Agilent Technologies E3617A, E3614A, E3615A, E3616A User Manual



Agilent E361xA 60W BENCH SERIES DC POWER SUPPLIES

OPERATING AND SERVICE MANUAL FOR MODELS:

Agilent E3614A
Agilent E3615A

Manual Part No. 5959-5310

Agilent E3616A
Agilent E3617A

April 2000

Edition 8

1-1

SAFETY SUMMARY

The following general safety precautions must be observed during all phases of operation, service, and repair of this instrument.
Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design,
manufacture, and intended use of the instrument. Agilent Technologies assumes no liability for the customer's failure to comply
with these requirements.

BEFORE APPLYING POWER.

Verify that the product is set to match the available line voltage
and that the correct fuse is installed.

GROUND THE INSTRUMENT.

This product is a Safety Class I instrument (provided with a pro­tective earth terminal). To minimize shock hazard, the instrument
chassis and cabinet must be connected to an electrical ground.
The instrument must be connected to the ac power supply mains
through a three-conductor power cable, with the third wire firmly
connected to an electrical ground(safety ground) at the power
outlet. Any interruption of the protective(grounding) conductor or
disconnection of the protective earth terminal will cause a poten­tial shock hazard that could result in personal injury. If the instru­ment is to be energized via an external autotransformer for
voltage reduction, be certain that the autotransformer common
terminal is connected to the neutral(earthed pole) of the ac power
lines (supply mains).

DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE.

Do not operate the instrument in the presence of flammable
gases or fumes.

KEEP AWAY FROM LIVE CIRCUITS.

Operating personnel must not remove instrument covers. Compo­nent replacement and internal adjustments must be made by
qualified service personnel. Do not replace components with
power cable connected. Under certain conditions, dangerous volt­ages may exist even with the power cable removed. To avoid inju­ries, always disconnect power, discharge circuits and remove
external voltage sources before touching components.

DO NOT SERVICE OR ADJUST ALONE.

Do not attempt internal service or adjustment unless another per­son, capable of rendering first aid and resuscitation, is present.

SAFETY SYMBOLS

Instruction manual symbol; the product will
be marked with this symbol when it is neces-

!

or

WARNING

CAUTION

NOTE

DO NOT SUBSTITUTE PARTS OR MODIFY INSTRUMENT.

Because of the danger of introducing additional hazards, do not
install substitute parts or perform any unauthorized modification
to the instrument. Return the instrument to a Agilent Technologies
Sales and Service Office for service and repair to ensure that
safety features are maintained.

sary for the user to refer to the instruction
manual.

Indicate earth(ground) terminal.

The WARNING sign denotes a hazard. It
calls attention to a procedure, practice,
or the like, which, if not correctly performed or
adhered to, could result inpersonal injury. Do
not proceed beyond a WARNING sign until
the indicated conditions are fully understood
and met.

The CAUTION sign denotes a hazard. It calls
attention to an operating procedure, or the
like, which, if not correctly performed or
adhered to, could result in damage to or
destruction of part or all of the product. Do
not proceed beyond CAUTION sign until the
indicated conditions are fully understood and
met.

The NOTE sign denotes important infor­mation. It calls attention to a procedure, prac­tice, condition or the like, which is essential to
highlight.

Instruments that appear damaged or defective should be made inoperative and secured against unintended
operation until they can be repaired by qualified service personnel.

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Table of Contents

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SAFETY SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2

GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

SAFETY REQUIREMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

INSTRUMENT AND MANUAL IDENTIFICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

OPTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

ACCESSORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5

INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

INITIAL INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

Mechanical Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

Electrical Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

INSTALLATION DATA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

Location and Coolin
Outline Dia
Rack Mountin

INPUT POWER REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

Line Volta

Power Cord. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7

ram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

e Option Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

OPERATING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7

TURN-ON CHECKOUT PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7

OPERATING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

LOCAL OPERATING MODE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

Constant Volta

Constant Current Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

Overvolta

CONNECTING LOADS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

OPERATION BEYOND RATED OUTPUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

REMOTE OPERATING MODES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9

Remote Volta

Remote Analo

e Operaton. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

e Protection (OVP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

e Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9

Voltage Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9

MULTIPLE-SUPPLY OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10

NORMAL PARALLEL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10

AUTO-PARALLEL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10

NORMAL SERIES OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11

AUTO-SERIES OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-12

AUTO-TRACKING OPERATON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-13

LOAD CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14

PULSE LOADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14

REVERSE CURRENT LOADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14

OUTPUT CAPACITANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

REVERSE VOLTAGE LOADING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14

BATTERY CHARGING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-14

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GENERAL INFORMATION

INTRODUCTION

This manual describes all models in the Agilent E361xA 60W
Bench Power Supply family and unless stated otherwise, the
information in this manual applies to all models.

SAFETY REQUIREMENTS

This product is a Safety Class I instrument, which means
that it is provided with a protective earth ground terminal.
This terminal must be connected to an ac source that has a
3-wire ground receptacle. Review the instrument rear panel
and this manual for safety markings and instructions before
operating the instrument. Refer to the Safety Summary page
at the beginning of this manual for a summary of general
safety information. Specif ic safety information is located at
the appropriate places in this manual.

This power supply is designed to comply with the following
safety and EMC(Electromagnetic Compatibility) requirements

n

IEC 348: Safety Requirements for Electronic Measuring

Apparatus

n

IEC 1010-1/EN 61010: Safety Requirements for Electrical

Equipment for Measurement, Control, and Laboratory Use

n

CSA C22.2 No.231: Safety Requirements for Electrical and

Electronic Measuring and Test Equipment

n

UL 1244: Electrical and Electronic Measuring and Testing

Equipment.

n

EMC Directive 89/336/EEC: Council Directive entitled
Approximation of the Laws of the Member States relating to
Electromagnetic Compatibility

n

EN 55011(1991) Group 1, Class B/CISPR 11: Limits and

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Methods of Radio Interference Characteristics of

n

Industrial, Scientific, and Medical(ISM) Radio-Frequency
Equipment

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EN 50082-1(1991) /

IEC 801-2(1991):Electrostatic Discharge Requirements
IEC 801-3(1984):Radiated Electromagnetic Field

Requirements

IEC 801-4(1988):Electrical Fast Transient/Burst

Requirements

n

ICES/NMB-001

This ISM device complies with Canadian ICES-001.

Cet appareil ISM est conforme à la norme NMB-001 du Can-

ada.

INSTRUMENT AND MANU AL ID ENTIFI CATION

A serial number identifies your power supply. The serial
number encodes the country of manufacture, the date of the
latest significant design change, and a unique sequential
number. As an illustration, a serial number beginning with
KR306 denotes a power supply built in 1993 (3=1 993,
4=1994, etc), 6th week manufacture in Korea(KR). The
remaining digits of the serial number are a unique, five-digit
number assigned sequentially.

