KEPCO JQE 25-20MVPY-27274 Instruction Manual

INSTRUCTION MANUAL

JQE 25-20MVPY-27274

POWER SUPPLY

MODEL

KEPCO INC.

An ISO 9001 Company.

IMPORTANT NOTES:

1) This manual is valid for the following Model and associated serial numbers:

MODEL SERIAL NO. REV. NO.

2) A Change Page may be included at the end of the manual. All applicable changes and
revision number changes are documented with reference to the equipment serial num­bers. Before using this Instruction Manual, check your equipment serial number to identify
your model. If in doubt, contact your nearest Kepco Representative, or the Kepco Docu­mentation Office in New York, [phone], requesting the correct revision for your
particular model and serial number.

3) The contents of this manual are protected by copyright. Reproduction of any part can be
made only with the specific written permission of Kepco, Inc.

Data subject to change without notice.

JQE 25-20MVPY-27274

POWER SUPPLY

INSTRUCTION MANUAL

ORDER NO. REV. NO.

©2011, KEPCO, INC.
P/N 243-1333-b

KEPCO, INC. z 131-38 SANFORD AVENUE z FLUSHING, NY. 11355 U.S.A. z TEL [phone] z FAX [phone]

KEPCO®

THE POWER SUPPLIER™

email: [e-mail] z World Wide Web: http://www.kepcopower.com

Declaration of Conformity

Application of Council directives:

Standard to which Conformity is declared:

EN61010-1:2001 (Safety requirements for electrical equipment for measurement,

control and laboratory use - Part 1)

Manufacturer's Name and Address:

Importer's Name and Address:

Type of Equipment:

Model No.:

73/23/EEC (LVD)
93/68/EEC (CE mark)

KEPCO INC.
131-38 SANFORD AVENUE
FLUSHING, N.Y. 11352 USA

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T

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Component Power Supply

[PRODUCT MODEL NUMBER]

Y

Year of Manufacture:

I, the undersigned, declare that the product specified above, when used in conjunction with the condi­tions of conformance set forth in the product instruction manual, complies with the requirements of the
Low Voltage Directive 73/23/EEC, which forms the basis for application of the CE Mark to this product.

Place: KEPCO Inc.

131-38 Sanford Ave.
Flushing, N.Y.11352 USA

Saul Kupferberg

(Full Name)

Date:

228-1348 DC-COMP/INST 092611 A

VP OF SALES

(position)

Conditions of Conformance

When this product is used in applications governed by the requirements of the EEC, the following restric­tions and conditions apply:

1. For European applications, requiring compliance to the Low Voltage Directive, 73/23/EEC, this power
supply is considered a component product, designed for “built in“ applications. Because it is incom­plete in construction, the end product enclosure must provide for compliance to any remaining electri­cal safety requirements and act as a fire enclosure. (EN61010-1:2001, Cl. 6, Cl. 7, Cl.8, and Cl. 9)

2. This power supply is designed for stationary installation, with mains power applied via a detachable
power supply cord or via direct wiring to the source power terminal block.

3. This power supply is considered a Class 1 (earthed) product. It is intended for use as part of equip­ment meant for test, measurement and laboratory use, and is designed to operate from single phase,
three wire power systems. This equipment must be installed within a suitably wired equipment rack,
utilizing a three wire (grounded) mains connection. See wiring section of this manual for complete
electrical wiring instructions. (EN61010-1:2001, Cl.6.10.1)

4. This power supply has secondary output circuits that are considered hazardous, and which exceed
180W output power at a potential of 2V or more.

5. The output wiring terminals of this power supply has not been evaluated for field wiring and, therefore,
must be properly configured by the end product manufacturer prior to use.

6. This power supply employs a supplementary circuit protector in the form of a circuit breaker mounted
on the front panel. This circuit breaker protects the power supply itself from damage in the event of a
fault condition. For complete circuit protection of the end product, as well as the building wiring, it is
required that a primary circuit protection device be fitted to the branch circuit wiring. (EN61010-1:2001,
Cl. 9.5)

7. Hazardous voltages are present within this power supply during normal operation. All operator adjust­ments to the product are made via externally accessible switches, controls and signal lines as speci­fied within the product operating instructions. There are no user or operator serviceable parts within
the product enclosure. Refer all servicing to qualified and trained Kepco service technicians.

B 228-1351 COND/CONFORM 092611

SAFETY INSTRUCTIONS

1. Installation, Operation and Service Precautions

This product is designed for use in accordance with EN 61010-1 and UL 3101 for Installation Category 2,
Pollution Degree 2. Hazardous voltages are present within this product during normal operation. The prod­uct should never be operated with the cover removed unless equivalent protection of the operator from
accidental contact with hazardous internal voltages is provided:

!

!

!

There are no operator serviceable parts or adjustments within the product enclosure.
Refer all servicing to trained service technician.

Source power must be removed from the product prior to performing any servicing.

This product is factory-wired for the nominal a-c mains voltage indicated on the rat­ing nameplate located adjacent to the source power connection on the product's rear
panel. To reconfigure the product input for other nominal mains voltages as listed
herein, the product must be modified by a trained service technician.

2. Grounding

This product is a Class 1 device which utilizes protective earthing to ensure operator safety.

The PROTECTIVE EARTHING CONDUCTOR TERMINAL must be properly con-

!

nected prior to application of source power to the product (see instructions on instal­lation herein) in order to ensure safety from electric shock.

PROTECTIVE EARTHING CONDUCTOR TERMINAL - This symbol indicates the
point on the product to which the protective earthing conductor must be attached.

EARTH (GROUND) TERMINAL - This symbol is used to indicate a point which is
connected to the PROTECTIVE EARTHING TERMINAL. The component installer/
assembler must ensure that this point is connected to the PROTECTIVE EARTH­ING TERMINAL.

CHASSIS TERMINAL -This symbol indicates frame (chassis) connection, which is
supplied as a point of convenience for performance purposes (see instructions on
grounding herein). This is not to be confused with the protective earthing point, and
may not be used in place of it.

3. Electric Shock Hazards

This product outputs hazardous voltage and energy levels as a function of normal operation. Operators
must be trained in its use and exercise caution as well as common sense during use to prevent accidental
shock.

This symbol appears adjacent to any external terminals at which hazardous voltage

!

228-1352 SAFETY - (COVER REMOVAL) 092611 C/(D BLANK)

levels as high as 500V d-c may exist in the course of normal or single fault condi­tions.

This symbol appears adjacent to any external terminals at which hazardous voltage
levels in excess of 500V d-c may exist in the course of normal or single fault condi­tions.

TABLE OF CONTENTS

SECTION PAGE

SECTION 1 - INTRODUCTION

1.1 Scope of Manual ..................................................................................................................................... 1-1

1.2 General Description................................................................................................................................. 1-1

1.3 Features. ................................................................................................................................................. 1-1

1.4 Accessories ............................................................................................................................................. 1-2

1.5 Specifications .......................................................................................................................................... 1-2

1.6 Specifications, Mechanical ...................................................................................................................... 1-4

SECTION 2 - INSTALLATION

2.1 Unpacking and Inspection ....................................................................................................................... 2-1

2.2 Terminations............................................................................................................................................ 2-1

2.3 AC Input Requirements ........................................................................................................................... 2-3

2.4 Cooling .................................................................................................................................................... 2-4

2.5 Preliminary Operational Check................................................................................................................ 2-4

2.6 Installation ............................................................................................................................................... 2-5

2.7 Grounding................................................................................................................................................ 2-5

SECTION 3 - OPERATION

3.1 Standard Power Supply Operation, Local Control................................................................................... 3-1

3.1.1 General.............................................................................................................................................. 3-1

3.2 Load Connection ..................................................................................................................................... 3-1

3.2.1 Local Error Sensing ........................................................................................................................... 3-1

3.2.2 Remote Error Sensing ....................................................................................................................... 3-2

3.2.3 Grounded Load Connection............................................................................................................... 3-2

3.3 Output Adjustment................................................................................................................................... 3-3

3.4 Introduction to Remote Programming ..................................................................................................... 3-3

3.4.1 General.............................................................................................................................................. 3-3

3.4.2 Equations Showing the Operation of the Kepco Bridge..................................................................... 3-5

3.5 General Rules for Remote Programming ................................................................................................ 3-6

3.5.1 Grounding.......................................................................................................................................... 3-6

3.5.2 Connections....................................................................................................................................... 3-6

3.5.3 Programming Resistors ..................................................................................................................... 3-6

3.5.4 External Switching ............................................................................................................................. 3-6

3.6 Output Voltage Programming With External Resistance......................................................................... 3-6

3.7 Constant Current Operation .................................................................................................................... 3-7

SECTION 4 - CALIBRATION

4.1 General.................................................................................................................................................... 4-1

4.2 Test Equipment Required........................................................................................................................ 4-1

4.3 Output Voltage Calibration ...................................................................................................................... 4-1

4.3.1 Voltage Pre-calibration Setup ............................................................................................................ 4-1

4.3.2 Zero Output Voltage Calibration ........................................................................................................ 4-2

4.3.2.1 Zero Output Voltage (Local Programming) Calibration................................................................ 4-2

4.3.2.2 Zero Output Voltage (Remote Programming) Calibration............................................................ 4-2

4.3.3 Zero VOLTAGE Monitor Calibration .................................................................................................. 4-2

4.3.4 Zero CURRENT Monitor Calibration.................................................................................................. 4-3

4.3.5 Local Full Scale (FS) Output Voltage Calibration .............................................................................. 4-3

4.3.6 Remote Full Scale (FS) Output Voltage Calibration .......................................................................... 4-3

4.3.7 Full Scale (FS) VOLTAGE Monitor Calibration.................................................................................. 4-3

4.4 Output Current Limit calibration............................................................................................................... 4-4

4.4.1 Current Limit Pre-calibration Setup.................................................................................................... 4-4

4.4.2 Full Scale (maximum) Output Current Limit Calibration .................................................................... 4-4

4.4.3 FS Current Monitor Calibration .......................................................................................................... 4-4

4.4.4 Minimum Output Current Check ........................................................................................................ 4-5

4.5 Overvoltage Protection (OVP) Test and Adjustment ............................................................................... 4-5

27274092611 i

TABLE OF CONTENTS

SECTION PAGE

SECTION 5 - THEORY OF OPERATION

5.1 Simplified Diagram Discussion ............................................................................................................... 5-1

5.2 Circuit Description................................................................................................................................... 5-1

5.2.1 A-C Input Circuit................................................................................................................................ 5-1

5.2.2 Main d-c Supply ................................................................................................................................ 5-3

5.2.3 Pass-Element Section....................................................................................................................... 5-3

5.2.4 Voltage Error Amplifier (VEA) ........................................................................................................... 5-3

5.2.5 Current Limit Circuit (CEA) ............................................................................................................... 5-4

5.2.6 Overvoltage Protection Circuit and Current Monitor ......................................................................... 5-4

5.2.7 Auxiliary Supplies.............................................................................................................................. 5-4

5.2.8 Metering Circuit................................................................................................................................. 5-5

5.2.9 Monitoring Circuit .............................................................................................................................. 5-5

SECTION 6 - MAINTENANCE

6.1 General ................................................................................................................................................... 6-1

6.2 Disassembly/Reassembly....................................................................................................................... 6-1

6.2.1 Cover Removal ................................................................................................................................. 6-1

6.2.2 A1 Circuit Board Removal................................................................................................................. 6-1

6.2.3 A5 Terminal Block Board and CR203 and CR204 Access ............................................................... 6-2

6.2.4 A3 Heat Sink Removal...................................................................................................................... 6-2

6.2.5 A4 Overvoltage Protection Circuit Board Removal ........................................................................... 6-2

6.2.6 Reassembly. ..................................................................................................................................... 6-2

6.3 Troubleshooting ...................................................................................................................................... 6-2

6.4 Power Supply Measurements................................................................................................................. 6-4

6.4.1 Required Test Equipment. ................................................................................................................ 6-4

6.4.2 Measurement Instructions................................................................................................................. 6-5

SECTION 7 - ELECTRICAL PARTS LIST AND DIAGRAMS

7.1 General ................................................................................................................................................... 7-1

7.2 Ordering Information............................................................................................................................... 7-1

7.3 Abbreviations Used in Kepco Parts Lists................................................................................................ 7-2

7.3.1 Reference Designators ..................................................................................................................... 7-2

7.3.2 Descriptive Abbreviations ................................................................................................................. 7-2

ii 27274092611

LIST OF FIGURES

FIGURE TITLE PAGE

1-1 Mechanical Outline Drawing ....................................................................................................................... 1-5

2-1 Front Panel Controls and Indicators, JQE Special Models ......................................................................... 2-1

2-2 Rear Panel Terminations, JQE Special Models .......................................................................................... 2-2

2-3 Location of Internal Adjustments ................................................................................................................ 2-3

2-4 Conversion to 230V AC Line Operation ...................................................................................................... 2-4

3-1 Load Connection Showing a Floating Load ................................................................................................ 3-1

