indicates an injury hazard not immediately accessible as you read the marking.

CAUTION indicates a hazard to property including the product.

Symbols on the Product

The following symbols may appear on the product:

DANGER

High Voltage

Protective Ground

(Earth) T erminal

ATTENTION

Refer to

Manual

PS2520, PS2520G, PS2521 & PS2521G User Manual

Double

Insulated

General Safety Summary

Certifications and Compliances

CSA Certified Power Cords

CSA Certification includes the products and power cords appropriate for use in the North America power network. All other power cords supplied are approved for the country of use.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Preface

This manual provides installation and operating instructions for the PS2520, PS2520G, PS2521, and PS2521G Programmable Power Supplies. The manual is organized as follows:

H Getting Started lists the product features, and describes how to

H Operating Basics provides an overview of the front and rear

H The Appendices list product specifications and other reference

Refer to the PS2520G and PS2521G Programmer Manual (070-9197-XX) for information on how to set up and use the PS2520G and PS2521G Programmable Power Supplies over the IEEE-488 General Purpose Interface Bus (GPIB).

install the power supply.

panel and details each operating task step by step. This section

also provides a practical example of each control setting.

information.

PS2520, PS2520G, PS2521 & PS2521G User Manual

vii

Preface

viii

PS2520, PS2520G, PS2521 & PS2521G User Manual

Getting Started

This section describes the features of the PS2520, PS2520G, PS2521, and PS2521G Programmable Power Supplies.

Be sure to set up your power supply using the installation instructions at the end of this section.

Product Description

The PS2520, PS2520G, PS2521, and PS2521G are programmable DC power supplies. All four power supplies have the following features:

H Three outputs allow independent, series, or parallel operation H Automatic series or parallel tracking H Easy to set, push-button controls H Data entry using the keypad, up/down keys H Four-digit displays for both voltage and current H Overvoltage and overcurrent protection H Display readouts for memory, output, and error code display H Precision digital-to-analog converter for high resolution H High stability, low drift output H Memory storage and recall H Automatic sequencing with timer H Diagnostic self-test at power on

In addition, the PS2520G and PS2521G power supplies include a GPIB interface that allows you to program and operate the power supply from a remote location over the General Purpose Interface Bus (GPIB).

For a complete list of specifications, refer to Appendix A: Specifica- tions on page 27.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Getting Started

Installation

Use the following installation procedure to properly configure and turn on the power supply for the first time:

1. Check the line voltage setting on the rear panel. If the line

voltage setting does not match the line voltage of your area, change the line voltage setting as shown in Figure 1.

Pry open cover with

flat-blade screwdriver.

Figure 1: Changing the Line V oltage Setting

Remove cam drum,

rotate to correct

selection, and reinsert.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Getting Started

CAUTION. To avoid damaging the instrument, make sure the line voltage setting and fuse type match the line voltage of your area.

2. Identify the fuse and replace it if necessary with the type

specified in Appendix C: Replaceable Parts on page 37. See

Figure 2 to replace the fuse.

Reinsert drawer and

close cover.

Pull fuse drawer out and

replace fuse.

Figure 2: Replacing the Line Fuse

3. Place the power supply on a level surface. Leave at least 10 cm

(4 in) clearance around the cabinet for cooling.

4. Connect the power cord to the connector on the rear of the power

supply and plug the other end into a wall receptacle.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Getting Started

5. Turn the power on. The display indicators will flash briefly. The

voltage and current readouts show the output settings. You should also hear the cooling fan running whenever the power is on.

The power supply performs a diagnostic self test at power on. If the diagnostic self test detects a problem, the unit displays an error code number in the form “Err –xxx.” If you encounter an error code, refer to Troubleshooting on page 32.

General Procedure

Use the following general procedure to connect one or more of the power supply outputs to a load. This procedure allows you to use the power supply safely. More information about each step is in Operating Basics on page 5.

1. Turn the power supply off and remove any connections on the

outputs.

2. Turn the power supply on.

3. Select the output you want to configure. Refer to Selecting the

Output on page 7.

4. Set the protection levels for the selected output. Refer to Setting

the Protection Levels on page 8.

5. Set the voltage and current limit for the selected output. Refer to

Setting Voltage and Current Limits on page 9.

6. Repeat steps 3 through 5 for the remaining outputs.

7. Turn the power supply supply off.

8. Connect the output(s) to the load(s). Refer to Connecting the

Outputs on page 11.