If a yellow Change Sheet is supplied with this manual, its pur­pose is to explain any differences between your instrument
and the instrument described in this manual. The change
sheet may also contain information for correcting errors in
the manual.

OPTIONS

Options 0EM, 0E3 and 0E9 determine which line voltage is
selected at the factory. The st andard unit is configured for 115
Vac ± 10%. For information about changing the line voltage
setting, see paragraph "INPUT POWER REQUIREMENTS",
page 1-6.

0EM: Input power, 115 Vac ± 10%, 47-63 Hz
0E3: Input power, 230 Vac ± 10%, 47-63 Hz
0E9: Input power, 100 Vac ± 10%, 47-63 Hz
0L2: One additional manual

ACCESSORY

The accessory listed below may be ordered from your local
Agilent Technologies Sales Office either with the power sup­ply or separately . (Refer to the li st at the rear of t he manual for
address.)

Agilent Part No.Description

5063-9240 Rack Kit for mounting one or two 3 1/2" high

supply in a standard 19" rack

The rack mount kit is needed for rack mounting of all models
in the Agilent E361xA power supply because these supplies
have molded feet.

DESCRIPTION

This power supply is suitable for either bench or rack
mounted operation. It is a compact, well-regulated, Constant
Voltage/Constant Current supply that will furnish full rated
output voltage at the maximum rated output current or can be
continuously adjusted throughout the output range. The out­put can be adjusted both locally from the front panel and
remotely by changing the settings of the rear panel switches
(See paragraph "REMOTE OPERATING MODES", page 1-9).
The models in this family offer up to 60 watts of output power,
with voltage up to 60 volts and current up to 6 amps as shown
in Table 1.

The front panel VOLTAGE control can be used to establish
the voltage limit when the supply is used as a constant cur­rent source and the CURRENT control can be used to estab­lish the output current limit when the supply is used as a
constant voltage source. The supply will automatically cross
over from constant voltage to constant current operation and
vice versa if the output current or voltage exceeds these pre­set limits.

The front panel includes an autoranging (E3614A single­range) digital voltmeter and a single-range digital ammeter.
Two 3 1/2 digit voltage and current displays accurately show
the output voltage and current respectively. The output rat­ings for each model are shown in the Specifications and
Operating Characteristics Table.

The OVP/CC SET switch is used to check the OVP trip volt­age and current control set value. When pressing this switch,
the voltage display indicates the OVP trip voltage and the cur­rent display indicates the current control set value.

The power supply has both front and rear output terminals.
Either the positive or negative output terminal may be

1-4

be grounded or the power supply can be operated float­ing at up to a maximum of 240 Volts off ground. Total out­put voltage to ground must not exceed 240 Vdc.

LINE FUSE

Line Voltage Fuse Agilent Part No.
100/115 Vac 2.0 AT 2110-0702
230 Vac 1.0 AT 2110-0457

Table 1. Specifications and Operating Characteristics

SPECIFICATIONS

Detailed specifications for the power supply are given in Table

1. All specifications are at front terminals with a resistive load,
and local sensing unless otherwise stated. Operating charac­teristics provide useful, but non-warranted information in the
form of the nominal performance.

*AC INPUT

An internal switch permits operation from 100, 115, or 230 Vac
lines.

100 Vac ± 10%, 47-63 Hz, 163 VA, 125 W
115 Vac ± 10%, 47-63 Hz, 163 VA, 125 W
230 Vac ± 10%, 47-63 Hz, 163 VA, 125 W

DC OUTPUT

Voltage and current can be programmed via front panel control or
remote analog control over the following ranges;

E3614A:
E3615A:
E3616A:
E3617A:

0 - 8 V, 0 - 6 A
0 - 20 V, 0 - 3 A
0 - 35 V, 0 - 1.7 A
0 - 60 V, 0 - 1 A

*OUTPUT TERMINALS

The output terminals are provided on the front and rear panel.
They are isolated from the chassis and either the positive or neg­ative terminal may be connected to the ground terminal.

LOAD REGULATION

Constant Voltage - Less than 0.01% plus 2 mV for a full load to no
load change in output current.
Constant Current
maximum change in output voltage.

- Less than 0.01% plus 250 µA for a zero to

LINE REGULATION

Constant Voltage - Less than 0.01% plus 2 mV for any line volt­age change within the input rating.
Constant Current
age change within the input rating.

- Less than 0.01% plus 250 µA for any line volt-

PARD (Ripple and Noise)

Constant Voltage: Less than 200 µV rms and 1 mV p-p

Constant Current:

(20 Hz-20 MHz).
E3614A: Less than 5 mA rms
E3615A:
E3616A:
E3617A:

Less than 2 mA rms
Less than 500 µA rms
Less than 500 µA rms

OPERATING TEMPERATURE RANGE

0 to 40oC for full rated output. Maximum current is derated 1%
per degree C at 40

o

C-55oC.

*TEMPERATURE COEFFICIENT

Maximum change in output per oC after a 30-minute warm-up.
Constant Voltage:
Constant Current:

Less than 0.02% plus 500 µV.
E3614A: Less than 0.02% plus 3 mA
E3615A:
E3616A:
E3617A:

Less than 0.02% plus 1.5 mA
Less than 0.02% plus 1 mA
Less than 0.02% plus 0.5 mA

*STABILITY (OUTPUT DRIFT)

Maximum change in output for an 8 hours following a 30 minute
warm-up under constant line, load and ambient temperature.
Constant Voltage:
Constant Current:

Less than 0.1% plus 5 mV
Less than 0.1% plus 10 mA

LOAD TRANSIENT RESPONSE TIME

Less than 50 µsec for output recovery to within 15 mV following a
change in output current from full load to half load, or vice versa.

METER ACCURACY:

B±(0.5% of output + 2 counts)Bat

o

C

± 5

o

C

25

METER (PROGRAMMING) RESOLUTION

Voltage: E3614A 10 mV

Current:

E3615A
E3616A
E3617A
E3614A 10 mA
E3615A
E3616A
E3617A

10 mV (0 to 20 V), 100 mV (above 20 V)
10 mV (0 to 20 V), 100 mV (above 20 V)
10 mV (0 to 20 V), 100 mV (above 20 V)

10 mA
1 mA
1 mA

*OVERLOAD PROTECTION

A continuously acting constant current circuit protects the power
supply for all overloads including a direct short placed across the
terminals in constant voltage operation. The constant voltage cir­cuit limits the output voltage in the constant current mode of oper­ation.

*OVERVOLTAGE PROTECTION

Trip voltage adjustable via front panel control.