3-2 Grounded Load Connections ...................................................................................................................... 3-2

3-3 Comparison Bridge (Simplified) for Voltage Mode ...................................................................................... 3-4

3-4 Comparison Bridge (Simplified) for Current Mode ...................................................................................... 3-4

3-5 Remote Resistance Programming (Voltage Mode)..................................................................................... 3-7

5-1 JQE Special Power Supply, Simplified Schematic Diagram ....................................................................... 5-2

6-1 A1 PC Board, Reassembly ......................................................................................................................... 6-1

7-1 JQE 25-20MVPY-27274 Power Supply, Component Locations ................................................................. 7-3

7-2 JQE 25-20MVPY-27274 A1 Assembly, Component Locations................................................................... 7-6

7-3 JQE 25-20MVPY-27274 A3 Assembly, Component Locations................................................................... 7-11

7-4 JQE 25-20MVPY-27274 A3A1 Assembly, Component Locations .............................................................. 7-12

7-5 JQE 25-20MVPY-27274 A3A2 Assembly, Component Locations .............................................................. 7-13

7-6 JQE 25-20MVPY-27274 A4 Assembly, Component Locations................................................................... 7-14

7-7 JQE 25-20MVPY-27274, Overall Schematic Diagram................................................................................ 7-17

7-8 Amplifier and Reference Board A1, Schematic Diagram ............................................................................ 7-19

7-9 Overvoltage Protection Board A4, Schematic Diagram .............................................................................. 7-21

27274092611

iii

LIST OF TABLES

TABLE TITLE PAGE

1-1 JQE 25-20MVPY-27274 Specifications ...................................................................................................... 1-2

2-1 Front Panel Controls and Indicator Functions ............................................................................................ 2-1

2-2 Rear Panel Termination Functions ............................................................................................................. 2-2

2-3 Internal Adjustments ................................................................................................................................... 2-3

6-1 Auxiliary Supply Voltages ........................................................................................................................... 6-3

iv 27274092611

SECTION 1 - INTRODUCTION

1.1 SCOPE OF MANUAL

This manual contains instructions for the installation, operation and maintenance of the specially
modified Kepco JQE 25-20MVPY-27274, “HALF-RACK” Power Supply, manufactured by Kepco,
Inc., Flushing, New York, U.S.A. This model is hereafter referred to as JQE Special Power Supply
or JQE Special. Additional copies of this manual can be downloaded from the Kepco web site at
http://www.kepcopower.com/support/opmanls.htm#jqe.

1.2 GENERAL DESCRIPTION

The Kepco JQE Special Power Supply is a unipolar, linear, precision regulated voltage source in
a half-rack configuration. The power supply has a rectangular voltage-current limit output char­acteristic. It features full range voltage control, from zero to the nominal output voltage value,
and current limit control, from a small offset of 0.5% of nominal output current to the nominal
output current value. The JQE can be operated as either a voltage source or a current source.

The input source power is an a-c line, single phase, either 115V or 230V a-c (nominal) value.
The nominal a-c input value is established by changing some jumpers on the power trans­former's terminal block.

The JQE Special power supply has linear, full-dissipation series-regulators (NPN) driven by an
integrated circuit operational amplifier. A sharp current-limit circuit enables current control oper­ation of the power supply. The output voltage of the JQE power supply can be programmed
remotely. All necessary connections are available on terminals at the rear barrier-strip.

The compact design of the JQE Specials was made possible by a unique heatsink design of
exceptional efficiency in combination with highly reliable low-noise fans. All JQE power supplies
feature all-silicon design with conservatively rated components for added reliability.

1.3 FEATURES.

The JQE Special includes the following features:

a) Two panel meters which permit simultaneous monitoring of the output voltage and out-

put current.

b) Overvoltage Protection. This protection acts simultaneously on the circuit breaker’s volt-

age coil and the electrical “crowbar” that shorts the output through a silicon-controlled
rectifier (SCR) if the output voltage exceeds a preadjustable limit on the sensing lines
(see Table 1-1 for specifications).

c) Zero and full scale voltage calibration for local front panel voltage control.

d) Full scale current calibration for CURRENT LIMIT.

e) Zero and full scale current calibration for VOLTAGE MONITOR

f) Zero and full scale current calibration for CURRENT MONITOR

The main chassis frame of the power supply is constructed from cold-rolled steel, as is the per­forated wrap-around cover. Front panel material is aluminum (Refer to FIG. 1-3 for finish).

JQE 27274 092611 1-1

1.4 ACCESSORIES

a) RACK ADAPTOR (for two units); Kepco Model RA 24. Fits standard EIA rack-dimen-

sions.

b) FILLER PANEL, to cover empty slot if RA 24 is used for one unit only: Kepco Model RFP

24-2.

1.5 SPECIFICATIONS

TABLE 1-1. JQE 25-20MVPY-27274 SPECIFICATIONS

SPECIFICATION RATING/DESCRIPTION CONDITIONS/NOTES

A-C Input Voltage nominal 115/230V a-c Single Phase.

range 105-125/210-250V a-c Selectable by changing internal

jumpers

Frequency nominal 50/60 Hz

Range 47-63 Hz

Input Current 11A a-c max. @ 125V a-c

6A a-c max. @ 250 a-c

Isolation to Chassis 500V d-c or peak Max. between either output ter-

minal and Chassis

Leakage Current 115 Va-c 5

Insulation coordination Input Installation Category II,

Output Installation Category II,

Pollution degree 2

Type of stabilizer Linear, 1-quadrant, rectangular V-I

Output Voltage
(Voltage mode)

Temperature coefficient 0.01% of nominal/°C 0 to +50°C. FS

Output Current
(Current Limit mode)

Temperature coefficient 0.02% of nominal/°C 0 to +50°C. FS

(1) Zero and FS (full scale) calibration adjustments accessible through top cover.
(2) FS (full scale) calibration adjustment accessible through top cover.

Range 0 to +25V d-c Using a 10-turn front panel

Resolution 0.05% of nominal

Accuracy 0.1% of nominal

Source effect 0.005% of nominal For 105-125 / 210-250V a-c

Load effect 0.005% of nominal No load- Full load

Time effect 0.05% of nominal 8 Hrs, FS

Ripple & noise 0.2 mVrms / 10mVp-p FS

Range +0.1 to +20A d-c Using a 10-turn front panel

Resolution 0.05% of nominal

Accuracy 0.1% of nominal

Source effect 0.01% of nominal For 105-125 / 210-250V a-c,

Load effect 0.05% of nominal Short circuit - Full load

Time effect 0.05% of nominal 8 Hrs, FS

Ripple & noise 0.05% of nominal rms/

µArms / 50 µAp-p Between output and Chassis

For TN power system

Overvoltage Category II

Max. 500 Vd-c or peak between

Overvoltage Category II

0.2% of nominal p-p

output and Chassis

potentiometer. Factory default
setting is 0V.

(1)

, full load

(1)

, full load

(1)

, full load, local sensing

potentiometer. Factory default
setting is 20A

short circuit at output

(2)

put

(2)

FS
value

, short circuit at out-

(2)

, full load

, short circuit, nominal

1-2 JQE 27274 092611

TABLE 1-1. JQE 25-20MVPY-27274 SPECIFICATIONS (Continued)

SPECIFICATION RATING/DESCRIPTION CONDITIONS/NOTES

Output Power 500W

Output Impedance Voltage Mode 63

Current Mode 25KOhms / 5.8 mF

Voltage Recovery Time 50

Voltage Overshoot N/A For turn on/turn off: above 25%

Current Recovery Time Constant (R

Protections Input Overcurrent All protections trip the input circuit breaker

Pass element Heatsink

Overtemperature

Output Overvoltage (OVP)

Overvoltage Protection Adjustable Range 5% to 130% of nominal output voltage

Threshold Accuracy 0.5V

Adjustable triggering delay 25 ±5 to 180 ± 40

Triggering time 5 - 10

Display Analog meters for Output Voltage and

Isolated Remote
monitoring signals
for Output Voltage
and Current

Output impedance 100 Ohms

Remote voltage sensing Kelvin connection for remote sensing with

Remote programming
time

Cooling Air forced cooling, using an a-c fan with low

Operating temperature range 0 to +50°C

Storage temperature
range

Altitude Operating from sea level to 10,000 feet

(1) Zero and FS (full scale) calibration adjustments accessible through top cover.

Range 0 to +10V

Accuracy 0.1% for voltage monitoring,

Output current 5 mA max.

Output Ripple voltage monitor: 0.5mVrms in voltage mode

current monitor: 1.0mVrms in current mode

max 1.0V per load-wire

Depends on load value, internal output
capacitor (5.8 mF) and current limit setting

noise non-metal blade

µOhms / 0.5 µH

µS max With load between No load and

)(C

load

to OFF.

)C

out

value

µSec Middle value as default.

µSec

Current, with 3% accuracy

(1)

for zero to nominal output

voltage and current

0.2% for current monitoring

-25 to +85°C

Full load, Output voltage in Volt­age mode.

of nominal setting; Below 25%:
negligible for load above 10% of
nominal.

= 5.8mF; With load between

out

full load and short circuit.

Factory default setting is maxi­mum value.

2-inch recessed panel meters,
one for output voltage, one for
output current

Monitoring signals are isolated
from power supply output termi­nals and chassis (500V
d-c max. or peak)

Intake from top, sides and bot­tom; needs at least 1 in. on top
and/or sides for cooling; exhaust
to rear

JQE 27274 092611 1-3

TABLE 1-1. JQE 25-20MVPY-27274 SPECIFICATIONS (Continued)

SPECIFICATION RATING/DESCRIPTION CONDITIONS/NOTES

Dimensions 8.344" x 5.219" x 17.584" (WxHxL) See Mechanical outline drawing

Figure 1-1 for details

Weight 33 lbs

Front panel controls Voltage and Current limit-Type: 10-turn

potentiometers

Connections AC input power cable, with 3-wire safety

line cord and polarized plug

Chassis grounding connection

±Output power terminals

Sensing, monitoring, controlling terminal

block

Monitor signals connector

(Dsub type, 9-pin receptacle)

1.6 SPECIFICATIONS, MECHANICAL

a) DIMENSIONS AND FINISH: Refer to Mechanical Outline Drawing, Figure 1-1.

b) BAIL: A retractable bail is provided for convenient bench operation of the power supply.

1-4 JQE 27274 092611

OVP DELAY

ADJ.

OVP ADJ.

2953-2

O

O

O

S

S

R

R

S

F

F

R

S

1

E

E

-

F

E

F

Z

Z
N
O
M
V

3

N

N

Z

5

N

O

O

9

T

T

2

O

M

M

U

U

T

O

O

V

C

M

U

I

E

O

C

E

JQE 27274 092611 1-5/(1-6 Blank)

FIGURE 1-1. MECHANICAL OUTLINE DRAWING

SECTION 2 - INSTALLATION

2.1 UNPACKING AND INSPECTION

This instrument has been thoroughly inspected and tested prior to packing and is ready for
operation. After careful unpacking, inspect for shipping damage before attempting to operate.
Perform the preliminary operational check as outlined in PAR. 2.5. If any indication of damage is
found, file an immediate claim with the responsible transport service.

2.2 TERMINATIONS

a) Front Panel: Refer to Figure 2-1 and Table 2-1.

FIGURE 2-1. FRONT PANEL CONTROLS AND INDICATORS, JQE SPECIAL MODELS

TABLE 2-1. FRONT PANEL CONTROLS AND INDICATOR FUNCTIONS

CONTROL OR INDICATOR FUNCTION

AC POWER CIRCUIT BREAKER Turns a-c power to unit ON or OFF and protects power supply input circuitry.

AC PILOT LIGHT Energizes when unit is turned ON and a-c power is applied to the unit.

VOLTMETER Monitors output voltage 0 to EO max.

AMMETER Monitors output current 0 to IO max.

VOLTAGE CONTROL Adjusts output voltage from 0 to EO max.

CURRENT LIMIT CONTROL Adjusts current limit A from 0.5% to 100% of IO max.

JQE SPECIAL SVC 092611 2-1

b) Rear Panel: Refer to Figure 2-2 and Table 2-3.

FIGURE 2-2. REAR PANEL TERMINATIONS, JQE SPECIAL MODELS

TABLE 2-2. REAR PANEL TERMINATION FUNCTIONS

INDEX NO.

(FIGURE 2-2)

1 Rear Barrier Strip (TB

2 + OUTPUT Positive output power terminal (binding post)

3 – OUTPUT Negative output power terminal (binding post)

4 CHASSIS GROUND

5 A-C INPUT 3-wire safety line cord with a NEMA 5-15P plug.

6 MONITOR PORT Allows remote analog monitoring of the output voltage and current.

7 REAR BARRIER

TERMINATION FUNCTION

Sense/Monitoring/programming Terminals

501)

CONNECTION

STRIP LINKS

(1) +OUTPUT MONITOR
(2) +SENSE
(3) –OUTPUT MONITOR
(4) –SENSE
(5) INTERNAL VOLTAGE CONTROL
(6) NULL JUNCTION ((Voltage Loop Amplifier input)
(7) REFERENCE RESISTOR 1
(8) REFERENCE VOLTAGE
(9) REFERENCE RESISTOR 2

Permits either the positive or negative output of the power supply to be grounded. Also
permits safety earth-ground connection of JQE Special chassis.