9. Turn the power supply on.

10.Enable the outputs. Refer to Enabling the Outputs on page 20.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

This section describes how to use the front panel controls and how to make connections to the power supply.

Functional Overview

Figure 3 illustrates the front panel features of the PS2520, PS2520G, PS2521, and PS2521G Programmable Power Supplies.

Amperes

Memory

Power switch

Figure 3: Front Panel Features

readout

Output

connectors

Volts

readout

KeypadOutput

controls

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

Figure 4 illustrates the rear panel features.

Sense

selector

GPIB

interface

(PS2520G and PS2521G only)

Power output and sense

input connectors

Cooling

fan

Line voltage

setting

Fuse

access

Power

connector

Figure 4: Rear Panel Features

Making a Control Setting

The front-panel controls allow you to set or program the amount of voltage, current, and protection for each output. T o make a control setting you must press specific control buttons in the correct sequence. To enter a number, for example, you must select the function, enter the number, and then press return ( presents an entry sequence of this type in the following form:

Press (function) → (number) → (return

PS2520, PS2520G, PS2521 & PS2521G User Manual

). This manual

)

Operating Basics

Items that compose the sequence appear in order from left to right with arrows separating each item.

An example follows each sequence string to help reinforce your understanding. Examples look like this:

Example: Set the voltage to 2.34 volts.

VOLTS SET → 2.34 → (return

T o select functions that have nomenclature above the output control buttons, you must first press the SHIFT button (see Figure 5). The shift indicator appears and remains active until you enter the function.

Example: Reset the OVP.

SHIFT → OVP RESET

Figure 5: SHIFT control

Selecting the Output

You must select the output before you can set the voltage, current, and protection levels for that output.

Press SHIFT → OUT(n) to select the output. Example: Select Output 2.

)

SHIFT → OUT2 The output indicator for Output 2 lights, and you can set the output

levels.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

Setting the Protection Levels

The OVP (overvoltage protection) and OCP (overcurrent protection) settings protect against supplying excessive voltage or current to an output load. If voltage or current reaches the protection level setting, the power supply disables the outputs.

CAUTION. To prevent damaging a circuit under test, set protection levels before you apply power to the circuit.

Setting the OVP

The OVP (overvoltage protection) circuit automatically disables the output when the voltage on the output reaches the set level.

Press OVP SET → (number) → (return Example: Set the overvoltage protection for Output 1 to 6 volts:

1. SHIFT → OUT1

2. OVP SET → 6 → (return

Pressing the OVP SET again momentarily displays the OVP level and allows you to confirm the setting.

Resetting the OVP

Using the previous example, if the Output 1 voltage reaches 6 volts, the power supply automatically disables the output and displays the message “Err –013.”

T o reset the OVP, correct the condition causing the overvoltage and press SHIFT → OVP RESET

Setting the OCP

Pressing OCP automatically disable the outputs upon reaching the current limit. The OCP indicator appears on the display when the OCP is on.

ON (overcurrent protection on) sets the power supply to

)

) to enter the OVP level.

PS2520, PS2520G, PS2521 & PS2521G User Manual

When the OCP circuit disables the output, it displays the message “Err –012”. When this happens, correct the setup and remove the error message by toggling OCP off and then on again.

When the OCP is not on, the power supply still limits the current to the set level and reduces the voltage as necessary to control the power. Refer to the following section for instructions on how to set the current limit.

Setting Voltage and Current Limits

The power supplies provide either constant voltage or constant current to a load. The voltage limit, current limit, and the size of the load connected to the output determines whether the power supply holds the voltage constant or the current constant. The appropriate indicator appears on the display to indicate whether constant voltage (C.V.) or constant current (C.C.) is active.

Using the Keypad to Set Limits

Operating Basics

Press VOLTS SET → (number) → (return limit.

Press CURRENT SET → (number) → (return current limit.

Example: Set the voltage of Output 3 to 4.2 volts with a maximum current of 0.3 amperes.

1. Select Output 3:

SHIFT → OUT3

2. Set the voltage level of the output to 4.2 V:

VOLTS SET → 4.2 → (return

3. Set the current limit of the output to 0.3 A:

CURRENT SET → .3 → (return

The power supply keeps the voltage constant if the load does not require more than 0.3 amperes. The power supply indicates C.V. on the display.