E3614A
Range: 2.5-10 V 2.5-23 V 2.5-39 V 5-65 V
Margin: Minimum setting above output voltage to avoid

false tripping: 4% of output + 2 V for all models

E3615A E3616A E3617A

*REMOTE ANALOG VOLTAGE PROGRAMMING (25 ± 5oC)

Remotely varied voltage from 0 to 10 V provides zero to maxi­mum rated output voltage or current.

Voltage:

The programming inputs are protected against input voltages up
to ±40 V.

Linearity 0.5% Current: Linearity 0.5%

REMOTE SENSING

Meets load-regulation specification when correcting for load-lead
drops of up to 0.5 V per lead with sense wire resistance of less
than 0.5 ohms per sense lead and lead lengths of less than 5
meters.

1-5

Table 1. Specifications and Operating Characteristics (Cont’d)

*REMOTE PROGRAMMING SPEED

Maximum time required for output voltage to change from initial
value to within a tolerance band (0.1%) of the newly programmed
value following the onset of a step change in the programming
input voltage.

Up: E3614A:

Down:

E3615A:
E3616A:
E3617A:
E3614A:
E3615A:
E3616A:
E3617A:

Full load No load

3 msec 2 msec
9 msec 6 msec
85 msec 85 msec

200 msec 200 msec

7 msec 1.6 sec
13 msec 2.2 sec
65 msec 1.8 sec

200 msec 3.2 sec

INSTALLATION

INITIAL INSPECTION

Before shipment, this instrument was inspected and found to be
free of mechanical and electrical defects. As soon as the instru­ment is unpacked, inspect for any damage that may have
occurred in transit. Save all packing materials until the inspection
is completed. If damage is found, a claim should be filed with the
carrier. The Agilent Technologies Sales and Service office should
be notified.

Mechanical Check

This check should confirm that there are no broken knobs or connec­tors, that the cabinet and panel surfaces are free of dents and
scratches, and that the meter is not scratched or cracked.

DC ISOLATION

± 240 Vdc maximum between either output terminal and earth
ground including the output voltage.

*COOLING:

*WEIGHT:

* Operating Characteristics

instructions.

Convection cooling is employed.

12.1 lbs/5.5 Kg net, 14.9 lbs/6.75 Kg shipping.

Electrical Check

The instrument should be checked against its electrical specifi­cations. Paragraph "TURN-ON CHECKOUT PROCEDURE" con­tains a brief checkout procedure and "PERFORMANCE TEST" in
section SERVICE INFORMATION includes an instrument perfor­mance check to verify proper instrument operation.

INSTALLATION DATA

The instrument is shipped ready for bench operation. It is neces­sary only to connect the instrument to a source of power and it is
ready for operation.

Location and Cooling

This instrument is air cooled. Sufficient space should be allowed so
that a free flow of cooling air can reach the sides and rear of the
instrument when it is in operation. It should be used in an area where
the ambient temperature does not exceed 40
derated 1% per

o

C at 40oC-55oC.

Outline Diagram

Figure 1 is a outline diagram showing the dimensions of the
instrument.

Rack Mounting

This instrument may be rack mounted in a standard 19-inch rack
panel either by itself or alongside a similar unit. Please see
ACCESSORY, page 1-4, for available rack mounting accesso­ries. Each rack-mounting kit includes complete installation

o

C. Maximum current is

Figure 1. Outline Diagram

INPUT POWER REQUIREMENTS

This power supply may be operated from nominal 100, 115, or
230 Vac 47-63 Hertz power source. A label on the rear panel
shows the nominal input voltage set for the unit at the factory. If
necessary, you can convert the supply to another nominal input
voltage by following the instructions below

Line Voltage Option Conversion

Line voltage conversion is accomplished by adjusting two compo­nents: the line select switch and the rear panel fuse F1. To con­vert the supply from one line voltage option to another, proceed
as follows:

a.Disconnect power cord.
b.Turn off the supply and remove the top cover by lifting the

cover upwards after taking it off from both sides of the chassis
by inserting a flat-blade screwdriver into the gap on the lower
rear portion of the cover.

c.Set two sections of the line voltage selector switch on the PC

board for the desired line voltage (see Figure 2).

d.Check the rating of the fuse F1 installed in the rear panel fuse

holder and replace with the correct fuse if necessary. For 100
and 115 V operation, use a normal blow 2 A fuse and for 230
V use a time delay 1 A fuse.

1-6

e. Replace the cover and mark the supply clearly with a tag or

label indicating the correct line voltage and fuse that is in
use.

Figure 2. Line Voltage Selector (set for 115 Vac)

Power Cord

To protect operating personnel, the instrument should be
grounded. This instrument is equipped with a three conductor
power cord. The third conductor is the ground conductor and
when the power cord is plugged into an appropriate receptacle,
the supply is grounded.

The power supply was shipped with a power cord for the type of
outlet used at your location. If the appropriate cord was not
included, contact your nearest Agilent Sales Office to obtain the
correct cord.

4. DISPLAY OVP/CC SET Switch: Pressing this switch causes
the VOLTS display to show voltage setting for overvoltage
shutdown (trip voltage) and the AMPS display to show the
current control set value. Setting values are either front panel
settings or remote voltage programmed settings.

5. OVP Adjust Screwdriver Control: While pressing the DIS­PLAY OVP/CC SET switch, rotating the control clock-wise
with a small, flat-blade screwdriver increases the setting for
overvoltage shutdown.

6. VOLTS Display: Digital display of actual output voltage, or
OVP shutdown setting.

7. AMPS Display: Digital display of actual output current, or
output-current setting.

8. CV LED Indicator: Output voltage is regulated when lighted.
This means the power supply is operating in the constant volt­age mode.

9. CC LED Indicator: Output current is regulated when lighted.
This means the power supply is operating in the constant cur­rent mode.

10. OVP LED Indicator: Output is shutdown by the occurrence
of an overvoltage when lighted. Removing the cause of over­voltage and turning the power off, then on, resets the power
supply.

TURN-ON CHECKOUT PROCEDURE

The following checkout procedure describes the use of the front
panel controls and indicators illustrated in Figure 3 and ensures
that the supply is operational:

OPERATING INSTRUCTIONS

INTRODUCTION

This section explains the operating controls and indicators and
provides information on many operating modes possible with your
instrument. The front panel controls and indicators are illustrated
in Figure 3.