Pin 1: Current Monitor; Pin 6: Current Monitor Return
Pin 2: Voltage Monitor; Pin 7: Voltage Monitor Return
NOTE: The returns of the monitoring signals for voltage and current are common by

default. They can become independent by removing the jumper at test point TP1.

JQE Specials are shipped with five links in place to establish front panel operation with
local sensing. One link connects: +OUT MON and +S, one link connects: –OUT MON
and -S, two links connect: V CTRL, NULL and REF R1, and one link connects: REF V
and REF R2.

2-2 JQE SPECIAL SVC 092611

c) Internal Adjustments and Calibrations: Refer to Figure 2-3 and Table 2-3.

OVP DELAY ADJ. (A4 R(C) 403)

OVP ADJ. (A4 R415)

V ZERO

MON

MONV

FS

MON

C

ZERO

C

MON

FS

OUT

ZERO

E

OUTE

FS

OUT

FS

I

FIGURE 2-3. LOCATION OF INTERNAL ADJUSTMENTS

TABLE 2-3. INTERNAL ADJUSTMENTS

REFERENCE

DESIGNATION

A4R(C)403 OVP DELAY ADJ Adjusts delay time of Overvoltage Protection. PAR. 4.5

A4R415 OVP ADJ Adjusts Overvoltage Protection level. PAR.4.5

A1R45 V. MON ZERO Calibrates zero for the voltage monitor signal. PAR. 4.3.3

A1R39 V. MON FS Calibrates full scale for the voltage monitor signal. PAR. 4.3.7

A1R53 C. MON ZERO Calibrates zero for the current monitor signal. PAR. 4.3.4

A1R47 C. MON FS Calibrates full scale for the current monitor signal. PAR. 4.4.3

A1R3 E

A1R16 E

A1R28 I

CONTROL PURPOSE

ZERO Calibrates zero for output voltage. PAR. 4.3.2

OUT

FS Calibrates full scale for output voltage in Voltage mode. PAR. 4.3.5, 4.3.6

OUT

FS Calibrates full scale for output current in Current mode. PAR. 4.4.2

OUT

2.3 AC INPUT REQUIREMENTS

This power supply is normally supplied for operation on a single phase, nominal 115V AC line.
For conversion to 230V AC line operation, refer to FIG. 2-4. Remove the two wire jumpers
between transformer terminals indicated. Re-connect one (1) jumper between terminals indi­cated. Do not change any other wiring on the transformer.

ADJUSTMENT

PROCEDURE

JQE SPECIAL SVC 092611 2-3

FIGURE 2-4. CONVERSION TO 230V AC LINE OPERATION

2.4 COOLING

The power transistors and rectifiers in this power supply are maintained within their operating
temperature range by means of a high efficiency heat-sink assembly, coded by an internal fan.
SIDE PANEL OPENINGS AND THE TOP OF THE CASE MUST BE KEPT CLEAR FROM
OBSTRUCTIONS TO INSURE PROPER AIR CIRCULATION. Periodic cleaning of the interior
of the power supply is recommended. If the power supply is rack mounted, or installed into con­fined spaces, care must be taken that the ambient temperature does not rise above the limit
specified (Refer to Section 1).

2.5 PRELIMINARY OPERATIONAL CHECK

A simple operational check after unpacking and before equipment installation is advisable to
ascertain whether the power supply has suffered damage resulting from shipping. Refer to Fig­ures 2-1 and 2-2 for location of operating controls and electrical connections.

1. Connect power supply to 115V AC line or refer to paragraph 2.3 for 230V AC operation if
required.

2. Verify that the following links are installed at the rear panel (see Figure 2-2) and that the con­nection is tight:
TB501 between terminals (1) and (2)
TB501 between terminals (3) and (4)
TB501 between terminals (5), (6) and (7)
TB501 between terminals (8) and (9)

3. Turn CURRENT LIMIT CONTROL full clockwise. Turn VOLTAGE CONTROL fully counter­clockwise.

4. Connect a DVM between terminals (2) and (4) of TB501 at the rear panel.

5. Turn AC POWER circuit breaker “on.” The AC PILOT LIGHT should be energized. Slowly
turn VOLTAGE CONTROL clockwise and verify the front panel voltmeter shows a gradual
increase of the output voltage up to E
fully clockwise, the DVM voltage reads E

6. Check the “crowbar” action of the overvoltage protection by adjusting the output voltage to
E

nominal using the front panel VOLTAGE control. Through the access hole in the top

O

cover, slowly adjust the OVP ADJ pot counterclockwise until the input circuit breaker trips.

2-4 JQE SPECIAL SVC 092611

nominal. Verify that when the VOLTAGE control is

O

nominal (±0.1% EO nominal).

O

Turn the OVP ADJ pot 1/4 turn clockwise. Turn AC POWER circuit breaker “on” and verify
that the unit stays on.

7. Turn AC POWER circuit breaker “off.” Place a 4-terminal precision shunt across the power
output terminals (2, 3 Figure 2-2). Connect the DVM to the shunt’s sensing terminals (DVM
return to the sensing terminal of the shunt that is connected to –OUTPUT power terminal at
TB501). Turn CURRENT LIMIT CONTROL fully counterclockwise.

8. Turn AC POWER circuit breaker “on.” Verify that DVM reading corresponds to 0.5% of nom­inal output current (0.1A ±5mA) using the formula below. Slowly turn front panel CURRENT
LIMIT CONTROL clockwise and observe the gradual increase in output current at the front
panel ammeter. Check that at the full clockwise position of the CURRENT LIMIT CONTROL
the DVM corresponds to the nominal current value (20A ± 20mA).

NOTE: Use the following formula to obtain output current I

IO(Amperes)

V

---------------------------------------------=
R

SHUNT

DVM

(Volts)

(Ohms)

from the DVM voltage readings:

O

2.6 INSTALLATION (REFER TO FIGURE 1-1, OUTLINE DRAWING)

The JQE specials may be used as a bench-operated instrument. A retractable “bail” is provided
to lift the power supply front to a convenient viewing and operating angle. If the supply is to be
rack-mounted, the bail, the two rear feet and the side handles must be removed.

For all installations into confined spaces, care must be taken that the temperature immediately
surrounding the unit does not exceed the maximum specified ambient temperature (50°C).

2.7 GROUNDING

AC GROUND. The power supply is equipped with a 3-wire safety line cord and polarized plug.
The third (green) wire in the line cord is connected to the chassis and the case of the unit.

WARNING

For safe operation It is recommended that the rear panel stud marked be
connected to the appropriate earth ground.

DC GROUND. The DC output is isolated from the AC power line and from any direct connection
to chassis or ground. The maximum voltage that can be supported between either output termi­nal and ground or chassis is 500V DC plus the maximum output voltage of the power supply.
Either side of the output may be grounded. The rear panel chassis ground connection (4, Figure
2-2) can be used to reference the output to ground.

JQE SPECIAL SVC 092611 2-5/(2-6 Blank)

SECTION 3 - OPERATION

3.1 STANDARD POWER SUPPLY OPERATION, LOCAL CONTROL

3.1.1 GENERAL

The Power Supply is shipped from the factory with five (5) removable jumper links in place at
the rear barrier strip TB501 as shown in FIG. 3-1, THESE LINKS MUST BE IN PLACE AND
SECURED TIGHTLY for standard local operation. Loose terminal links or wires at the barrier
strip will cause malfunction of the power supply.

3.2 LOAD CONNECTION

The load may be connected in either of the two ways illustrated (Figure 3-1).

3.2.1 LOCAL ERROR SENSING (SEE FIGURE 3-1A.)

This type of load connection is recommended for constant load applications. Install the links
between terminals (1) and (2) and between terminals (3) and (4) of TB501 at the rear panel.
Load connecting wires should be as heavy as practicable, since load wire voltage drops will
degrade regulation performance, hence the recommendation for constant load applications.
Twisting of load wires will help to preserve the low output impedance as well as reduce the cou­pled and radiated noise of the power supply.

LOAD CONNECTION,

DEFAULT JUMPER LINKS INSTALLED,

WITHOUT REMOTE ERROR SENSING

-OUTPUT +OUTPUT +OUTPUT-OUTPUT

FIGURE 3-1. LOAD CONNECTION SHOWING A FLOATING LOAD

TWISTED

PAIR

LOAD CONNECTION

WITH REMOTE ERROR SENSING

(KELVIN CONNECTION)

TWISTED

PAIR

#22 AWG
TWISTED

PAIR

JQE SPECIAL SVC 092611 3-1

3.2.2 REMOTE ERROR SENSING (SEE FIGURE 3-1B.)

Remove the links between terminals (1) and (2) and between terminals (3) and (4) of TB501 at
the rear panel. Specified regulation performance DIRECTLY AT THE LOAD requires the use of
remote error sensing. A twisted, pair of wires from the sensing terminals directly to the load will
compensate for load wire voltage drops up to 1.0 volt per wire (Refer to Figure 3-1B). Observe
polarities: for example, the positive sensing wire (from TB 501 terminal 2) goes to the positive
load terminal (connected to + OUTPUT terminal).

To keep the DC voltage drop in the load connecting wires to a minimum, and to preserve the
dynamic characteristics of the power supply (AC stability, output impedance and recovery time),
load wires should be as short as possible and as large in diameter as practicable, rated at least
for nominal output current. Error sensing leads should be #22 AWG and as short as possible.
Both lead pairs should preferably be tightly twisted. For minimum ripple and noise pick-up, the
error sensing leads may be shielded. The shield should be returned to the ground point of the
JQE Special.

3.2.3 GROUNDED LOAD CONNECTION

If the load has one end connected to EARTH-GND, then connect the load termination con­nected to EARTH-GND to +OUTPUT at the rear panel for better output noise performance (see
Figure 3-2A). For this configuration the voltage across the load will be negative with respect to
chassis GND.

If the load is floating, but it is desired to have the JQE having the output with a certain polarity
with respect to chassis GND, connect locally, either –OUTPUT terminal to chassis GND for a
positive output voltage referenced to chassis GND (see Figure 3-2B), or connect +OUTPUT ter­minal to GND for a negative output voltage referenced to chassis GND (see Figure 3-2C).

GROUNDED LOAD CONNECTION,

FOR A NEGATIVE OUTPUT

WITHOUT REMOTE ERROR SENSING

+OUTPUT-OUTPUT

TWISTED

PAIR

NEGATIVE OUTPUT

REFERENCED TO CHASSIS

WITHOUT REMOTE ERROR SENSING

-OUTPUT +OUTPUT

TWISTED

PAIR

POSITIVE OUTPUT

REFERENCED TO CHASSIS

WITHOUT REMOTE ERROR SENSING

TWISTED

PAIR

+OUTPUT-OUTPUT

FIGURE 3-2. GROUNDED LOAD CONNECTIONS

3-2 JQE SPECIAL SVC 092611

3.3 OUTPUT ADJUSTMENT

Once the load is connected to the output terminals of the power supply as described in the pre­vious paragraphs, the operating voltage may be adjusted to the desired value by turning the
front panel VOLTAGE potentiometer and observing the front panel VOLTMETER. The output
voltage range is zero to 100% of the nominal value.

Use the front panel CURRENT LIMIT potentiometer to control current limit.

The CURRENT LIMIT value may be set to intermediate values, as desired, by first turning the
AC POWER circuit breaker to the “off” position and then placing a short circuit across the out­put. Turn AC POWER circuit breaker “on.” Now the required operating current is adjusted by
turning CURRENT LIMIT to the value needed. For a more precise current limit adjustment use a
4-terminal shunt connected at the output as specified in PAR. 2.5 step 7. The range for current
limit is 0.5% to 100% of I
the short is removed from the output, the voltage can be set: either output voltage for voltage
mode, or voltage limit for current mode.

With the OVP ADJ potentiometer set fully clockwise (factory default setting), set the output volt­age as described above. Turn the OVP ADJ potentiometer slowly counterclockwise, until the
power supply output “crowbars,” indicated by the output voltage going to zero and the circuit
breaker tripping. Turn the OVP ADJ potentiometer 1/4 turn clockwise. Adjustment too close to
the operating voltage may lead to spurious triggering, especially if the “delay” adjustment is set
for maximum sensitivity. Adjust the OVP DELAY ADJ potentiometer if required. This control is
factory adjusted to the middle of the adjustment range. It needs re-adjustment only if extremely
sensitive loads must be triggered in the shortest time possible and if some spurious triggering
can be tolerated. Now the load can be connected to the power supply and operation can com­mence.

nominal. Turn off the unit and remove the short-circuit or shunt. After

O

3.4 INTRODUCTION TO REMOTE PROGRAMMING

3.4.1 GENERAL

A few general remarks may be in order to familiarize the user of this equipment with the termi­nology and basic equations pertaining to remote programming of Kepco Power Supplies. Elec­trically, the power supply, consists of the unregulated DC source (E
the DC error amplifier (A

) and a comparison circuit which resembles a four-arm electrical

V

bridge. (Refer to Figure 3-3). The elements of the bridge are arranged to produce a virtual zero
at the amplifier input when the bridge circuit is at balance (V
voltage to change in relation to the reference voltage (E
means of negative feedback and the amplifier, tends to correct the output voltage towards resto­ration of bridge balance.