PS2520, PS2520G, PS2521 & PS2521G User Manual

)

) to enter the voltage

) to enter the

Operating Basics

Once the load tries to draw more than 0.3 amperes, however, the supply holds the current to 0.3 amperes (unless OCP is on) and allows the voltage level to vary accordingly. The power supply then indicates C.C. on the display.

Setting Voltage and Current Steps

The CURRENT and VOL TS keys allow you to make minor adjustments to the current and voltage settings.

The STEP SET function determines the amount that the arrow keys increment or decrement the setting when you press them.

Press STEP SET → VOLTS SET → (number) → (return the amount of each voltage step increment and decrement.

Press STEP SET → CURRENT SET → (number) → (return set the amount of each current step increment and decrement.

NOTE. The power supplies permit voltage steps up to 2.000 V and current steps up to 0.200 A.

Example: Set voltage steps to 0.5 V and current steps to 0.1 A.

1. Set voltage steps to 0.5 V:

STEP SET → VOLTS SET → .5 → (return

2. Set current steps to 0.1 A:

STEP SET → CURRENT SET → .1 → (return

Press VOLTS voltage limit by steps of 0.5 V.

to increase (and press VOLTS to decrease) the

(step up) and (step down) arrow

) to set

) to

)

Press CURRENT decrease) the current limit by steps of 0.1 A.

Press and hold the arrow key to increase the selection speed.

to increase (and press CURRENT to

PS2520, PS2520G, PS2521 & PS2521G User Manual

Connecting the Outputs

After setting the voltage and current limits, turn the power off and connect the outputs to one or more loads. The binding posts on the front outputs accept wires, spade lugs, or banana plugs. The rear output terminals provide additional output connections. You can make connections with or without reference to ground to each supply independently, in series or in parallel.

WARNING. To avoid electrical shock and damage to circuits connected to the outputs, make sure that you turn the power supply off before making or changing output connections.

Referencing Outputs to Ground

There are two types of power supply connections in relation to ground: isolated ground or ground referenced. Figure 6 shows both types of connections.

Operating Basics

Voltage Voltage Voltage

Isolated ground Ground referenced

Figure 6: Isolated-Ground Connection

Use an isolated-ground connection when it is unnecessary or undesirable to connect one of the outputs to ground.

T o reference an output connection to ground, do one of the following:

H Connect the positive output to the ground terminal to supply a

negative voltage across the load.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

H Connect the negative output to the ground terminal to supply a

positive voltage across the load.

NOTE. The ground post on the power supply internally connects to earth ground through the power supply chassis and line cord.

Independent Operation

Independent operation allows you connect each of the three outputs to separate loads or to connect the outputs in series or in parallel with external connections. When the outputs are in the independent mode of operation, the SERIES and PARA indicators are not lighted. See Figure 7 for examples of independent output connections.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Isolated-gro

und connec

tions

Operating Basics

OUTPUT 1 OUTPUT 2

–+

GND

–+

Load 1

Negative-ground connections

OUTPUT 1 OUTPUT 2

–+

GND

–+

Load 1

Positive-ground and negative-ground connections

OUTPUT 1 OUTPUT 2

–+

–V

GND

–+

Load 1

Load 2

OUTPUT 3

–+

Load 3

OUTPUT 3

–+

Load 3

OUTPUT 3

–+

–V

Load 3

Figure 7: Examples of Independent Output Connections

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

External Series Connections. To achieve a potential across the load that exceeds the output of a single power supply, connect two or more power supplies in series. Figure 8 illustrates two independent power supplies connected in series. Note that the voltages of the power supplies add together but the currents do not.

20 V, 1 A 15 V, 1 A

–+–+

Figure 8: Connecting Power Supplies in Series

WARNING. Voltages more than 60 VDC are a lethal shock hazard to the user. Be careful when connecting power supplies in series to achieve voltages higher than 60 VDC total or 60 VDC between any connection and earth ground.

35 V, 1 A



Refer to Figure 9 for examples of different types of series connections using the three outputs.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Isolated-gro

und

Operating Basics

OUTPUT 1 OUTPUT 2

–+

GND

Total

Negative-ground

OUTPUT 1 OUTPUT 2

–+

GND

Positive-ground

OUTPUT 1 OUTPUT 2

–+

GND

= –(V1 + V2 + V3)

T otal

–+

= V1 = V2 + V

Load

–+

= V2 + V

T otal

Load

–+

Load

OUTPUT 3

–+

OUTPUT 3

–+

OUTPUT 3

–+

Figure 9: Examples of External Series Connections

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

External Parallel Connections. To supply more current than any one supply can provide individually, connect two or more power supplies in parallel. Figure 10 illustrates two power supplies externally connected in parallel. Note that the currents add together but the voltages do not. For this example the power supplies are set to independent and the SERIES and PARA indicators are not lighted.