Figure 3. Front-Panel Controls and Indicators

1. LINE Switch: Pressing this switch turns the supply on, or off.

2. VOLTAGE Control: Clockwise rotation increases output volt-
age.

3. CURRENT Control: Clockwise rotation increases output cur­rent.

MASTER

M/S 1 M/S 2

SLAVE

LOCAL

CV CC S ENSE

REMOTE

+

OUT+S-S

_

+

CV CC

+

__

VREF

A1 A2 A3 A4 A5

Figure 4. Switch Settings of Rear-Panel Control for Turn-

On Checkout

a. Disconnect power cord.
b. Check that the rear-panel switch settings are as shown in Fig-

ure 4.

c. Check that the rear panel label indicates that the supply is set

to match your input line voltage (If not, refer to "Line Voltage
Option Conversion".).

d. Check that the fuse on the rear panel is correct for your line

voltage.
e. Connect the power cord and push the LINE switch to ON.
f. While pressing OVP/CC SET switch, verify that the OVP

shutdown is set above 8.0, 20.0, 35.0, or 60.0 Vdc for

E3614A, E3615A, E3616A, or E3617A respectively. If not,

turn up OVP Adjust with a small flat-blade screwdriver.
g. Turn VOLTAGE control fully counter clockwise to ensure that

the output of VOLTS display decreases to 0 Vdc, then fully

clockwise to ensure that output voltage increases to the maxi-

mum output voltage.
h. While pressing OVP/CC SET switch, turn the CURRENT con-

trol fully counter clockwise and then fully clockwise to ensure

1-7

that the current limit value can be set from zero to maximum

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rated value.

OPERATING MODES

The setting of the rear panel switch determines the operatin
modes of the power supply. The local operating mode is set so
the power suppl
terminals (local sensin
trols (local pro

e sensing and remote programming of output voltage and

volta
current usin

LOCAL OPERA TING MODE

The power supply is shipped from the factory configured in the
local operatin
settin

s of the rear panel, as shown in Figure 4. The power sup-

provides constant voltage(CV) or constant current(CC) output.

pl

Constant Voltage Operaton

To set up a power supply for constant voltage operation, proceed
as follows:

senses the output voltage directly at the output

) for operation using the front panel con-

ramming). Other operating modes are: remote

external voltages.

mode. Local operating mode requires the switch

False OVP shutdowns ma
too close to the suppl
down volta
a

e to avoid false shutdowns from load-induced transients.

usting OVP.

Ad

down volta

a. With the VOLTAGE control full

b. While depressin

c. Follow the procedure for CC or CV operaton to set the out-

Resettin

turning power off. Wait one or more seconds, and turn power on
a

ain. If OVP shutdown continue to occur, check the connections

to the load and sense terminals, and check the OVP limit settin

e 4% of output +2.0 V or more above the output volt-

Follow this procedure to adjust the OVP shut-

e.

the power suppl

the OVP Adjust control to the desired OVP shutdown usin
a small, flat-blade screwdriver.

put volta

e and current

OVP. If OVP shutdown occurs, reset the suppl

occur if you set the OVP shutdown

's operating voltage. Set the OVP shut-

counter clockwise, turn on

.

DISPLAY OVP/CC SET switch, adjust

..

a. Turn on the power suppl

trol for desired output volta

b. While depressin

turn CURRENT control for the desired current limit.
c. With power off connect the load to the output terminals.
d. Turn on the power suppl

actual operation, if a load change causes the current

Durin

limit to be exceeded, the power suppl

cross over to constant current mode and the output voltage

will drop proportionatel

and adjust 10-turn VOLTAGE con-

e (output terminals open).

DISPLAY OVP/CC SET switch, adjust 10-

. Verify that CV LED is lighted.

will automaticall

.

Constant Current Operation

To set up a power supply for constant current operation, proceed
as follows:

a. Turn on power suppl
b. While depressin

CURRENT control for the desired output current.
c. Turn up the VOLTAGE control to the desired volta
d. With power off connect the load to the output terminal.
e. Turn on power suppl

(If CV LED is li

settin

that is greater than the current setting multiplied by the
load resistance in ohms is required for CC operation.) Durin
actual operation, if a load chan
be exceeded, the power suppl
to constant volta
output current will drop proportionatel

.

DISPLAY OVP/CC SET switch, adjust

e limit.

and then verify that CC LED is lighted.

hted, choose a higher voltage limit. A voltage

e causes the voltage limit to

will automatically cross over

e operation at the preset voltage limit and

.

Overvoltage Protection (OVP)

Adjustable overvoltage protection guards your load against over-

e. When the voltage at the output terminals increases (or is

volta
increased b
set b
ables the output causin
zero. Durin

an external source) to the OVP shutdown voltage as

the OVP ADJUST control, the supply's OVP circuit dis-

the output voltage and current to drop to

OVP shutdown the OVP LED lights.

Strong electrostatic discharge to power supply can make
OVP trip and eventuall
effectivel

protect output loads from the hazardous ESD

crowbar the output, which can

current.

CONNECTING LOADS

The output of the supply is isolated from earth ground. Either out­put terminal ma
240 volts off
exceed 240 Vdc.

Each load should be connected to the power suppl
usin

separate pairs of connecting wires. This will minimize mutual

effects between loads and will retain full advantage of the

couplin
low output impedance of the power suppl
wires should be as short as possible and twisted or shielded to
reduce noise pick-up. (If a shield is used, connect one end to the
power suppl
ted.)

If load considerations require that the output power distribution
terminals be remotel
power suppl
distribution terminals via a pair of twisted or shielded wires and
each load separatel
nals. For this case, remote sensin

raph "Remote Voltage Sensing").

be grounded or the output can be floated up to

round. Total output voltage to ground must not

output terminals

. Each pair of connectin

round terminal and leave the other end unconnec-

located from the power supply, then the

output terminals should be connected to the remote

connected to the remote distribution termi-

should be used (See para-

OPERA TION BEYOND RATED OUTPUT

The output controls can adjust the voltage or current to values up
to 5% over the rated output. Althou
in the 5% overran

uaranteed to meet all of its performance specifications in this

ion.

re

e region without being damaged, it can not be

h the supply can be operated

1-8

REMOTE OPERA TING MODES

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Remote operating modes discussed below are remote voltage
sensin

and remote voltage programming. Y ou can set up the unit
for remote operatin
panel switch and connectin
nals to the load or the external volta

2

to 1.5 mm
pl

can be connected to the rear panel terminals by sim-

push fitting. Thinner wires or conductors are inserted into the

connection space after depressin

Turn off the supply while making changes to rear panel
switch settin
of damage to the load and OVP shutdown from unin­tended output.

Remote Voltage Sensing

Remote voltage sensing is used to maintain good regulation at
the load and reduce the de
occur due to the volta

and the load. By connecting the supply for remote voltage

suppl

, voltage is sensed at the load rather than at the supply's

sensin
output terminals. This will allow the suppl
pensate for the volta
tion.