), the pass element (EP),

U

= 0). Any tendency for the output

AA'

) creates an error signal (E) which, by

r

JQE SPECIAL SVC 092611 3-3

= BRIDGE CURRENT

NULL JUNCTION

REFERENCE

RESISTOR

VOLTAGE

ERROR

AMPLIFIER

REFERENCE

VOLTAGE

VOLTAGE
CONTROL
RESISTOR

UNREGULATED

SOURCE

PASS - ELEMENT

INTERNAL COMMON POINT

OUTPUT

VOLTAGE

FIGURE 3-3. COMPARISON BRIDGE (SIMPLIFIED) FOR VOLTAGE MODE

A similar bridge representing power supply operation in CURRENT LIMIT mode is shown in Fig­ure 3-4

= BRIDGE CURRENT

NULL JUNCTION

REFERENCE

RESISTOR

CURRENT FEEDBACK

RESISTOR

CURRENT

ERROR

AMPLIFIER

UNREGULATED

CURRENT CONTROL

VOLTAGE REFERENCE

SOURCE

PASS - ELEMENT

INTERNAL CURRENT
SENSING RESISTOR

INTERNAL COMMON POINT

OUTPUT

CURRENT

LIMIT

LOAD

FIGURE 3-4. COMPARISON BRIDGE (SIMPLIFIED) FOR CURRENT MODE

3-4 JQE SPECIAL SVC 092611

3.4.2 EQUATIONS SHOWING THE OPERATION OF THE KEPCO BRIDGE

The following relationships govern the operation of the Kepco Bridge at balance in voltage
mode, i.e., with V

E

R

O

VC

------------=
R

r

=

b

(1)

(2)

-------­E

r

E

r

------I
R

r

E

=

OIbRVC

= 0.

AA’

(3)

Where: EO = Output Voltage

E

= Reference Voltage

r

= Reference Resistance

R

r

R

= Voltage Control Resistance

VC

= Bridge Control Current

I

b

The ratio of Ohms control - resistance needed per volt output is termed the “CONTROL
RATIO.“For local control the ratio is determined by the front panel VOLTAGE control potentiom­eter value and tolerance.

As can be seen from equation (1), the output voltage E

can be controlled by varying any one of

O

the three quantities. Rewriting equation (1) we have

E

r

The ration constitutes the bridge control current I

Therefore we can write E

Making I
E

O

a precision quantity establishes a precise programming ratio, so that the accuracy of

b

is solely dependent upon R

------

E

O

E

r

-----­R

r

RVC×=

R

r

(Eq. (2).

b

= IbR

O

(Eq. (3).

VC

This mode of operation is referred to as Resistance Program-

VC.

ming and is covered in detail in PAR. 3.6.

NOTE: For all programming and adjustment components, use high quality, wire-wound resis-

tors with a T.C. of 20 ppm or better.

Similar relationships can be described for operation in Current Limit mode. The following rela­tionships govern the operation of the Kepco Bridge at balance in current mode, i.e., with VAA’ =

0.

IORSK

----------------------

I

=

O

I

=

O

E

---------------------­KSRSR

--------------­KSR

R

S

CF

(4)

-----------=

R

CF

CF

R

r

(5)

E

r

r

E

r

-----­R

S

(6)

r

r

R

Where: EO = Output Voltage

= Reference Voltage

E

r

R

= Reference Resistance

r

= Bridge or Control Current

I

b

K

= Current Sensing Amplification Factor

S

= Current Sensing Resistor

R

S

R

= Current Feedback Resistor

CF

R

CF

---------------

I

=

O

JQE SPECIAL SVC 092611 3-5

KSR

I

b

S

(7)

R

CF

The ratio of termed the “CONTROL RATIO,“ gives the current (in mA) needed to obtain

one Ampere of output current where R

--------------­KSR

S

is in Ohms and RCF is in KOhms.

S

3.5 GENERAL RULES FOR REMOTE PROGRAMMING

All remote programming applications require the observance of a few basic rules to insure
proper functioning of the power supply in the particular mode of operation selected. These rules
should be remembered before each application, and especially if malfunctioning of the program­ming set-up is experienced.

3.5.1 GROUNDING

Ground loops due to multiple and indiscriminate grounding of various equipment are the cause
of the majority of complaints about “high ripple or noise.” They can be easily avoided by ground­ing the system (power supply, load, measuring equipment) at one point only to which all
shielded cables and equipment cases are connected. If possible, one side (preferable the posi­tive one) of the power supply output should be grounded for best possible noise-related perfor­mance.

3.5.2 CONNECTIONS

All external connections, especially the rear barrier strip terminal screws, must be tight. Series
malfunctions may be caused by open feedback loops, error sensing lines or programming con­nections.

3.5.3 PROGRAMMING RESISTORS

Programming resistors should be high quality wirewound units with temperature coefficients of
20 parts per million or better. Their wattage rating must be at least 10 times the actual power
dissipated. Although the control current through these resistors is only 1 mA, an error current
spike exists when programming large voltage excursions. The peak of the current is limited by
the internal 500 Ohm resistor and depends upon the magnitude of output voltage swing. The
time constant is determined by the internal 500-Ohm resistor and the unit’s output capacitance
given in Table 1-1 for current mode.

3.5.4 EXTERNAL SWITCHING

If step-switch devices are used in resistance programming, they must be of the “make before
break” variety to avoid programming infinity. Programming resistors must have a voltage rating
at least equal to the maximum output voltage of the power supply.

3.6 OUTPUT VOLTAGE PROGRAMMING WITH EXTERNAL RESISTANCE

The output voltage of the Power Supply may be controlled remotely by an external resistance,
replacing the built-in voltage control resistance which is disconnected at the rear barrier strip;
this is accomplished by removing the link between terminals 5 and 6 at terminal block TB501 at
the rear panel. Refer to Figure 3-5 and install an external variable resistance between terminals
4 and 6 at terminal block TB501 at the rear panel. For full calibration capabilities, choose the
variable external full scale resistance value to be equal to the internal R
control ratio KOhms/Volt, first perform Full Scale calibration, then measure the current flowing
through the external resistance; the reciprocal of measured current is the control ratio KOhms/

value. To obtain the

VC

3-6 JQE SPECIAL SVC 092611

Volt which can then be used to program a specific output voltage based on a specific resistance
of the external variable resistor.

To set an output voltage using an external programming resistor, proceed as follows:

1. Determine value of programming resistor(s) for output voltage desired.

2. Using two-wire, shielded cable, connect the chosen resistors to terminals 4 and 6 at ter­minal block TB501 on the rear panel. Connect the shield to the GND terminal of the JQE
Special.

3. The output voltage (Volts) will be I

I

------------------------------------------------------=

b

R

VC ext FS (Kohms)

E

Onom

V〈〉

(mA) x RVC (KOhms), (where

b

FIGURE 3-5. REMOTE RESISTANCE PROGRAMMING (VOLTAGE MODE)

3.7 CONSTANT CURRENT OPERATION

JQE special power supplies will deliver constant current depending on the output voltage and
output current limit settings as well as the load value. In constant current operating mode, the
voltage comparison bridge is interconnected with the internal current sensing resistor, R
current control, R
way, an adjustable constant load current is obtained. Characteristic of the constant current sup­ply is ability to change its output voltage automatically in order to maintain a constant current
through a range of possible load resistances. The range of output voltage that the supply can
deliver and simultaneously maintain constant current, is referred to as the “COMPLIANCE
VOLTAGE.”

JQE SPECIAL SVC 092611 3-7/(3-8 Blank)

(as shown in Figure ) to maintain a constant voltage drop across RS. In this

CC

S

, and a

SECTION 4 - CALIBRATION

4.1 GENERAL

It is recommended that both output voltage and output current limit calibrations be performed in
sequence, however it is permissible to do only one if the other is known to be calibrated.
Required test equipment is listed in PAR. 4.2. See Table 2-3 and Figure 2-3 for descriptions and
locations, respectively, of the calibration adjustments.

4.2 TEST EQUIPMENT REQUIRED

The following test equipment is required to perform the calibration procedures in this section.

a). Resistive load, variable, with ON/OFF and SHORTING SWITCH and capable of dissi-

pating the full output power of the unit under test.

b). Digital DC voltage monitor (DVM), digital voltmeter, or power supply analyzer.

c). External Programming Resistor used for FS Remote Calibration:

value: 30.1KOhms, tolerance: 0.01%, 0.5W.

d). Precision Current Sensing Resistor (Shunt): 0.01 Ohm, ±0.1%, 100W, 20ppm/°C, with

the value measured to 0.01% accuracy.

e). AC ripple monitor, sensitivity better than 1 mV. Ballantine Model 302C. or Hewlett Pack-

ard Model 400H or Oscilloscope, vertical sensitivity better than 0.1 mV/div.

4.3 OUTPUT VOLTAGE CALIBRATION

The output voltage calibration consists of the following calibration procedures which must all be
performed in sequence: Pre-calibration Setup (PAR 4.3.1), Zero Output Voltage (PAR 4.3.2),
Zero Voltage Monitor (PAR 4.3.3), Zero Current Monitor (PAR 4.3.4), Local Full Scale (FS) Out­put Voltage (PAR 4.3.5), Remote Full Scale (FS) Output Voltage (PAR 4.3.6) and Full Scale (FS)
Voltage Monitor (PAR 4.3.7).

4.3.1 VOLTAGE PRE-CALIBRATION SETUP

Turn the power supply off and verify the following:

1. At the rear panel links between terminals 1 and 2, terminals 3 and 4, terminals 5, 6 and 7
and terminals 8 and 9 on TB501 are installed and securely tightened

2. Turn front panel I

control to the full clockwise position.

lim

3. Turn front panel VOLTAGE control to the full counterclockwise position.

4. Turn the OVP adjustment (see Figure 2-3) to full clockwise position.

5. Verify that no load is connected to the output.

JQE SPECIAL OPR 092611 4-1

4.3.2 ZERO OUTPUT VOLTAGE CALIBRATION

Zero Output voltage is calibrated for either the local front panel VOLTAGE control (PAR 4.3.2.1)
or an external resistance used for remote programming of output voltage (4.3.2.2).

4.3.2.1 ZERO OUTPUT VOLTAGE (LOCAL PROGRAMMING) CALIBRATION

NOTE: In effect only for local operation.

The following procedure calibrates the front panel VOLTAGE control for 0V output when set to
minimum. Due to slight resistance present even when the VOLTAGE control is set to minimum,
this calibration may not be accurate in remote mode where an external resistance is used for
remote programming of the output (see PAR. 4.3.2.2 if using remote programming).

1. Connect DVM between terminals 2 and 4 of TB501 with the DVM reference terminal con­nected to terminal 4.

2. Turn ON the unit, and allow unit to operate for 10 to 15 minutes before proceeding.

3. Adjust E

ZERO potentiometer (accessible through top cover) until output voltage reads

OUT

0V (tolerance: 0 mV to +3 mV).

4.3.2.2 ZERO OUTPUT VOLTAGE (REMOTE PROGRAMMING) CALIBRATION

NOTE: In effect only for remote operation.

The following procedure calibrates the output for 0V when using an external resistance for
remote programming of the output. See PAR. 4.3.2.1 if using front panel VOLTAGE control to
program the output.

1. Remove the link between terminals 5 and 6 of TB501 at the rear panel.

2. Connect the External Programming resistor (see PAR. 4.2) between terminals 4 and 6 of
TB501 at the rear panel. Place a temporary short circuit across the External Programming
resistor.

3. Connect DVM between terminals 2 and 4 of TB501 with the DVM reference terminal con­nected to terminal 4.

4. Turn the unit on and allow unit to operate for 10 to 15 minutes before proceeding.

5. Adjust E

ZERO potentiometer (accessible through top cover) until output voltage reads

OUT

0V (tolerance: 0 to +3mV).

4.3.3 ZERO VOLTAGE MONITOR CALIBRATION

This calibration procedure should follow either PAR 4.3.2.1 for local voltage control or PAR.

4.3.2.2 for remote control.

1. At the rear panel. connect DVM between pin 2 and pin 7 (DVM return) of the MONITOR
PORT connector.

2. Adjust V.MON ZERO potentiometer (accessible through top cover) until DVM reads 0V (tol­erance: 0 to +1mV).

4-2 JQE SPECIAL 092611

4.3.4 ZERO CURRENT MONITOR CALIBRATION

1. At the rear panel, connect DVM between pin 1 and pin 6 (DVM return) of the MONITOR
PORT connector.

2. Adjust C.MON ZERO potentiometer (accessible through top cover) until DVM reads 0V
(tolerance: 0 to +1mV).

4.3.5 LOCAL FULL SCALE (FS) OUTPUT VOLTAGE CALIBRATION

NOTE: In effect only for local operation.