20 V, 1 A 20 V, 1 A

–+–+

Figure 10: Connecting Power Supplies in Parallel

20 V, 2 A



CAUTION. To avoid damaging the output circuitry of the power supply, do not apply a voltage across an output that exceeds the voltage rating of that output.

Refer to Figure 11 for examples of different types of parallel connections using the three outputs.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Isolated-ground

Operating Basics

OUTPUT 1 OUTPUT 2

–+



GND

Negative-ground

OUTPUT 1 OUTPUT 2

–+

GND

Positive-ground

OUTPUT 1 OUTPUT 2

–+

GND

–+

 I

I

Load

Maximum

= I

1Max

–+

 I

I

Maximum

Load

–+

OUTPUT 3 –+



+ I

2Max

3Max

OUTPUT 3

–+



= I

+ I

2Max

3Max

OUTPUT 3

–+



Load

 I

I

Maximum

= I

1Max

Figure 11: Examples of External Parallel Connections

PS2520, PS2520G, PS2521 & PS2521G User Manual

+ I

2Max

+ I

3Max



Operating Basics

Master/Slave Operation

The SERIES and PARA controls on the front panel allow you to internally connect Output 1 and Output 2 in series or parallel. When you do this, Output 2 (the master output) sets Output 1 (the slave output) to the same level as the Output 2 setting. These modes of operation are also called series tracking and parallel tracking.

Output 3 is always independent. You can connect Output 3 in series or parallel with the other outputs by using external connections only.

T able 1 shows the maximum output available for the power supplies in SERIES and PARA operation

Table 1: Maximum Output in Series and Para Modes

Model

PS2520, PS2520G 40 V, 2.5 A 20 V, 5 A PS2521, PS2521G 72 V, 1.5 A 36 V, 3 A

Series Para

Series Tracking. Select SERIES to internally connect Output 1 and

Output 2 in series. Output 2 is the master.

Press SHIFT → SERIES The SERIES indicator lights. Use the Output 2 settings to control the power to the load. The

Output 2 voltage setting should be one half of the total output voltage desired. (The voltage across Output 1 and Output 2 in series is twice that of Output 2.) The current setting for Output 2 controls the maximum current available to the load. See Figure 12.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

–+

Slave

GND

–+–+

Master

Internal connection

Total

= V

Master

I

× 2

Maximum

= I

Master

Figure 12: Series-Tracking Operation

Parallel Tracking. Select PARA to internally connect Output 1 and

Output 2 in parallel. Output 2 is the master.

Press SHIFT → PARA The PARA indicator lights. Use the Output 2 settings to control the power to the load. The

voltage across Output 1 and Output 2 in parallel is the same as the Output 2 setting. The current available from Output 1 and Output 2 in parallel is twice that of the Output 2 setting. See Figure 13.

–+

Slave

GND

–+–+

Master

Internal connection

= V

Total

Master

I

Maximum

= I

Master

× 2

Figure 13: Parallel-Tracking Operation

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

Enabling the Outputs

Press the OUTPUT ON/OFF button (Figure 14) to enable the power to all outputs.

Press to enable power to the outputs.

Figure 14: Output On/Off Button

The OUT indicator appears and all outputs are active. Press the OUTPUT

remove power from the load or loads connected to the output terminals.

ON/OFF button again to disable the outputs and

Sensing the Output Level

Although the front and rear output terminals simultaneously supply power, the power supply senses the voltage level internally from either the front or rear terminals. Use the SENSE selector located on the rear panel to select the appropriate sense input. See Figure 15.

As the length of the output leads or the amount of output current increases, the amount of voltage drop across the output leads also increases. In this case, the internal sense connection does not accurately measure the voltage across the load. T o compensate for

PS2520, PS2520G, PS2521 & PS2521G User Manual

this problem the power supply has auxiliary sense inputs on the rear panel. Using these inputs, as illustrated in Figure 15, bypasses the voltage dropped across the output leads and senses the voltage directly across the load. It is best to use a shielded two-wire cable for this connection to prevent extraneous noise from affecting the sense measurement.

Remove shorting bars.

Load

Connect sense inputs across load.