When the suppl
senses the volta
terminals.

modes by changing the settings of the rear

the leads from the rear panel termi-

e. Solid conductors of 0.75

the orange opening lever.

s or connections. This avoids the possibilit

radation of regulation that would

e drop in the leads between the power

to automatically com-

e drop in the load leads and improve regula-

is connected for remote sensing, the OVP circuit

e at the sense leads and not the main output

Output Noise.

appear at the suppl

ulation. Twist the sense leads to minimize the pickup of exter-

re

An

noise picked up on the sense leads will

's output voltage and may degrade CV load

nal noise and run them parallel and close to the load leads. In
nois

environments, it may be necessary to shield the sense
leads. Ground the shield at the power suppl
the shield as one of the sensin

Stability.

When the suppl

conductors.

is connected for remote sensing, it is

end only. Do not use

possible for the impedance of the load wires and the capacitance
of the load to form a filter, which will become part of the suppl
CV feedback loop. The extra phase shift created b

rade the supply's stability and can result in poor transient

de
response performance or loop stabilit

. In extreme cases, it can

this filter can

cause oscillations. Keep the leads as short as possible and twist
the leads of the load to eliminate the load lead inductance and
keep the load capacitance as small as possible.The load leads
should be of the lar
the volta

e drop in each lead to 0.5 volts.

The sense leads are part of the suppl

est diameter practical, heavy enough to limit

's programming feedback
control loop. Accidental open-connections of sense or load leads
durin

remote sensing operation have various unwanted effects.

Provide secure, permanent connections-especiall

for the sense

leads.

_

MASTER

LOCAL

_

+

_

+

+

's

Remote voltage sensing compensates for a voltage drop of
up to 0.5 V in each load, and there ma

be up to a 0.1 V
drop between the output terminal and the internal sensin
resistor, at which point the OVP circuit is connected. There­fore, the volta
much as 1.1 V more than the volta
load. It ma
when usin

CV Re

ulation.

adds directl

e sensed by the OVP circuit could be as

e being regulated at the

be necessary to re-adjust the OVP trip voltage

remote sensing.

Notice that an

voltage drop in the sense leads

to the CV load regulation. In order to maintain the
specified performance, keep the sense lead resistance to 0.5
ohms per lead or less.

Remote Sensin

chan

settings of the rear panel switch and connecting the

Connections.

Remote sensin

requires

load leads from + and - output terminals to the load and connect­in

the sense leads from the +S and -S terminals to the load as

shown in Fi

ure 5.

Observe polarity when connecting the sensing leads to
the load.

SLAVE

CV CC SENSE

REMOTE

+

nqcf

_

OUT

+S

-S

pqvg\BvB BB B B

CV CC

VREF

A1 A2 A3 A4 A5

M/S 1 M /S 2

Figure 5. Remote Voltage Sensin

Remote Analog Voltage Programming

Remote analog voltage programming permits control of the regu­lated output volta
a

e. The programming (external) voltage should not exceed 10
volts. The stabilit
the stabilit
disabled durin

The supply includes clamp circuits to prevent it from
suppl
or current when the remote pro

reater than 10 Vdc. Do not intentionally operate the sup-

e or current by means of a remotely varied volt-

of the programming voltages directly affects

of the output. The voltage control on the front panel is

remote analog programming.

more than about 120% of rated output voltage

ramming voltage is

1-9

ply above 100% rated output. Limit your programming

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volta

e to 10 Vdc.

Remote Programming Connections. Remote programmin
requires changing settings of the switch and connecting external
volta

es to + and - terminals of "CV" or "CC" on the rear panel.

noise picked up on the programming leads will appear on the

An

's output and may degrade regulation. To reduce noise

suppl
pick-up, use a twisted or shielded pair of wires for pro
with the shield

rounded at one end only. Do not use the shield as

ramming,

a conductor.
Notice that it is possible to operate a power suppl

neousl

in the remote sensing and the remote analog program-

modes.

min

Remote Pro

rear panel switch settin
volta

ramming voltage produces a change in output voltage (volt-

pro

ain) as follows: E3614A: 0.8 Vdc, E3615A: 2 Vdc, E3616A:

a

ramming, Constant Voltage. Figure 6 shows the

s and terminal connections for remote-

e control of output voltage. A 1 Vdc change in the remote

simulta-

3.5 Vdc, E3617A: 6 Vdc

_

MASTER

M/S 1 M/S 2

SLAVE

NOTE:
See the supplementar

ramming voltage source.

isolated pro

LOCAL

CV CC SENSE

REMOTE

Manual, if you are not using

_

+

OUT

+S

_

+

+

CV CC

VREF

A1 A2 A3 A4 A5

-S

MULTIPLE-SUPPLY OPERATION

Normal parallel and auto-parallel operation provides increased out­put current while normal series and auto-series provides increased
output volta

e of more than one supply. You can set up the unit for multiple-

a
suppl
and connectin

Solid conductors of 0.75 to 1.5 mm
panel terminals b
are inserted into the connection space after depressin
openin

NORMAL P ARALLEL OPERATION

Two or more power supplies being capable of CV/CC automatic
cross over operation can be connected in parallel to obtain a total
output current
The total output current is the sum of the output currents of the
individual power supplies. The output of each power suppl
be set separatel
pl

should be set to the desired output voltage; the other power

suppl

with the higher output voltage setting will deliver its constant

pl
current output, and drop its output volta
put of the other suppl
stant volta
output current which is necessar

ure 8 shows the rear panel switch settings and terminal con-

Fi
nections for normal parallel operation of two supplies.

POWER SUPPLY

e. Auto-tracking provides single control of output volt-

operation by changing the settings of the rear panel switch

the leads from the rear panel terminals to the load.

2

can be connected to the rear

simply push fitting. Thinner wires or conductors

the orange

lever.

reater than that available from one power supply.

. The output voltage controls of one power sup-

should be set for a slightly higher output voltage. The sup-

e until it equals the out-

, and the other supply will remain in con-

e operation and only deliver that fraction of its rated

to fulfill the total load demand.

MASTER

LOCAL

_

+

__

+

+

can

Figure 6. Remote Voltage Programming, Constant

Volta

e

Remote Programming, Constant Current. Figure 7 shows the

rear panel switch settin

e control of output current. A 1 Vdc change in the remote

volta

ramming voltage produces a change in output current (cur-

pro
rent

ain) as follows: E3614A: 0.6 Adc, E3615A: 0.3 Adc,

s and terminal connections for remote-

E3616A: 0.17 Adc, E3617A: 0.1 Adc

_

MASTER

M/S 1 M/S 2

SLAVE

NOTE:
See the supplementar

ramming voltage source.

isolated pro

LOCAL

CV CC SENSE

REMOTE

Manual, if you are not using

_

+

OUT

+S

_

+

+

CV CC

VREF

A1 A2 A3 A4 A5

-S

Figure 7. Remote Voltage Programming, Constant

Current

Remote Programming Speed. See the table of Specifications,

e 1-5.

pa

SLAVE

MASTER

SLAVE

CV CC SENSE

REMOTE

LOCAL

CV CC SENSE

REMOTE

OUT

+S -S

LOAD

_

+

OUT

+S

VREF

CV CC

+

-S

CV CC

A1 A2 A3 A4 A5

_

_

+

VREF

A1 A2 A3 A4 A5

M/S 1 M/S 2

POWER SUPPLY

M/S 1 M/S 2

Figure 8. Normal Parallel Operation of Two Supplies

AUTO-PARALLEL OPERATION

Auto-parallel operation permits equal current sharing under all load
conditions, and allows complete control of output current from one
master suppl
units are called slaves. Normall
model number should be connected for auto-parallel operation,
since the supplies must have the same volta
rent monitorin
each slave is approximatel
ure 10 show the rear panel switch settin
for auto-parallel operation of two supplies and three supplies.