1. Set front panel VOLTAGE control to the full clockwise position.

2. At the rear panel connect DVM between terminals 2 and 4 of TB501 with the DVM refer­ence terminal connected to terminal 4.

3. Adjust E

FS potentiometer (accessible through top cover) until output voltage reads

OUT

25V (tolerance: ±5mV).

4.3.6 REMOTE FULL SCALE (FS) OUTPUT VOLTAGE CALIBRATION

NOTE: In effect only for remote operation.

1. Turn the JQE special power supply off.

2. Remove the link between terminals 5 and 6 of TB501 at the rear panel.

3. Connect the External Programming resistor required for FS calibration (see PAR. 4.2)
between terminals 4 and 6 of TB501 at the rear panel.

4. Turn the unit on and adjust E

FS potentiometer (accessible through top cover) until out-

OUT

put voltage reads 25V (tolerance: ±5mV).

4.3.7 FULL SCALE (FS) VOLTAGE MONITOR CALIBRATION

This calibration procedure should follow either PAR 4.3.5 for local voltage control or PAR. 4.3.6
for remote control.

1. At the rear panel. connect DVM between pin 2 and pin 7 (DVM return) of the MONITOR
PORT connector.

2. Adjust V.MON FS potentiometer (accessible through top cover) until DVM reads +10V (tol­erance: ±2mV).

JQE SPECIAL OPR 092611 4-3

4.4 OUTPUT CURRENT LIMIT CALIBRATION

Output current limit calibration consists of the following procedures: Pre-Calibration setup (PAR.

4.4.1), Full Scale (maximum) Output Current Limit (PAR. 4.4.2), Full Scale Current Monitor
(PAR. 4.4.3) and Minimum Output Current Check (PAR. 4.4.4).

4.4.1 CURRENT LIMIT PRE-CALIBRATION SETUP

1. Current measurements are made by measuring the voltage drop across the sense resistor
(see PAR. 4.2) and then converting the result to current using the following formula. It is
critical that the actual value of the current sensing resistor be measured accurately.

R

= the measured value of the current sensing resistor in ohms (0.01% accuracy).

SENSE

Calculated output current [Amperes] = (

V

DVM

[Volts])/R

SENSE

[Ohms]

2. Turn the JQE special power supply off and, if connected, remove the external remote pro­gramming resistor from terminals 4 and 6 of TB501 at rear panel.

3. Install link between terminals 5 and 6 of TB501 at rear panel.

4. Turn front panel I

control to the full clockwise position.

lim

5. Turn front panel VOLTAGE control to the full clockwise position.

6. Connect precision 4-terminals Current Sensing Resistor (Shunt) (see PAR 4.2) across the
output, between +OUTPUT and –OUTPUT terminals at the rear panel.

7. Connect the DVM to the Shunt's sensing terminals with the DVM reference terminal con­nected to the terminal closest to the –OUTPUT terminal at rear panel. Use the Shunt mea­sured value to correct the Output Current DVM readings.

8. Turn the unit on and allow unit to operate for 10 to 15 minutes before proceeding.

4.4.2 FULL SCALE (MAXIMUM) OUTPUT CURRENT LIMIT CALIBRATION

Adjust I

FS potentiometer (accessible through top cover) for output current limit of 20A

OUT

±5mA.

4.4.3 FS CURRENT MONITOR CALIBRATION

1. At the rear panel, connect DVM between pin 1 and pin 6 (DVM return) of the MONITOR
PORT connector.

2. Adjust C.MON FS potentiometer (accessible through top cover) for DVM reading of +10V
±2mV.

4-4 JQE SPECIAL 092611

4.4.4 MINIMUM OUTPUT CURRENT CHECK

1. Adjust I

control to full counterclockwise position.

lim

2. Verify that output current is 0.1A ±10mA.

4.5 OVERVOLTAGE PROTECTION (OVP) TEST AND ADJUSTMENT

1. Use the VOLTAGE control at the front panel to set the output voltage to the desired voltage
as measured by either the front panel voltmeter or by an external DVM.

2. Turn OVP DELAY ADJ potentiometer (accessible through top cover) to approximately the
middle position (five turns from one end).

3. Slowly, turn the OVP ADJ potentiometer counterclockwise until the power supply circuit
breaker trips OFF. Then turn OVP ADJ potentiometer clockwise between 1/4 and 1/2 turn.

4. Turn on the JQE special power supply. The circuit breaker should not trip and the output
voltage, measured by either the front panel voltmeter or by the external DVM, should the
same as step 1 above.

NOTE: The OVP circuit causes the circuit breaker to trip and initiates the Output Crowbar, a

solid state switch (thyristor) across the output. Adjust OVP DELAY ADJ potentiometer
so that the circuit breaker does not trip while the unit is operating with your particular
load and application. To avoid tripping the circuit breaker unnecessarily, for example
upon encountering load transients, a compromise must be made between the follow­ing:

• Rapid OVP action (minimum tolerance for output overvoltage):
OVP DELAY ADJ set to full counterclockwise position and

• Maximum delay of OVP action (where some overvoltage is acceptable):
OVP DELAY ADJ set to full clockwise position.

5. Repeat steps 1 through 4 above for any desired operational output voltage above 5%
E

.

Onom

JQE SPECIAL OPR 092611 4-5/(4-6 Blank)

SECTION 5 - THEORY OF OPERATION

5.1 SIMPLIFIED DIAGRAM DISCUSSION

Referring to Figure 5-1, the Main Power Transformer and Auxiliary Power Transformer convert
the line voltage to the required levels needed to produce the d-c operating voltages for the Main
and Auxiliary Supplies after passing through the Rectifier and Filter stages. The main power
supply is in series with the pass elements and the Current Sensing Resistor (R
the output voltage.The main pass elements are changing their series resistance to keep the out­put constant: voltage in voltage mode or current in current limit mode. The necessary drive for
this change is produced by the driver circuit which, in turn, receives its command signals either
from the current error amplifier (CEA) or the voltage error amplifier (VEA).

In voltage mode the output voltage is constantly compared to the voltage reference source. In
current limit mode the output current, monitored by the current sensing resistor, is compared to
the current reference source. Any change, in either output voltage in voltage mode or current in
current limit mode, is amplified by the associated amplifier and transferred to the Diode-Gate
which feeds directly into the driver circuit which produces the needed drive signal for the main
pass elements (DRV/PE), thus either keeping the output voltage constant, or, if the signal from
the current limit amplifier is dominant, limiting the output current to the pre-adjusted value.

The voltage-current limit characteristic is rectangular in shape and the unit automatically
switches between voltage mode and current limit mode. The transition point between modes is
determined by the combination of power supply settings and load value.

) and produces

S

The Overvoltage Protection (OVP) is connected across the output sensing terminals of the
power supply. A portion of the output voltage is continuously compared to an internal reference.
If an overvoltage occurs, the SCR (CROWBAR) short-circuits the output immediately and trips
the input A-C circuit breaker. After removing the overvoltage condition, the A-C input circuit
breaker must be set to “on” to restore operation.

5.2 CIRCUIT DESCRIPTION

For the purpose of analysis, the circuitry of the JQE special power supplies may be divided into
several sections which are individually described below. The overall schematic diagram (Figure
7-7) and the detailed schematic diagrams (Figures 7-8 and 7-9) Illustrate the circuitry described
in this section.

5.2.1 A-C INPUT CIRCUIT.

A-C line power is introduced through the a-c input barrier-strip or a heavy-duty three-wire line
cord with safety plug. The use of a grounded a-c power outlet will automatically ground the
power supply chassis, since the third wire of the line cord is directly connected to the metal
chassis and case. Once the a-c power circuit breaker (CB101) is closed, the primary of the main
transformer (T201), the fan (B201) and the a-c pilot light (DS101) will be energized. The two pri­mary windings of the main transformer are either connected in parallel (for 115V a-c nominal line
voltage) or in series (for 230V a-c nominal line voltage). The a-c power circuit breaker (CB101),
aside from switching the a-c primary power, has the function of disconnecting the power supply
from the a-c line in case of input overloads, short circuits, heatsink overtemperature or output
overvoltage. CB101 has two sensing coils, one of which is always in series with one of the pri­mary windings on T201 (T2-T5), whether the main transformer is wired for 115V or for 230V a-c.
The second sensing coil of CB101 is in series with the secondary winding on T201 which gener­ates operating potential for the overvoltage protection circuit (T201-T6, T7). If an overload
occurs, due to either internal component failure or crowbar action of the voltage protector, the

JQE SPECIAL SVC 092611 5-1

coil is energized sufficiently to activate the trip mechanism of CB101, thus disconnecting the
power supply from the a-c line.

FIGURE 5-1. JQE SPECIAL POWER SUPPLY, SIMPLIFIED SCHEMATIC DIAGRAM

5-2 JQE SPECIAL SVC 092611

Since the primary coil of the AUXILIARY POWER TRANSFORMER (T202) is in parallel with the
secondary for the overvoltage protection circuit, any failure in the auxiliary circuits, reflecting
back to the primary of the auxiliary power transformer (T202) will also activate the sensing coil
of CB101 and shut down the power supply. A thermal sensing element (S301) is mounted to the
heatsink assembly (A3) to protect the series regulator transistors from overtemperature. If the
preset temperature on S301 is exceeded, its contact closes and energizes the sensing coil of
CB101, resulting once more In the tripping of the a-c power circuit breaker and subsequent
removal of the a-c input power from the power supply.

5.2.2 MAIN D-C SUPPLY

The main d-c power is derived from a center-tapped secondary winding on T201. A full-wave
rectifier circuit with silicon diodes (CR201, CR202) operates into a capacitor input filter (C201 or
C201/C202) which is paralleled by a bleeder resistor (R202). The main d-c supply delivers the
output current via the series regulator or pass-element.

5.2.3 PASS-ELEMENT SECTION

The pass element section varies in complexity according to the output voltage and current rating
of the particular JQE half rack model. The power silicon pass-transistors of the JQE are located
on high-efficiency heatsinks and are cooled by a fan (B201). These models have a single heat­sink assembly (A3) with NPN transistors. The number of transistors depends on the individual
model. The JQE Special has two Darlington structured branches in series, each having four
power transistors connected in parallel. The branch connected to the power supply output
(through the current sensing resistor) receives the control signal. The voltage across it is con­stant, equal to the Auxiliary Driver Power Supply value. The other branch, tied to raw d-c, sup­ports the difference between the input raw d-c value, and the sum of the output voltage and the
Auxiliary Driver Power Supply voltage. A power resistor is connected in parallel with this branch
to reduce the higher power dissipation across the power transistors.

However complex the pass-element section, for analytical purposes it can be reduced to a sin­gle pass-transistor. Electrically, this pass-element is part of a series circuit consisting of the
unregulated main d-c power supply, the external load and the pass-transistor. The output of the
power supply is kept constant, regardless of variations in the unregulated supply and/or load, by
changing the series resistance of the control element (the pass-transistor) in the described
series circuit. The main driver stages, in turn, receive their base signals from the pre-driver
stage (A1Q2).

5.2.4 VOLTAGE ERROR AMPLIFIER (VEA)

The main function of the voltage error amplifier A1IC1 (see Figure 7-8) is to amplify the d-c error
signal, derived from the comparison bridge, to a level suitable to pass the diode gate circuit and
drive the pre-driver stage A1Q2. The voltage error amplifier is a d-c coupled, high-gain opera­tional amplifier. The amplifier input may be disconnected from the internal comparison bridge
circuit, and programmed externally. Although the amplifier is used in the non-inverting configura­tion, a positive input signal will produce a negative power supply output with respect to the
“common” (plus sensing terminal +SENSE), since the pass-elements provide another signal
inversion. If a link is installed between TB501, terminals 5 and 6 (see Figure 7-7), the output
voltage is controlled by front panel VOLTAGE control R102. When the link between TB501, ter­minals 5 and 6 is removed, output voltage can be controlled by an external resistance con­nected across TB501, terminals 4 and 6.

JQE SPECIAL SVC 092611 5-3

The output voltage zero (offset) value can be calibrated using potentiometer A1R3, while the full
scale value can be calibrated using potentiometer A1R16. Both calibration potentiometers can
be accessed through a slot in the top cover.

5.2.5 CURRENT LIMIT CIRCUIT (CEA)

The differential input of the current sensing amplifier, A1IC3, is connected to the current sensing
resistor (R

= R203). The amplified voltage drop across the current sensing resistor is continu-

S

ously compared to the “current” reference voltage, set by the current limit control. As long as the
amplified voltage developed across R

(due to load current flow) is less than the preset refer-

S

ence level, the current limit amplifier will be biased to its inactive state and will not affect the out­put. If the output current increases however, the voltage drop across R
reference level set by the current limit control. The current limit amplifier will be activated and
produce a drive signal at the diode gate greater than the output of the voltage error amplifier,
thereby taking control away from the voltage error amplifier and transferring the power supply
into current limit mode. Since both the current limit amplifier and voltage error amplifier are cou­pled through the diode gate circuit to the pre-driver stage A1Q2, the amplifier with the lower out­put will control the pass transistors and therefore the output.