Figure 15: Connecting the Auxiliary Sense Inputs

Operating Basics

Storing and Recalling Settings

The power supplies allow you to store voltage and current settings in as many as 50 different memory locations (00 – 49). Each location stores the settings for all three outputs. You can recall the settings of any location individually or you can step through the settings for each memory location in sequence.

Storing a Setting

The Store function saves the front panel settings for OVP, voltage limit, current limit, and delay timer in a specific memory location. (The section that describes the delay timer operation begins on page 24.)

Press SHIFT → STORE → (memory location number) →

(return

PS2520, PS2520G, PS2521 & PS2521G User Manual

) to store the settings in memory.

Operating Basics

Example: Store the power supply settings for all three outputs in memory location 01:

SHIFT → STORE → 1 → (return )

Recalling an Individual Setting

The Recall function recalls the settings stored in a specific memory location.

Press SHIFT → RECALL → (memory location number) →

(return

Example: Recall the settings for all three outputs from memory location 01:

) to recall a particular setting from memory.

SHIFT → RECALL → 1 → (return

Storing and Recalling a Sequence of Settings

T o create an automatic test routine, you can program the power supply to sequence through the settings stored in two or more consecutive memory locations. You can recall the sequence of stored settings either manually or automatically.

Manual Sequencing. Manual sequencing allows you to step through the stored settings one at a time by pressing the RECALL NEXT or RECALL LAST buttons.

1. Press SHIFT → STORE → (memory location number) →

(return consecutive memory location for each setting.

2. Press SHIFT → RECALL → (first memory location) → (decimal point) → (last memory location) → (return specify the first through last memory locations in the sequence.

3. Press RECALL NEXT to recall the next memory location in the sequence. Press RECALL LAST to recall the previous memory location in the sequence.

) to store a setting. Repeat for each new setting, using a

)

) to

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

Example: Store three new settings for Output 1 and manually recall the settings in sequence:

H Store 1 V, 0.1 A in memory location 01. H Store 2 V, 0.15 A in memory location 02. H Store 3 V, 0.15 A in memory location 03. H Recall the settings of each memory location in order (01 – 03).

1. Select Output 1:

SHIFT → OUT1

2. Set the voltage limit to 1 V and the current limit to 0.1 A:

VOLTS SET → 1 → (return CURRENT SET → .1 → (return

3. Store this setting in memory location 01:

SHIFT → STORE → 1 → (return

4. Set the voltage limit to 2 V and the current limit to 0.15 A:

VOLTS SET → 2 → (return CURRENT SET → .15 → (return

5. Store this setting in memory location 02:

SHIFT → STORE → 2 → (return

6. Store 3 V, 0.15 A in memory location 03:

VOLTS SET → 3 → (return SHIFT → STORE → 3 → (return

Note the current limit setting for location 03 is the same as location 02; therefore, you do not have to re-enter the current limit setting.

7. Set the sequence for memory locations 01 through 03:

SHIFT → RECALL → 1.3 → (return

)

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

8. Recall the settings in memory locations 01, 02, and 03 in that order:

SHIFT → RECALL → 1 → (return

)

RECALL NEXT → RECALL NEXT

Pressing RECALL NEXT recalls the next memory location in the sequence. (RECALL LAST recalls the previous memory location.)

Automatic Sequencing. To automatically output a sequence of stored settings, you must store the delay time along with the other settings for each memory location. The minimum delay time setting is 1 second; the maximum is 65535 seconds.

1. Press DELAY → (seconds) → (return

) to specify the delay

time for a sequence step.

2. Press SHIFT → STORE → (memory location number) → (return

) to store a setting.

3. Repeat steps 1 and 2 for each new setting, using a consecutive memory location for each setting.

4. Press SHIFT → RECALL → (first memory location) → (decimal point) → (last memory location) → (return

) to

specify the first through last memory locations in the sequence.

5. Press AUTO SEQ

ON → OUTPUT ON to automatically output

the settings in sequence. Example: Recall the previously stored memory locations 01 and

02 and set the delay times for each as follows: 01: 3 seconds 02: 7 seconds Set the test loop for memory locations 01 and 02.