. The control unit is called the master; the controlled

, only supplies having the same

e drop across the cur-

resistor at full current rating. The output current of

equal to the master's. Figure 9 and Fig-

s and terminal connections

1-10

Settin

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Voltage and Current. Turn the slave unit's CURRENT

control full
desired output volta
in a completel
stant volta

clockwise. Adjust the master unit's controls to set the

e and current. The master supply operates

normal fashion and may be set up for either con-

e or constant current operation as required. Verify that

the slave is in CV operation.

ramming according to the remote-programming instructions.

MASTER POWER SUPPLY

MASTER

LOCAL

_

+

__

+

+

For auto-parallel operation of two supplies, the combined output
volta

e is the same as the master unit's voltage setting, and the

combined output current is two times the master unit's current. In

eneral, for two supplies, the auto-parallel output current(Io) is

Io = Im + Is = 2Im

where Im = master unit's output current

Is = slave unit's output current

Proportional currents from auto-paralleled units require
equal load-lead volta
the load usin
to provide equal volta
not feasible, connect each suppl
terminals usin
connect the distribution terminals to the load with a sin

e drops. Connect each supply to

separate pairs of wire with length chosen

e drops from pair to pair. If this is

to a pair of distribution

equal- voltage-drop wire pairs, and then

le

pair of leads.

MASTER POWER SUPPLY

MASTER

SLAVE

MASTER

SLAVE

CV CC SENSE

CV CC SENSE

M/S 1 M/S 2

SLAVE POWER SUPPLY

M/S 1 M/S 2

LOCAL

REMOTE

LOCAL

REMOTE

_

+

OUT

+S

+S

-S

LOAD

_

+

OUT

-S

+

CV CC

_

+

CV CC

+

+

__

VREF

_

VREF

A1 A2 A3 A4 A5

A1 A2 A3 A4 A5

Figure 9. Auto-Parallel Operation of Two Supplies

M/S 1 M/S 2

CV CC SENSE

SLAVE

SLAVE POWER SUPPLY

MASTER

M/S 1 M/S 2

CV CC SENSE

SLAVE

SLAVE POWER SUPPLY

MASTER

M/S 1 M/S 2

CV CC SENSE

SLAVE

REMOTE

LOCAL

REMOTE

LOCAL

REMOTE

OUT

+S

_

+

OUT

+S -S

_

+

OUT

+S

-S

CV CC

LOAD

+

+

CV CC VREF A1 A2 A3 A4 A5

+

+

-S

CV CC

VREF

__

__

VREF

A1 A2 A3 A4 A5

A1 A2 A3 A4 A5

Figure 10. Auto-Parallel Operation of Three Supplies

NORMAL SERIES OPERA TION

Series operation of two or more power supplies can be accom­plished up to the output isolation ratin
obtain a hi

her voltage than that available from a single supply.
Series connected supplies can be operated with one load across
both supplies or with a separate load for each suppl
power supplies have a reverse polarit
the output terminals so that if operated in series with other sup­plies, dama
suppl

e will not occur if the load is short-circuited or if one

is turned on separately from its series partners. When this
connection is used, the output volta
of the individual supplies. Each of the individual supplies must be
adjusted in order to obtain the total output volta
shows the rear panel switch settin
normal series operation of two supplies.

POWER SUPPLY

MASTER

LOCAL

+

of any one supply to

. These

diode connected across

e is the sum of the voltages

e. Figure 11

s and terminal connections for

_

__

+

+

Overvoltage Protection. Adjust the desired OVP shutdown limit

the master unit's OVP Adjust control. Set the slave units'

usin
OVP limits above the master's. When a master-unit shuts down,
the master pro
slave unit shuts down, it shuts onl
rent is

rams the slave units to zero voltage output. If a

itself down. If the required cur-

reat enough, the master will switch from CV to CC opera-

tion.

Remote Sensin

connect remote-sense leads onl
the remote-sensin

Remote Analo

auto-parallel operation, set up onl

. To remote sense with auto-parallel operation,

to the master unit according to

instructions.

Voltage Programming. To remote program with

the master unit for remote pro-

M/S 1 M/S 2

POWER SUPPLY

M/S 1 M/S 2

SLAVE

MASTER

SLAVE

CV CC SENSE

REMOTE

LOCAL

CV CC SENSE

REMOTE

OUT

+S -S

LOAD

_

+

OUT

+S

VREF

CV CC

+

-S

CV CC

A1 A2 A3 A4 A5

_

_

+

VREF

A1 A2 A3 A4 A5

Figure 11. Normal Series Operation of Two Supplies

1-11

AUTO-SERIES OPERATION

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(S2)

Auto-series operation permits equal or proportional voltage
sharin

, and allows control of output voltage from one master
unit. The volta
the front panel VOLTAGE control on the master and volta
divider resistor. The master unit must be the most positive sup­pl

of the series. The output CURRENT controls of all series
units are operative and the current limit is equal to the lowest
settin

. If any output CURRENT controls are set too low, auto­matic cross over to constant current operation will occur and the
output volta
panel switch settin
operation of two supplies and three supplies. This mode can

ive ±voltage tracking operation of two supplies with two

also
separate loads.

e of the slaves is determined by the setting of

e will drop. Figure 12 and Figure 13 show the rear

s and terminal connections for Auto-series

above the master unit's current settin

to avoid having the slave

switch to CC operation.
When in CC operation the combined output current is the same

e

as the master unit's current settin
combined output volta
slave unit's output volta

Overvolta

e Protection.

e is the sum of the master unit's and the

es.

Set the OVP shutdown volta
unit so that it shuts down at a volta
durin

auto-series operation. When a master unit shuts down, it pro-

, and when in CV operation the

e in each

e higher than its output voltage

rams any slave units to zero output. When a slave unit shuts down,

it shuts down onl

itself (and any slaves below it in the stack). The
master (and all slaves above the shut-down slave) continues to sup­pl

output voltage.