The minimum current limit is a fixed, non-zero value (0.1A), while the full scale current limit can
be calibrated using potentiometer A1R20, accessible though a slot in the top cover.

5.2.6 OVERVOLTAGE PROTECTION CIRCUIT AND CURRENT MONITOR

Input and output connections for the overvoltage protection circuit (VP) are made via a single
connector, P401/J407. The circuit receives a-c voltage derived from a secondary of the main
transformer (T201). The a-c is rectified by a conventional bridge rectifier (A4CR1), capacitor fil­tered by the input filter capacitor (A4C1) and shunt regulated by a 15V zener diode (A4CR3). A

6.5-Volt source, derived from the pre-regulated DC voltage by means of shunt regulator A4IC1,
provides a stable reference source referenced to C1 (–) (minus).

will overcome the

S

The overvoltage protection circuit contains output sensing voltage differential amplifier IC2 and
voltage comparator IC3A. This circuit compares the output sensing voltage with the adjustable
voltage limit level provided by potentiometer A1R415. Once triggered, the comparator’s output
is integrated (A4CR14, A4C6, and A4C9), providing an adjustable delay through R(C)403 and
A4IC3B. Both adjustments described above are accessible through the slot in the top cover.

In the event of an overvoltage, resulting either from external causes or from internal power sup­ply failure, the circuit become active. A4CR402 will be turned on, producing an output pulse.

As the first S.C.R. (CR402) is conducting, it performs two functions: It shorts out the DC supply
for the voltage protection circuit, thereby creating an overcurrent in one of the circuit breaker
coils. Simultaneously, CR402 generates a firing pulse for the main S.C.R. (CR203), which
through its ”crowbar” action short-circuits the power supply output. The a-c circuit breaker
(CB101) trips due to the action of the first S.C.R. (CR402), disconnecting the power supply from
the power line. The protection circuit is automatically re-activated with the ”turn-on” of the power
supply via CB101.

5.2.7 AUXILIARY SUPPLIES

AMPLIFIER POWER SUPPLY. This full wave, bridge rectified source is derived from a second-

ary winding on the auxiliary transformer (T202). Rectified by A1CR14, the supply is capacitor fil­tered by A1C19. A voltage regulator stage, A1IC9, followed by a string of zener diodes, A1CR16

5-4 JQE SPECIAL SVC 092611

to A1CR18, provides the operating voltage for the amplifiers (±15V) and +6.2V reference volt­age.

PRE-DRIVER POWER SUPPLY. A full-wave-rectified (A1CR10) and capacitor-filtered (A1C10)
supply is derived from a secondary winding on T202. It delivers supply voltage to the pre-driver
stage A1Q2.

CONSTANT CURRENT RETURN SUPPLY. This full-wave rectified auxiliary supply is derived
from the winding of the auxiliary power transformer. Rectified by A1CR5 and filtered by A1C5,
constant current is applied to the base of the pass transistors (via the constant current generator
stage A1Q1, thus insuring the control of the Pass-Element for zero output voltage.

5.2.8 METERING CIRCUIT

Both output voltage and output current are monitored by dual range front panel meters (M101,
M102). While the output voltage is measured directly across error sensing terminals 1 (–SENSE)
and 5 (+SENSE) of terminal block TB501, the output current is measured indirectly as a voltage
drop across the current sensing resistor (R203).

5.2.9 MONITORING CIRCUIT

Both output voltage and output current can be remotely monitored through isolated analog sig­nals available at the MONITOR PORT connector on the rear panel. The 0 to +10V monitor sig­nals correspond to 0 to +25V for output voltage and 0 to +20A for output current. A1IC5 and
A1IC7 are the isolating amplifiers for the voltage monitoring circuit. A1IC6 and A1IC8 are 2-pole
low-pass filters for the voltage and current monitor signals.

The Voltage Monitor ZERO and FS (full scale) values can be calibrated using potentiometers
A1R45 and A1R39, respectively, accessible through a slot in the top cover. Similarly, potentiom­eters A1R53 and A1R47 can be used for current monitor calibration. The voltage and current
monitor signal returns are tied together by default, but they can configured to be independent
(isolated) by removing the jumper at test point A1TP1.

JQE SPECIAL SVC 092611 5-5/(5-6 Blank)

SECTION 6 - MAINTENANCE

6.1 GENERAL

This section covers maintenance procedures, installation of optional components, calibration
and test measurements of the JQE Special Power Supplies. Conservative rating of components
and the non-congested layout should keep maintenance problems to a minimum. If trouble does
develop however, the easily removed wrap-around cover and the plug-in feature of the circuit
boards provide exceptional accessibility to all components of the supply.

6.2 DISASSEMBLY/REASSEMBLY (REFER TO FIGURE 6-1.)

WARNING

Turn power off and disconnect unit from

power source before disassembling.

6.2.1 COVER REMOVAL

The wrap-around cover may be taken off by loosening and removing its twelve (12) holding
screws, five (5) on each side and two (2) on the front panel.

6.2.2 A1 CIRCUIT BOARD REMOVAL

The A1 printed circuit board is mounted with two (2) screws and two (2) washers as shown in
Figure 6-1, which are removed from the side. Set aside hardware for reassembly. After removal
of the four printed circuit board edge connectors and 4-wire cable from A1J1, the board may be
lifted from its slide-guide.

REASSEMBLY NOTES: A1 circuit board is floating; be sure to reassemble the hardware as
shown in Figure 6-1.

JQE SPECIAL SVC 092611 6-1

FIGURE 6-1. A1 PC BOARD, REASSEMBLY

6.2.3 A5 TERMINAL BLOCK BOARD AND CR203 AND CR204 ACCESS

Separate rear panel from the chassis by removing three screws at the bottom of the rear panel.
Now the rear panel can be tilted for access to the A5 board as well as to the rear panel compo­nents CR203 and CR204.

6.2.4 A3 HEAT SINK REMOVAL

The heat sink assembly is isolated from the chassis by four (4) plastic grommets, and is
mounted with four (4) screws to the chassis bottom. After the screws are taken out, the heat
sink may be removed after disconnecting the PC board edge connector(s) and the wires from
the Quick-disconnect terminals of the thermal switch.

6.2.5 A4 OVERVOLTAGE PROTECTION CIRCUIT BOARD REMOVAL

Remove the two holding screws as indicated (Refer to Figure 6-1). Separate the edge connector
at the bottom and lift the circuit board and bracket assembly out of the chassis. The circuit board
can be separated from the bracket by removing two nuts and washers.

6.2.6 REASSEMBLY.

Reassembly of all components takes place in reverse order of the above described procedures.

6.3 TROUBLESHOOTING

Modern, high performance power supplies require thorough understanding of the problems
involved in repairing complex, solid state circuitry. Servicing beyond simple parts replacements
should consequently be attempted only by personnel thoroughly familiar with solid state compo­nent techniques and with experience in closed loop circuitry.

WARNING

The heat sink and main rectifier are electrically isolated from the chassis.

The metal parts of these components are at high d-c voltage levels

referenced to chassis

Troubleshooting charts, showing resistance and voltage readings, are of very limited usefulness
with feedback amplifiers and are not included here. Instead a detailed circuit description (Sec­tion 5), parts location diagrams, simplified functional schematics and a main schematic and
detailed schematic diagrams are presented.

The following basic steps in a case of power supply malfunctioning may also be found useful:

1. If power supply does not function at all. Check all power connections and make certain,
power supply is connected to the correct line voltage (it is normally delivered for 115V AC
operation). Verify that the input voltage is present at the a-c outlet where the unit is plugged
in.

2. No D-C Output:

• Check rear terminal block jumper (link) connections at TB501 for correct placement and
tight seat (Refer to FIG. 5-1).

• Check auxiliary supply voltages for A1 and A4 boards for 115V a-c input (see Table 6-1)

6-2 JQE SPECIAL SVC 092611

TABLE 6-1. AUXILIARY SUPPLY VOLTAGES

MEASUREMENT

POINT

A1C19 (+) +39V ±1.8V Referenced to a1C19 (–)

A1TP4 +15V ±0.5V Referenced to A1TP2

A1TP5 –15V ±0.75V Referenced to A1TP2

A1TP3 +6.2V ±0.3V Referenced to A1TP2

A1C10 (+) +12.4V ±0.5V Referenced to A1C10 (–)

A1CR7 cathode +6.5V ±0.3V Referenced to A1CR7 anode

A1C5 (–) –14.3V ±0.6V Referenced to A1C5 (+)

A1R11 (common

with A1Q1 emitter)

A4C1 (+) +29.0V ±1.5V Referenced to –OUTPUT Terminal

A4CR3 cathode +15.0V ±0.8V Referenced to –OUTPUT Terminal

A4R3 (common

with A4R2)

JQE 25-20MVPY-

27274

–9.0V ±0.6V Referenced to –OUTPUT Terminal

+6.5V ±0.3V Referenced to –OUTPUT Terminal

NOTES

1. High D-C Output: If the output voltage is high and not controllable by the voltage control,
identical steps as outlined in step 2 above for No d-c output are advisable. In addition, if the
condition persists, check the following:

• Check the pre-driver transistor (A1Q1) and the main driver (Q310) as well as all pass­element transistors located on heat sink assembly A3.

• Check the voltage control resistor (R102) for continuity. Monitor output with an oscillo­scope and observe ripple wave-form and amplitude. If high frequency oscillations are
observed, consult factory. High line-related ripple is often due to failure in one of the rec­tifier circuits.

2. Input Circuit Breaker Trips at Power-up

• Set the OVP ADJ potentiometer 1/4 turn clockwise.

• Verify that link between terminals 5 and 6 of TB501 on the rear panel is installed.

• For remote operation, verify that link between terminals 5 and 6 of TB501 on the rear
panel is removed. Verify remote programming resistor is connected between terminals 4
and 6 of TB501 on the rear panel.

3. Input Circuit Breaker Trips During Operation

• Use properly rated (output current) twisted pair wires for power terminal (+OUTPUT,
–OUTPUT) connections as well as remote error sensing

• If remote error sensing is used, use properly rated (#22AWG recommended) twisted pair
wires for sense terminal connections to the load: TB501 terminal 2 (+SENSE) and termi­nal 4 (–SENSE).

JQE SPECIAL SVC 092611 6-3

• If the unit is operated at full power with maximum input voltage, check that the ambient
operating temperature surrounding the unit is within specified limits (see PAR 1.5).

• Verify that the pass-element transistors are tight to the heat sink and that silicone grease
was used between the transistor and heat sink. If problem recurs, replace thermoswitch
mounted on heat sink assembly.

4. If the power supply is basically functioning, but poor performance is evident, inspect the test
set-up to make certain the source of the trouble is not external.

5. Poor regulation in any of the regulating modes is usually traceable to incorrectly connected
loads or faulty measurement techniques. Perform measurements as described in Paragraph

6.4.2.

6. Oscillation of the output voltage or output current is often due to a load with a large inductive
component. Twisted load wires of sufficient diameter and held as short as practical, are often
the solution to the problem.

7. Kepco Application Engineers are available for consultation or direct help in difficult service or
application problems.

6.4 POWER SUPPLY MEASUREMENTS

Measurement of the significant parameters of a power supply is a requirement for incoming
inspection, periodic maintenance, or after component replacement. Since the measurements
require special techniques to ensure correct results, suggestions for their performance are given
below.

6.4.1 REQUIRED TEST EQUIPMENT.

1. Constant AC supply voltage with provisions for “stepping” the voltage over a specified
region (105-125V); a variable autotransformer is generally adequate, if it is rated to
deliver the input current of the unit under test.

2. Resistive load, variable, with ON/OFF and SHORTING SWITCH and capable of dissi­pating the full output power of the unit under test.