1. Recall the settings in memory location 01: SHIFT → RECALL → 1 → (return

2. Set the delay time to 3 seconds: DELAY → 3 → (return

)

PS2520, PS2520G, PS2521 & PS2521G User Manual

)

3. Store this setting back into memory location 01:

Operating Basics

SHIFT → STORE → 1 → (return

4. Recall the settings in memory location 02:

SHIFT → RECALL → 2 → (return

5. Set the delay time for memory location 02:

DELAY → 7 → (return

6. Store this setting back into memory location 02:

SHIFT → STORE → 2 → (return

7. Specify the sequence to contain only locations 01 through 02:

SHIFT → RECALL → 1.2 → (return

8. Set the power supply to automatically output and repeat this

sequence starting with memory location 01:

AUTO SEQ

The AUTO and OUT indicators appear and the sequence starts running.

ON → OUTPUT ON

Setting the GPIB Address

If you have a PS2520G or PS2521G Programmable Power Supply, use the ADDRESS/LOCAL control to set or read the GPIB address of the power supply. Refer to the PS2520G and PS2521G Program- mer Manual for more details.

)

PS2520, PS2520G, PS2521 & PS2521G User Manual

Operating Basics

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix A: Specifications

T ables 2 through 5 list the specifications of the PS2520, PS2520G, PS2521, and PS2521G Programmable Power Supplies.

Table 2: Operating Characteristics

Name

Independent Output Ratings

Series Tracking Output Rating

Parallel Tracking Output Rating

Maximum OVP PS2520 and PS2520G:

Load Effect Voltage: ≤ 3 mV, rear output; ≤ 6 mV, front output

Source Effect Voltage: ≤ 3 mV

Resolution Voltage: 10 mV (20 mV if rating voltage  36 V)

Characteristic

PS2520 and PS2520G: two outputs 0 to 36 V, 0 to 1.5 A and one output 0 to 6 V, 3 A

PS2521 and PS2521G: two outputs 0 to 20 V, 0 to 2.5 A one output 0 to 6 V, 0 to 5 A

PS2520 and PS2520G: 0 to 72 V, 0 to 1.5 A PS2521 and PS2521G: 0 to 40 V, 0 to 2.5 A

PS2520 and PS2520G: 0 to 36 V, 0 to 3 A PS2521 and PS2521G: 0 to 20 V, 0 to 5 A

38.5 V on 36 V outputs

7.0 V on 6 V output PS2521 and PS2521G:

22.5 V on 20 V outputs

7.0 V on 6 V output

Current: ≤ 3 mA (≤ 6 mA if rating current  3.5 A)

Current: ≤ 3 mA

Current: 1 mA (2 mA if rating current  3.5 A) OVP: 10 mV (20 mV if rating voltage  36 V)

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix A: Specifications

Table 2: Operating Characteristics (Cont.)

Name Characteristic

Program Accuracy (25 ± 5_ C)

Ripple and Noise 20 Hz to 20 MHz

Temperature Coefficient (0_ C to 40_ C)

Readback Resolution

Readback Accuracy (25 ± 5_ C)

Voltage: ≤ 0.05% + 25 mV (+50 mV if rating voltage  36 V)

Current: ≤ 0.2% + 10 mA OVP: ≤ 2% + 0.6 V

Voltage Ripple: 1 mV Voltage Noise: 2 mV Current: ≤ 3 mA

RMS

/3 mV

RMS

/30 mV

RMS

(≤ 5 mA

p-p

if rating current 

RMS

3.5 A) Voltage: ≤ 100 ppm + 3 mV

Current: ≤ 150 ppm + 3 mA Voltage: 10 mV (20 mV if rating voltage  36 V)

Current: 1 mA (2 mA if rating current  3.5 A) Voltage: ≤ 0.05% + 25 mV (+50 mV if rating voltage

 36 V)

Current: ≤ 0.2% + 10 mA

Response Time 10% to 90% (up): ≤ 100 ms

90% to 10% (down): ≤ 100 ms (≥ 10% rating load)

Readback Temperature Coefficient

Voltage: ≤ 100 ppm + 10 mV (+20 mV if rating voltage  36 V)

Current: ≤ 150 ppm + 10 mA

Drift

Voltage: ≤ 0.03% + 6 mV Current: ≤ 0.1% + 6 mA

Series Tracking

tracking error load effect source effect

Voltage: ≤ 0.1% + 50 mV Voltage: ≤ 50 mV Voltage: ≤ 3 mV

PS2520, PS2520G, PS2521 & PS2521G User Manual

Table 2: Operating Characteristics (Cont.)