Mixed model numbers ma

be employed in auto-series combi-

nation without restriction, provided that each slave is specified as

capable of auto-series operation. If the master supply is set

bein
up for constant current operation, then the master-slave combina­tion will act as a composite constant current source.

T otal output voltage to ground must not exceed 240 Vdc.

Determining Resistors.

multiple) of the master unit's volta
the slave unit. Notice that the percenta

e contributed by each supply is independent of the magnitude

a
of the total volta

External resistors control the fraction (or

e setting that is supplied from

e of the total output volt-

e. For two units in auto-series the ratio of R1 to

R2 is

(R1+R2)/R1 = (Vo/Vm)
R2/R1 = (Vs/Vm)

Where Vo = auto-series volta

Vm = master unit's output volta
Vs = slave unit's output volta

For example, usin

the E3617A as a slave unit and putting R2=50

e = Vs + Vm

e

e

kΩ (1/4 watt), then from the above equations,

R1 = R2(Vm/Vs) = 50(Vm/Vs) kΩ

In order to maintain the temperature coefficient and stabilit
mance of the suppl

, choose stable, low noise resistors.

perfor-

MASTER POWER SUPPLY

MASTER

SLAVE

MASTER

SLAVE

CV CC SENSE

CV CC SENSE

M/S 1 M/S 2

SLAVE POWER SUPPLY

M/S 1 M/S 2

LOCAL

REMOTE

LOCAL

REMOTE

_

+

OUT

+S -S

LOAD

_

+

OUT

+S

-S

+

CV CC

_

+

CV CC

+

+

__

VREF

_

VREF

A1 A2 A3 A4 A5

R1 R2

A1 A2 A3 A4 A5

Figure 12. Auto-Series Operation of Two Supplies

MASTER POWER SUPPLY

MASTER

M/S 1 M/S 2

SLAVE

SLAVE POWER SUPPLY(S1)

MASTER

LOCAL

CV CC SENSE

REMOTE

LOCAL

LOAD

_

+

OUT

+S

-S

_

+

+

CV CC

+

+

+

__

VREF

R1 R2

__

A1 A2 A3 A4 A5

M/S 1 M/S 2

It is recommended to connect a 0.1 µF capacitor in paral­lel with R2 in two supplies operation or R2 and R4 in

CV CC SENSE

SLAVE

SLAVE POWER SUPPLY(S2)

MASTER

REMOTE

LOCAL

OUT

+S

-S

_

+

CV CC

+

+

VREF

R3 R4

__

A1 A2 A3 A4 A5

three supplies operation to ensure the stable operation.

Setting Voltage and Current.

set the desired output volta
of the slave unit is disabled. Turnin
master unit will result in a continuous variation of the output of the
series combination, with the contribution of the master's output

e to that of the slave's voltage always remaining in the ratio

volta
of the external resistors. Set the CURRENT control of slave unit

Use the master unit's controls to

e and current. The VOLTAGE control

the voltage control of the

M/S 1 M/S 2

CV CC SENSE

SLAVE

Vo=Vm(1+

ure 13. Auto-Series Operation of Three Supplies

Fi

REMOTE

R2

R4

R2

)

+

R1

R1

R3

OUT

+S

Where Vo = Auto-Series volta

-S

CV CC

Vm = master unit's output volta
Vs1 = slave(S1) unit's output volta
Vs2 = slave

unit's output voltage

VREF

A1 A2 A3 A4 A5

e = Vm + Vs1 + Vs2

e

e

1-12

Remote Sensin

g

g

g

g

y

g

g

g

g

y

y

y

g

y

y

y

g

g

g

g

g

g

g

g

g

g

g

g

y

g

g

g

g

g

g

g

g

y

y

g

g

g

g

g

g

g

. To remote sense with auto-series operation,
set SENSE switch of the master unit and set SENSE switch of the
slave unit to remote.

Remote Analo

Voltage Programming. To remote analog pro-

ram with auto-series operation, connect program (external) volt-

es to the "CV" or "CC"" terminal of the master unit and set "CV"

a
or "CC" switch of the master unit to remote.

AUTO-TRACKING OPERATON

Auto-tracking operation of power supplies is similar to auto-series
operation except that the master and slave supplies have the
same output polarit
This operation is useful where simultaneous turn-up, turn-down or
proportional control of all power supplies is required.

Fi

ure 14 and Figure 15 show two and three supplies connected
in auto-trackin
to

ether as a common or ground point. For two units in auto-

a fraction R2/(R1+R2) of the output of the master suppl

trackin
is provided as one of the inputs to the comparison amplifier of the
slave suppl

in an auto-tracking operation must be the positive supply hav-

pl
in

the largest output voltage. Turn-up and turn-down of the

, thus controlling the slave's output. The master sup-

power supplies are controlled b
maintain the temperature coefficient and stabilit
the power suppl
noise, low temperature.

with respect to a common bus or ground.

with their negative output terminals connected

the master supply. In order to

specifications of

, the external resistor should be stable, low

Remote Analo

Programming. To simultaneously remote pro-

ram both units' output voltages, set up only the master unit for

remote volta

instructions. To vary the fraction of the output voltage contri-

min
bution b
in two units operation. To independentl
unit's output current settin
output current accordin

e programming according to the remote program-

the slave unit, connect a variable resistor in place of R2

remote program each

, set up each unit for remote control of

to the instructions under "Remote Pro-

ramming, Constant Current" paragraph.

MASTER POWER SUPPLY

MASTER

CV CC SENSE

M/S 1 M/S 2

SLAVE

SLAVE POWER SUPPLY

MASTER

CV CC SENSE

M/S 1 M/S 2

SLAVE

LOCAL

REMOTE

LOCAL

REMOTE

_

+

OUT

+S -S

LOAD

LOAD

_

+

OUT

+S

-S

+

CV CC

_

+

CV CC

+

+

__

VREF

_

VREF

A1 A2 A3 A4 A5

R1 R2

A1 A2 A3 A4 A5

Figure 14. Auto-Tracking Operation of Two Supplies

Determinin

the master unit's volta
two units in auto-trackin

Resistors. External resistors control the fraction of

e that is supplied from the slave unit. For

the ratio R1 and R2 is

R2/(R1+R2 = (Vs/Vm)
Where Vm = master output volta

Vs = slave output volta

e

e

It is recommended to connect a 0.1 µF capacitor in paral­lel with R2 in two supplies operation or R2 and R4 in
three supplies operation to ensure the stable operation.

Setting Voltage and Current. Use the master unit's VOLTAGE con­trol to set the output volta
CV operation, the master's output volta
volta

e setting, and the slave's output voltage for two units operation

e from both units. When the master is in

e(Vm) is the same as its

is Vm(R2/(R1+R2)). The VOLTAGE control of the slave unit is dis­abled. Set the CURRENT controls of master and slave units above
the required currents to assure CV operation of master and slave
units.