3. DC voltage monitor, digital voltmeter, or power supply analyzer.

4. Precision Current sensing resistor, for current regulation measurements, four-terminal
device.

5. AC ripple monitor, sensitivity better than 1 mV. Ballantine Model 302C. or Hewlett Pack­ard Model 400H.

6. Optional: Oscilloscope, vertical sensitivity better than 0.1 mV/cm.

6-4 JQE SPECIAL SVC 092611

6.4.2 MEASUREMENT INSTRUCTIONS

a. Output Voltage Measurement. The principle governing this method of measurement is sim-

ple: DO NOT MEASURE ANY VOLTAGE DROPS DUE TO LOAD CURRENT FLOW. This
can only be avoided by measuring regulation directly at the sensing leads.

b. Source and Load Effect in Voltage Mode is defined as the amount of output voltage change

resulting from a specified change of line voltage or from a change in load resistance. It can
be expressed as an absolute change ∆E

voltage E

:

O

% Voltage Effect

c. Current Source and Mode Effect in Current Mode is defined as the amount of output current

change resulting from a specified change in line voltage or from a change in load resistance.
I t can be expressed as an absolute change ∆I

output current I

:

O

% Current Effect

d. RMS ripple may be monitored on a true RMS-reading instrument connected in parallel with

the regulation analyzer leads. Careful wire dressing and shielding, as well as good a-c
grounding are of the utmost importance if valid measurements are expected. An oscilloscope
may also be used for p-p readings of noise and ripple. An approximate RMS reading can be
calculated from the p-p reading of the oscilloscope if the reading is divided by three.

or as a percentage in reference to the total output

O

∆ E

O

-----------­E

∆ I

----------­I

O

100 %×=

O

, or as a percentage in reference to the total

O

O

100 %×=

JQE SPECIAL SVC 092611 6-5/(6-6 Blank)

SECTION 7 - ELECTRICAL PARTS LIST AND DIAGRAMS

7.1 GENERAL

This section contains the schematic diagrams, the parts location diagrams, and a list of all
replaceable electrical parts. All components are listed in alpha-numerical order of their refer­ence designations. Consult your Kepco Representative for replacement of parts not listed here.

7.2 ORDERING INFORMATION

To order a replacement part or inquire about parts not listed in the parts list, address order or
inquiry either to your authorized Kepco Sales Representative or to:

Specify the following information for each part:

• Power Supply Model number, Serial number, and Revision number stamped on the
nameplate of the unit.

• Kepco part number. See Parts List.

• Circuit Reference Designation. See Schematic Diagram.

KEPCO, INC.
131-38 Sanford Avenue
Flushing, NY 11355

• Description. See Parts List.

To order a part not listed in the parts list, give a complete description and include its function
and location.

NOTE: Kepco does not stock or sell complete power supply subassemblies as described here

and elsewhere in the instruction manual. Some of the reasons are listed below:

1. Replacement of a complete subassembly is a comparatively rare necessity.

2. Kepco's subassemblies are readily serviceable, since most of them are the "plug- in"
type.

3. The nature of a closed loop power supply system requires that subassembly replace­ment be followed by careful measurement of the total power supply performance. In
addition, depending on the function of the subassembly, extensive alignment may be
required to restore power supply performance to specified values.

If repairs involving subassembly replacements are required, please contact your local Kepco
representative or the Kepco Sales Engineering department in Flushing, New York, NY.

JQE SPECIAL SVC 092611 7-1

7.3 ABBREVIATIONS USED IN KEPCO PARTS LISTS

7.3.1 REFERENCE DESIGNATORS

A=Assembly

B = Blower (Fan)

C = Capacitor

CB = Circuit Breaker

CR = Diode

DS = Device. Signaling (Lamp)

F=Fuse

7.3.2 DESCRIPTIVE ABBREVIATIONS

A=Ampere

a-c = Alternating Current

AMP = Amplifier

AX = Axial

CAP = Capacitor

CER = Ceramic

CT = Center-tap

ºC = Degree Centigrade

d-c = Direct Current

DPDT = Double Pole, Double

Throw

DPST = Double Pole, Single

Throw

ELECT= Electrolytic

F=Farad

FILM = Polyester Film

FLAM = Flammable

FP = Flame-Proof

ºF = Degree Fahrenheit

FX = Fuse Holder

IC = Integrated Circuit

J = Jack

K = Relay

L = Inductor

LC = Light-Coupled Device

LED = Light Emitting Diode

FXD = Fixed

Ge = Germanium

H=Henry

Hz = Hertz

IC = Integrated Circuit

K = Kilo (10

m = Milli (10

3

)

-3

)

MFR = Manufacturer

MET = Metal

n=Nano (10

-9

)

NC = Normally Closed

NO = Normally Open

p = Pico (10

-12

)

PC = Printed Circuit

POT = Potentiometer

PIV = Peak Inverse Voltage

p-p = Peak to Peak

ppm = Parts Per Million

M=Meter

P=Plug

Q = Transistor

R=Resistor

T = Transformer

TB = Terminal Block

X = Socket

PWR = Power

RAD = Radial

RECT = Rectifier

RECY= Recovery

REG = Regulated

RES = Resistor

RMS = Root Mean Square

Si = Silicon

S-end = Single Ended

SPDT = Single Pole, Double

Throw

SPST = Single Pole, Single

Throw

Stud Mt.=Stud Mounted

TAN = Tantalum

TSTR = Transistor

µ = Micro (µ) (10

-6

)

V=Volt

W=Watt

WW = Wire Wound

7-2 JQE SPECIAL SVC 092611

KEPCO REPLACEMENT PARTS LIST

JQE 15-12MVPY-27274 POWER SUPPLY (Figure 7-1) CODE: 1305217

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

KEPCO

PART N O.

REC. SPARE

PART Q TY.

FIGURE 7-1. JQE 25-20MVPY-27274 POWER SUPPLY, COMPONENT LOCATIONS

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLEY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

JQE 27274 SVC 092611 7-3

KEPCO REPLACEMENT PARTS LIST

JQE 15-12MVPY-27274 POWER SUPPLY (Figure 7-1) CODE: 1305217

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

B101 1 FAN, 3-POLE MOTOR 115VAC, 50/

60HZ

@B101 1 BLADE, FAN

4.25 DIA .5 7/32 HUB

CB101 1 CIRCUIT BREAKER, MAGNETIC,

MULTIPLE COIL, 2POLE 250VAC

CR201, CR202 2 RECT., SI, STUD MT.

100V,40A

CR203 1 RECT., THYRISTOR (SCR),

100V, 40A

CR204 1 RECT., SI RECTIFIER,

300V, 15A

C1, C2 2 CAP., CERAMIC

2.2UF, 10%, 50V

C201, C202 2 CAP., ELECTROLYTIC, CAN-TYPE,

23200UF, +100 -10%, 50V

C204 1 CAP., ELECTROLYTIC, CAN-TYPE,

5800UF, + 75 -10%, 40V

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

FASCO ( JAKEL)
J238-087-8157

KENCO PLASTICS
149-0031

SENSATA TECHNOL
UPGH-14-1980-1

VISHAY DALE
40HF10

INTERNATIONAL RECT
40RCS10

INTERNATIONAL RECT
1N3211

KEMET
C340C225K5R5TA7317

CORNELL DUBILIER
DCM2322W050DC2A

UNITED CHEMI-CON
036D582G040AB2BD9026

KEPCO

PART N O.

REC. SPARE

PART Q TY.

148-0049 1

149-0031 1

127-0286 1

124-0355 1

124-0358 1

124-0164 1

117-1359 1

117-0766 1

117-0782 1

C206,C207 2 CAP., MYLAR, METALLIZED,

2UF, 10%,200V

C205 1 CAP., MYLAR, METALLIZED,

3UF, 20%,200V

DS1 1 DEVICE, SIGNALING, NEON W/INT

RES, RD LENS, 115VAC

M101 1 METER, DC MULTI-RANGE, SINGLE

SCALE, 0- 20A 2.0” 2%

M102 1 METER ,DC MULTI-RANGE, SINGLE

SCALE, 0- 30V, 2.0” 2%

R1, R2 2 RES., METAL FILM

100 OHMS, 1/4W, 1%

R101 1 RES., VAR., MULTITURN, POTEN-

TIOMETER, 2 KOHM , 2W, 5%

R102 1 RES., VAR., MULTITURN, POTEN-

TIOMETER, 30 KOHM , 2W, 5%

R201 1 RES., FIX., POWER, AX. LEADS,

7.5 OHM , 5W, 5%

R202 1 RES., FIX., POWER, AX. LEADS,

500 OHM , 5W, 5%

TRW
X663-F

CORNELL DUBILIER
MMP2W3-1M

CHICAGO MINIATURE
2110QAX1

JEWELL INSTRUMENTS
00-890118-028

HOYT ELECTRICAL
N4234-V0-30VDC

RCD COMPONENTS
GP55-1000-FT

BOURNS INCORPOR
3590S-1-202

BOURNS INCORPOR
3540S-1-303

VISHAY DALE
CW0057R500JB12

VISHAY DALE
CW-5-500-5%

117-0129 1

117-0354 1

152-0087 1

135-0452

135-0407

115-1846 1

115-1153 1

115-1204 1

115-0982 1

115-0503 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLEY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

7-4 JQE 27274 SVC 092611

KEPCO REPLACEMENT PARTS LIST

JQE 15-12MVPY-27274 POWER SUPPLY (Figure 7-1) CODE: 1305217

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

R203 1 RES., FIX., POWER, SHUNT (4

TERMINAL), 0.025 OHM , 50W, 1%

R204 1 RES. FIXED, POWER, RIBBON

2 OHM, 750W, 5%

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

TEPRO OF FLORIDA
TMK-50

KEPCO
115-2476

T201 1 TRANSFORMER, POWER KEPCO

100-1819

T202 1 TRANSFORMER, POWER,

AUXILIARY

KEPCO
100-2643

KEPCO

PART N O.

REC. SPARE

PART Q TY.

115-2333 1

115-2476

100-1819 1

100-2643 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLEY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

JQE 27274 SVC 092611 7-5

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A1 (Figure 7-2) CODE: 2351485

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

KEPCO

PART N O.

REC. SPARE

PART Q TY.

FIGURE 7-2. JQE 25-20MVPY-27274 A1 ASSEMBLY, COMPONENT LOCATIONS

CR1, CR2, CR4,
CR8

CR3, CR6, CR9,
CR13

CR5, CR10, CR14 3 RECT., ENCAPSULATED BRIDGE

CR7 1 DIODE, ZENER,

CR11, CR12 2 RECT., SI,

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

4 RECT., SI, AX. LEADS,

3000V, 200MA

4 RECT., SWITCHING DIODE,

75V, 0.4A

200V, 1A

6.5V, 5%

100V, 1.5A

RECTRON, USA
R3000-F

AMERICAN POWER
1N4148-AMMO

FAIRCHILD SEMICOND
W02G

AMERICAN POWER
1N763-1

DIOTEC ELECTRONICS
1N5392

124-0178 1

124-0437 1

124-0346 1

121-0028 1

124-0133 1

7-6 JQE 27274 SVC 09-2611

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A1 (Figure 7-2) CODE: 2351485

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

CR15 1 DIODE, REFERENCE,

6.2V, 5%

CR16, CR17, CR18 3 DIODE, ZENER,

5.1V, 5%

CR19, CR20 2 RECT., SCHOTTKY, AX. LDS.,

40V,1A

C1 1 CAP., MYLAR, METALLIZED,

0.1UF, 20%, 600V

C2, C3 2 CAP., ELECTROLYTIC, AX. LEADS,

220UF, 20%, 16V

C4 1 CAP., MYLAR, METALLIZED,

0.1UF, 5%, 250V

C5 1 CAP., ELECTROLYTIC, AX. LEADS,

220UF, 20%, 25V

C6, 8, 12-15, 17,
20, 22, 27, 32

11 CAP., CERAMIC,

0.1UF, 10%, 50V

C7 1 CAP., MYLAR, METALLIZED,

1UF, 10%, 200V

C9, C18 4 CAP., CERAMIC,

0.01UF, 10%, 50V

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

AMERICAN POWER
1N827

CENTRAL SEMICOND
1N5338B LEAD FREE

ON SEMICONDUCTOR
1N5819RLG

AMERICAN SHIZUK
X663F 0.1 20% 600VDC

CORNELL DUBILIER
MALLORY #SKA221M016AT

VISHAY ROEDERST
MKT1813-410-254-G

ILLINOIS CAPACITOR
227TTA025M

VISHAY AMERICAS
A104K15X7RF5UAA

CORNELL DUBILIER
MMP2W1K-F

VISHAY BC COMPONENTS
A103K15X7RF5UAA

KEPCO

PART N O.

REC. SPARE

PART Q TY.

121-0062 1

121-0093 1

121-0578 1

117-0316 1

117-0512 1

117-0363 1

117-0713 1

117-1052 1

117-0395 1

117-1053 1

C10 1 CAP., ELECTROLYTIC, AX. LEADS,

220UF, 20%, 16V

C11 1 CAP., CERAMIC,

0.047UF, 10%, 50V

C16 1 CAP., TANTALUM,

6.8UF, 20%, 35V

C19 1 CAP., ELECTROLYTIC, AX. LEADS,

470UF, 20%, 50V

C21 1 CAP., CERAMIC,

1UF, 10%, 50V

C23, C26, C28,
C31

4 CAP., CERAMIC,

1UF, 10%, 100V

C24, C29 2 CAP., CERAMIC,

0.033UF, 10%, 50V

C25, C30 2 CAP., CERAMIC,

0.015UF, 10%, 50V

IC1, IC2, IC6, IC8 4 I.C. LOW NOISE, HIGH-SPEED,

PRECISION, OP AMP

IC3 1 I.C. PRECISION INSTRUMENTATION

AMPLIFIER

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

KEPCO
117-0677

BC COMPONENTS
A473K17X7RFVVWJ

VISHAY SPRAGUE
173D685X0035XE3

ILLINOIS CAPACITOR
477TTA050M

VISHAY CERA-MIT
K105K20X7RF5UH5

BC COMPONENTS
K105K40X7RHTTXD

BC COMPONENTS
A333K15X7RFVVWG

BC COMPONENTS
A153K15X7RFVVWC

LINEAR TECH
LT1007CN8

BURR-BROWN
INA118P

117-0677 1

117-1054 1

117-0968 1

117-0619 1

117-0999 1

117-1087 1

117-1191 1

117-1190 1

250-0152 1

250-0332 1

JQE 27274 SVC 09-2611 7-7

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A1 (Figure 7-2) CODE: 2351485

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

IC4 1 I.C. DUAL PRECISION OP.AMP LINEAR TECH.