Name Characteristic

Parallel Tracking

Appendix A: Specifications

program accuracy (25 ± 5_ C)

load effect

source effect

GPIB Capability IEEE-488.2 (optional)

Memory Locations (Store and Recall)

Timer Setting Time: 1 to 65535 seconds

Change in output over an 8-hour interval under constant line, load, and ambient temperature following a 30-minute warmup.

Voltage: ≤ 0.05% + 25 mV (+50 mV if rating voltage > 36 V)

Current:: ≤ 0.2% + 20 mA OVP: ≤ 2% + 0.6 V

Voltage: ≤ 3 mV rear output (≤ 6 mV front output) Current: ≤ 6 mA (≤ 12 mA if rating current > 3.5 A) Voltage: ≤ 3 mV Current: ≤ 6 mA

SH1, AH1, T6, L4, SR1, RL1, PP0, DC1, DT0, C0, E1

00 – 49 (50 locations)

Resolution: 1 second

Table 3: Electrical Characteristics

Name Description

Power Source 100, 120, and 220 VAC, ± 10% 50 – 60 Hz

240 VAC –10% + 4.2% 50 – 60 Hz

Safety ETL listed to UL 1244

Certified to CSA–C22.2 No 231–M89

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix A: Specifications

Table 4: Environmental Characteristics

Name

Storage Temperature Operating Temperature

Description

–10_ C to +70_ C (+14_ F to +158_ F) 0_ C to +40_ C (+32_ F to +104_ F)

Table 5: Physical Characteristics

Name

Overall Dimensions Width: 255 mm (10.0 in)

Weight 10 kg (22 lbs)

Description

Height: 145 mm (5.7 in) Depth: 346 mm (13.6 in)

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix B: Maintenance

This appendix provides information for the basic maintenance of the power supply . Electronic maintenance on the power supply must be performed by a trained technician. However, an operator can perform some basic and routine maintenance.

Cleaning

T o clean the power supply, use a soft cloth dampened in a solution of mild detergent and water. Do not spray cleaner directly onto the instrument, since it may leak into the cabinet and cause damage.

Do not use chemicals containing benzine, benzene, toluene, xylene, acetone, or similar solvents.

Do not use abrasive cleaners on any portion of the frequency counter.

Warranty Service

The power supplies are covered by a standard T ektronix one-year warranty . The warranty statement appears at the front of this manual. If the power supply fails during the warranty period, return it to T ektronix for free servicing (subject to conditions of the warranty statement).

T o arrange for warranty service or to get an estimate on a product that is out of warranty, call your local Tektronix office. If you are within the continental U.S., you may call 1-800-TEK-WIDE (1-800-835-9433) for assistance. When you call, have the serial number of the power supply available. The serial number is located on the left side of the rear panel.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix B: Maintenance

Repackaging for Shipment

If your instrument must be returned for servicing, use the original packing materials if possible. If the original materials are unfit or unavailable, repackage the power supply in the following manner:

1. Use a sturdy shipping carton made of corrugated cardboard that has an interior size of at least 15 cm (6 in) greater than the instrument size in all directions.

2. Enclose the following information:

H Owner’s name and address H Name and phone number of a person that T ektronix should

contact

H Serial number of the instrument H Description of the problem

3. Completely wrap the power supply with polyethylene sheeting (or equivalent material) to protect the outside finish and keep harmful substances out of the power supply.

4. Cushion the instrument on all sides with 8 cm (3 in) of padding material or urethane foam tightly packed between the carton and the instrument.

5. Seal the shipping carton with an industrial stapler or strapping tape.

6. Call your local Tektronix office for shipping instructions. If you are within the continental U.S., you may call 1-800-TEK-WIDE (1-800-835–9433) for assistance.

Troubleshooting

If the power supply does not function properly, refer to Table 6 to eliminate operating faults.

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix B: Maintenance

WARNING. To prevent electrical shock, unplug the power cord and disconnect the outputs before changing the line fuse or line voltage setting.

Table 6: Troubleshooting Steps

Symptom

Supply does not power on H Power cord not connected properly; check

No output or incorrect output

Error Message (“Err...”) H Setup error; check error number against error

Possible Causes

connections.

H Line voltage selection not correct; check

setting.

H Fuse blown; disconnect line cord and see

page 2 to open cover and replace fuse. Use the proper fuse for the line voltage setting. See page 37 for fuse part numbers.

H Leads not properly connected to the positive

and negative outputs.

H The output is not enabled (“OUT” indicator is

not lighted); press the OUTPUT button.