Overvolta

unit so that it shuts down at a volta
a

e during auto-tracking operation. When a master unit shuts
down, it pro
unit shuts down, it shuts down onl

Remote Sensin

e Protection. Set the OVP shutdown voltage in each

e higher than its output volt-

rams any slave units to zero output. When a slave

itself.

. To include remote sensing with auto-trackin
operation independently, set up each unit for remote sensin
according to the remote-sensing instructions under previous

raph.

para

MASTER POWER SUPPLY

MASTER

M/S 1 M/S 2

SLAVE

SLAVE POWER SUPPLY(S1)

MASTER

M/S 1 M/S 2

SLAVE

SLAVE POWER SUPPLY(S2)

MASTER

M/S 1 M/S 2

SLAVE

R2

Vs1 =

R1+

R4

Vs2 =

R3+

Fi

ure 15. Auto-Tracking Operation of Three Supplies

CV CC SENSE

REMOTE

LOCAL

CV CC SENSE

REMOTE

LOCAL

CV CC SENSE

REMOTE

Vm

R2

Vs1

R4

LOCAL

Where

_

+

OUT

+S

+S

+S

-S

LOAD

LOAD

_

+

OUT

-S

LOAD

_

+

OUT

-S

Vm = masters unit's output volta
Vs1 = slave(S1) unit's output volta
Vs2 = slave(S2) unit's output volta

+

CV CC

+

CV CC

+

CV CC

+

+

+

__

VREF

A1 A2 A3 A4 A5

R1 R2

__

VREF

A1 A2 A3 A4 A5

R3 R4

__

VREF

A1 A2 A3 A4 A5

e

e
e

1-13

LOAD CONSIDERATIONS

y

g

g

y

g

g

g

y

g cy

y

g

y

y

g cy

y

g

y

y

g

g

g

g

y

g

y

g

g

y

y

g

g

y

g

y

g

g

g

y

y

g

y

y

g

y

g

This section provides information on operating your supply with
various t

PULSE LOADING

The power supply will automatically cross over from constant­volta
(over the preset limit) in the output current. Althou
limit ma
currents (as occur in pulse loadin
rent limit and cause cross over to occur. If this cross over limitin
is not desired, set the preset limit for the peak requirement and
not the avera

REVERSE CURRENT LOADING

An active load connected to the power supply may actuall
deliver a reverse current to the power supply during a portion of
its operatin
pump current into the suppl
ble dama
these effects, it is necessar
load resistor so that the power supply delivers current through the
entire operatin

pes of loads connected to its output.

e to constant current operation in response to an increase

h the preset

be set higher than the average output current, high peak

) may exceed the preset cur-

e.

cle. An external source can not be allowed to

without loss of regulation and possi-

e to the output capacitor of the power supply. To avoid

to preload the supply with a dumm

cle of the load devices.

a. The output impedance of the power suppl

increasin

b. The recover

resistance chan

c. A lar

load occurs when the load resistance is reduced rapidl

frequency.

time of the output voltage is longer for load

es.

e surge current causing a high power dissipation in the

decreases with

.

REVERSE VOL TAGE LOADING

A diode is connected across the output terminals with reverse

. This diode protects the output electrolytic capacitors and

polarit
the series re
a

e applied across the output terminals. For example, in series
operation of two supplies, if the AC is removed from one suppl
the diode prevents dama
would otherwise result from a reverse polarit

Since series re
a

e, another diode is connected across the series transistor. This
diode protects the series re
operation if one suppl
before the other.

ulator transistors from the effects of a reverse volt-

e to the unenergized supply which

voltage.

ulator transistors cannot withstand reverse volt-

ulators in parallel or auto-parallel

of the parallel combination is turned on

BA TTER Y CHARGING

The power supply's OVP circuit contains a crowbar SCR, which
effectivel
an external volta
output, and OVP inadvertentl
sink a large current from the source; possibly damaging the supply.
To avoid this a diode must be connected in series with the output as
shown in Fi

shorts the output of the supply whenever the OVP trips. If

e source such as a battery is connected across the

triggered, the SCR will continuousl

ure 17.

,

Figure 16. Reverse Current Loading Solution

Figure 17. Recommended Protection Circuit for

Batter

OUTPUT CAP ACITANCE

An internal capacitor, connected across the output terminals of
the power suppl
duration durin
added externall
decrease the safet
hi

h-current pulse may damage load components before the

e output current is large enough to cause the current limit-

avera

circuit to operate.

in

The effect of the output capacitor durin
tion are as follows:

, helps to supply high-current pulses of short

constant voltage operation. Any capacitance

will improve the pulse current capability, but will

provided by the current limiting circuit. A

constant current opera-

1-14

Chargin

SERVICE INFORMATION

Figure A-1. Block Diagram

PRINCIPLES OF OPERATION

(Block Diagram Overview)

Throughout this discussion, refer to both the block diagram of
Figure A-1 and the schematic diagrams at the rear of the
manual. The input ac line voltage is first applied to the prereg­ulator which operates in conjunction with the SCR control cir­cuit (preregulator control circuit) to rectify the tap switched AC
voltage. This preregulator minimizes the power dissipated in
the series regulating elements by controlling the dc level
across the input filter capacitor, depending on the output volt­age.

To achieve this, tap switching is accomplished by four SCRs
and one bridge diode (CR10, CR12, CR15, CR18 and CR13)
and the SCR control circuit. By selecting different SCR firing
combinations from SCR control circuit, these circuits allow the
input capacitors (C7 and C8) to charge to one of four discrete
voltage levels, depending on the output voltage required.

The main secondary winding of the power transformer has
three sections (N1, N2, and N3), each of which has a different
turns ratio with respect to the primary winding. At the begin­ning of each half-cycle of the input ac, the control circuit
determines whether one pair, both or none of the SCR will be
fired. If neither SCR is fired, the bridge diode (CR13) receives
an ac input voltage that is determined by N1 turns and the
input capacitors charge to a corresponding level. If SCR
CR15 and CR18 are fired, input capacitors charge to the volt­age determined by N1+N2 turns. Similarly, if CR10 and CR12
are fired the capacitors are charged by N1 + N3. Finally, if all
SCRs are fired simultaneously, input capacitors charge to its
highest voltage level determined by N1 + N2 + N3 turns.

The SCR control circuit determines which SCRs are to be
fired by monitoring the output voltage and comparing these
values against a set of three internally derived reference lev­els. These three reference levels are translated into boundary
lines to allow the output characteristic to be mapped into four
operating regions (Figure A-2). The boundary lines, which are
invisible to the user, are divided into four operating regions
(V1, V2, V3, and V4) to minimize the power dissipation in the

A-1