H The power supply settings are not appropriate

for the output load. The power supply is functioning normally by limiting either current or voltage. Check load or disconnect output to verify.

description in Table 7 on page 34.

H Overvoltage protection tripped; correct the

cause and clear error (OVP RESET). Set overvoltage protection to a higher value if necessary.

H Overcurrent protection tripped; correct the

cause and clear the error (OCP

The power supply indicates an error in setup or operation by displaying the message “Err –xxx” on the front panel. T able 7 lists each message number and explains what the error code means.

PS2520, PS2520G, PS2521 & PS2521G User Manual

OFF).

Appendix B: Maintenance

Table 7: Error Messages

Front Panel Error Code

0 “No error” –001 “Self-test failed; CPU test error” –002 “Self-test failed; RAM test error” –003 “Self-test failed; ROM test error”

–005 “Self-test failed; DAC/ADC test error”

–012 “Device-specific error; Overcurrent protection error” –013 “Device-specific error; Overvoltage protection error”

–016 “Data out of range; Voltage too large” –017 “Data out of range; Current too large” –018 “Data out of range; Voltage too small” –019 “Data out of range; Current too small”

Description

–064 “Setting conflict; Timer setting error” –065 “Setting conflict; Overvoltage protection setting error” –066 “Setting conflict; Address setting error” –067 “Setting conflict; Voltage setting error” –068 “Setting conflict; Current setting error” –069 “Setting conflict; Recall setting error” –070 “Setting conflict; Store setting error”

–091 “Device-specific error; Calibration current full-scale error” –092 “Device-specific error; Calibration voltage full-scale error”

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix B: Maintenance

Table 7: Error Messages (Cont.)

Front Panel Error Code

–093 “Device-specific error; Calibration overvoltage protection

–094 “Device-specific error; Calibration overvoltage protection

Description

full-scale error”

offset error”

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix B: Maintenance

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix C: Replaceable Parts

Replaceable parts may be ordered directly from your authorized T ektronix dealer.

Standard Accessories

The items listed in T able 8 are shipped with the power supply:

Table 8: Standard Accessories

Accessory

Fuse,3AG, 4A, 250V,SB (90 – 132 V operation)

User Manual 070-9196-XX Programmer Manual (PS2520G and

PS2521G only) Three sets of test leads 196-3384-XX 115V Power Cord Refer to Table 10

Optional Accessories

The items listed in T able 9 are available as optional accessories:

Table 9: Optional Accessories

Accessory

Fuse,3AG, 2A, 250V,SB (198 – 250 V operation)

230V Power Cords Refer to Table 10

Tektronix Part Number

159-0149-00

070-9197-XX

Tektronix Part Number

159–0023–00

PS2520, PS2520G, PS2521 & PS2521G User Manual

Appendix C: Replaceable Parts

The following power cords are available.

Table 10: Accessory Power Cords

Plug Configuration

Normal Usage

North America 115 V

Tektronix Part Number

161-0104-00

Europe 230 V

United Kingdom 230 V

Australia 230 V

North America 230 V

Switzerland 230 V

161-0104-06

161-0104-07

161-0104-05

161-0104-08

161-0167-00

PS2520, PS2520G, PS2521 & PS2521G User Manual

Index

accessories

optional, 37

standard, 37 amperes readout, depicted, 5 automatic tracking, 18

C.C., definition of, 9 C.V., definition of, 9 characteristics

electrical, 29

environmental, 30

operating, 27

physical, 30 cleaning, 31 connection

external parallel, 16

external series, 14

ground referenced, 11

isolated ground, 11

parallel, depicted, 16 controls

Tektronix PS2520, PS2521, PS2520G, PS2521G User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

User Manual

Table of Contents

List of Figures

List of Tables

General Safety Summary

Injury Precautions

Product Damage Precautions

Safety Terms and Symbols

Certifications and Compliances

Preface

Getting Started

Product Description

Installation

General Procedure

Operating Basics

Functional Overview

Making a Control Setting

Selecting the Output

Setting the Protection Levels

Setting Voltage and Current Limits

Connecting the Outputs

Enabling the Outputs

Sensing the Output Level

Storing and Recalling Settings

Setting the GPIB Address

Appendix A: Specifications

Appendix B: Maintenance

Cleaning

Warranty Service

Repackaging for Shipment

Troubleshooting

Appendix C: Replaceable Parts

Standard Accessories

Optional Accessories

Index