LT1013CN8

IC5, IC7 2 I.C., ISOLATION AMPLIFIER, 3-

PORT

IC9 1 I.C., 3-TERMINAL POSTIVE VOLT-

AGE REGULATOR ,

J1 1 JACK, SOCKET, CABLE CONNEC-

TOR, 4PINS, HEADER, PC MT

ANALOG DEVICES
AD210JN

SIG
UA78M15UC

JST CORP.
B4B-XH-A

Q1 1 TRANSISTOR, SI, NPN, POWER CENTRAL SEMICOND

2N3054

Q2 1 TRANSISTOR, SI, NPN, SMALL SIG-

NAL

Q3, Q4 2 TRANSISTOR, SI, NPN, SMALL SIG-

NAL

R1, R18 2 RES., FIX., CARBON FILM,

10 OHM , 1/4W, 5%

R2 1 RES., FIX., CARBON FILM,

2.7 KOHM , 1W, 5%

R3 1 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 10 KOHM ,

RAYTHEON MFG
1190094

CENTRAL SEMICOND
2N5449

IRC, INC.
CF 1/4-100-J T&R

YAGEO
CRF-100 JTJ-52 2K7

BOURNS INCORP
3009P-1-103

3/4W, 10%

R4, R8 1 THERMISTOR, PTC, 9.4OHM

@25DEGC

KEYSTONE THERMOM
YPBL9.40T

KEPCO

PART N O.

REC. SPARE

PART Q TY.

250-0198 1

250-0785 1

250-0064 1

143-0810 1

119-0060 1

119-0094 1

119-0093 1

115-2230 1

115-0978 1

115-2481 1

115-3116 1

R5 1 RES., FIX., CARBON FILM,

3 KOHM , 1/4W, 5%

R6, R17 2 RES., FIX., CARBON FILM,

560 OHM , 1/2W, 5%

R7 1 RES., FIX., CARBON FILM,

12 KOHM , 1/4W, 5%

R9. R13 2 RES., FIX., PRECISION, METAL-

FILM, 511 OHM , 1/4W, 1%

R10 1 RES., FIX., PRECISION, METAL

FILM, 301 OHM , 1/8W, 1%

R11 1 RES., FIX., CARBON FILM,

IRC, INC.
CF-1/4 302 J T&R

IRC, INC.
CF-1/2 561 J T&R

IRC, INC.
CF-1/4 123 J T&R

VISHAY DALE
CMF55511R00FKEA

IRC
CEA TYPE RN55D3010F

115-2294 1

115-0888 1

115-2276 1

115-2092 1

115-2261 1

115-1859 1

130 OHM , 1/2W, 5%

R12, R43, R51 3 RES., FIX., PRECISION, METAL

FILM, 210 OHM , 1/8W, 1%

R14 1 RES., FIX., CARBON FILM,

27 OHM , 1/4W, 5%

R15 1 RES., FIX., PRECISION, METAL

FILM, 6.65 KOHM , 1/4W, 1%

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

VISHAY DALE
CCF55210RFKE36

IRC, INC.
CF-1/4 270 J

VISHAY DALE
CCF-55 6651 F R36

115-2177 1

115-2317 1

115-2820 1

7-8 JQE 27274 SVC 09-2611

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A1 (Figure 7-2) CODE: 2351485

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

R16 1 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 1 KOHM ,
3/4W, 10%

R19, R29, R48,
R54, R55

5 RES., FIX., PRECISION, METAL

FILM, 10 KOHM , 1/8W, 1%

R20A, R20B 2 RESISTOR, MATCHED SET

10K/10K

R21 1 RES., FIX., PRECISION, METAL

FILM, 5.62 KOHM , 1/8W, 1%

R22 1 RES., FIX., PRECISION, METAL

FILM, 100 OHM , 1/8W, 1%

R23 1 RES., FIX., PRECISION, METAL-

FILM, 1.1 KOHM , 1/4W, 1%

R25 1 RES., FIX., POWER, AX. LEADS,

1.5 KOHM , 3W, 5%

R26 1 RES., FIX., METAL FILM,

20 KOHM , 1/8W, 0.1%

R27 1 RES., FIX., PRECISION, METAL

FILM, 232 OHM , 1/8W, 1%

R28 1 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 500 OHM ,
3/4W, 10%

R30 1 RES., FIX., PRECISION, METAL

FILM, 1 KOHM , 1/4W, 1%

R31 1 RES., FIX., PRECISION, METAL

FILM, 3.92 KOHM , 1/8W, 1%

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

BOURNS
3009P-FV7-202LF

VISHAY DALE
CCF5510K0FKE36

VISHAY DALE
PER KEPCO DWG (PTF-56)

VISHAY DALE
CCF555K62FKE36

VISHAY DALE
CCF-55 1000 F R36

IRC
CES RN60D1101F

VISHAY DALE
CW02B1K500JE70

VISHAY DALE
PTF5620K000BYEB

VISHAY DALE
RN55D2320F

BOURNS INCORP
3009P-1-501

VISHAY DALE
CCF-55-1001-F-R36

VISHAY DALE
CCF553K92FKR36

KEPCO

PART N O.

REC. SPARE

PART Q TY.

115-2405 1

115-2174 1

234-0006 1

115-2409 1

115-2598 1

115-1860 1

115-1189 1

115-2884 1

115-2310 1

115-2398 1

115-2180 1

115-2179 1

R32 1 RES., FIX., PRECISION, METAL

FILM, 499 KOHM , 1/8W, 1%

R34 1 RES., FIX., CARBON FILM,

10 KOHM , 1/4W, 5%

R35 1 RES., FIX., METAL FILM,

100 KOHM , 1/8W, 0.1%

R37 1 RES., FIX., PRECISION, METAL

FILM, 1 KOHM , 0.12W, 0.1%

R38, R46 2 RES., FIX., PRECISION, METAL-

FILM, 19.1 KOHM , 1/4W, 1%

R39, R47 2 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 2 KOHM ,
3/4W, 10%

R40, R44, R52 3 RES., FIX., PRECISION, METAL-

FILM, 49.9 KOHM , 1/4W, 1%

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

JQE 27274 SVC 09-2611 7-9

VISHAY DALE
CCF-55 4993 F R36

IRC, INC.
CF-1/4-103-J T&R

VISHAY DALE
CMF-55 1003 B T-9 R36

VISHAY DALE
CMF501K0000BEEB

VISHAY DALE
RN60

BOURNS INCORP
3009P-1-202

VISHAY DALE
CMF5549K900FKEB

115-2309 1

115-2211 1

115-2864 1

115-3202 1

115-1123 1

115-2405 1

115-1857 1

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A1 (Figure 7-2) CODE: 2351485

REFERENCE

DESIGNATOR

R41, R42, R49,
R50

QTY. DESCRIPTION

4 RES., FIX., PRECISION, METAL

FILM, 3.74 KOHM , 1/8W, 1%

R45, R53 2 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 100 KOHM
, 3/4W, 10%

TP1, TP2, TP3,

5 TEST POINT, 0.1” LEAD SPACING COMPONENTS CORP

TP4, TP5

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

VISHAY DALE
CCF553K74FKE36

BOURNS INCORP
3009P-1-104

ATP-402-10

KEPCO

PART N O.

REC. SPARE

PART Q TY.

115-2512 1

115-2399 1

173-0029 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

7-10 JQE 27274 SVC 09-2611

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A3 (Figure 7-3) CODE: 1130049

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

KEPCO

PART N O.

REC. SPARE

PART Q TY.

FIGURE 7-3. JQE 25-20MVPY-27274 A3 ASSEMBLY, COMPONENT LOCATIONS

Q301-304, Q306­309

Q305, Q310 2 TRANSISTOR, SI, NPN, POWER CENTRAL SEMICOND

8 TRANSISTOR, SI, NPN, POWER KEPCO

119-0075

119-0075 1

119-0060 1

2N3054

S301 1 SWITCH, THERMOSTAT (N.O.),

SP ST W/QC

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

HONEYWELL/ELMWOOD
2450G-8081-0084

127-0248 1

JQE 26954 SVC 09-2611 7-11

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A3A1 (Figure 7-4) CODE: 2360179

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

KEPCO

PART N O.

FIGURE 7-4. JQE 25-20MVPY-27274 A3A1 ASSEMBLY, COMPONENT LOCATIONS

REC. SPARE

PART Q TY.

C301 1 CAP., MYLAR, METALLIZED,

0.1UF, 5%, 250V

CR301 1 RECT., SI,

100V, 1.5A

R301-304 4 RES., FIX., POWER, AX. LEADS,

0.1 OHM , 3W, 5%

R305 1 RES., FIX., CARBON FILM,

100 OHM , 1/4W, 5%

R306 1 RES., FIX., CARBON FILM,

1 KOHM , 1/4W, 5%

R315 1 RES., FIX., CARBON FILM,

10 OHM , 1/4W, 5%

VISHAY ROEDERST
MKT1813-410-254-G

DIOTEC ELECTRONICS
1N5392

VISHAY DALE
LVR03R1000JE70

IRC, INC.
CF 1/4 101 J T&R

IRC, INC.
CF-1/4 102 J T&R

IRC, INC.
CF 1/4-100-J T&R

117-0363 1

124-0133 1

115-0819 1

115-2231 1

115-2238 1

115-2230 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

7-12 SVC09-2611

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A3A2 (Figure 7-5) CODE: 2360180

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

KEPCO

PART N O.

FIGURE 7-5. JQE 25-20MVPY-27274 A3A2 ASSEMBLY, COMPONENT LOCATIONS

REC. SPARE

PART Q TY.

R307-310 4 RES., FIX., POWER, AX. LEADS,

0.1 OHM , 3W, 5%

R311 1 RES., FIX., CARBON FILM,

100 OHM , 1/4W, 5%

R312 1 RES., FIX., CARBON FILM,

22 OHM , 1/4W, 5%

R313 1 RES., FIX., CARBON FILM,

1 KOHM , 1/4W, 5%

R314 1 RES., FIX., POWER, AX. LEADS,

750 OHM , 5W, 5%

VISHAY DALE
LVR03R1000JE70

IRC, INC.
CF 1/4 101 J T&R

IRC, INC.
CF-1/4 220J T&R

IRC, INC.
CF-1/4 102 J T&R

VISHAY DALE
CW-5

115-0819 1

115-2231 1

115-2494 1

115-2238 1

115-1980 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

SVC09-2611 7-13

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A4 (Figure 7-6) CODE: 2362920

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

DETAIL "A"

KEPCO

PART N O.

REC. SPARE

PART Q TY.

FIGURE 7-6. JQE 25-20MVPY-27274 A4 ASSEMBLY, COMPONENT LOCATIONS

CR1 1 RECT., ENCAPSULATED BRIDGE

200V, 1A

CR3 1 DIODE, ZENER,

15V, 5%

CR4, CR6 2 DIODE, ZENER,

4.7V, 5%

CR5 1 RECT., SWITCHING DIODE,

75V, 0.4A

CR12, CR13 2 RECT., SI, SCHOTTKY, AX. LDS.

40V, 1A

CR14 1 DIODE, CURRENT REGULATOR CENTRAL SEMICOND

FAIRCHILD SEMICOND
W02G

AMERICAN POWER
1N4744A AMMO PACK

PHILIPS SEMICOND
1N4732A *

AMERICAN POWER
1N4148-AMMO

ON SEMICONDUCTOR
1N5819RLG

124-0346 1

121-0057 1

121-0091 1

124-0437 1

124-0578 1

121-0083 1

CCL0750

CR402 1 RECT., THYRISTOR (SCR),

200V, 8A

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

CENTRAL SEMICOND
CS220-8B

124-0350 1

7-14 SVC09-2611

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A4 (Figure 7-6) CODE: 2362920

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

C1 1 CAP., ELECTROLYTIC, AX. LEADS,

140UF, +100 -10%, 40V

C2, C4, C5, C7, C8 5 CAP., CERAMIC,

0.1UF, 10%, 50V

C3 1 CAP., CERAMIC,

0.047UF, 10%, 50V

C6, C9 2 CAP., CERAMIC,

0.01UF, 10%, 50V

C12 1 CAP., TANTALUM,

4.7UF, 10%, 15V

C13 1 CAP., CERAMIC,

1000PF, 10%, 200V

C14 1 CAP., CERAMIC,

1UF, 10%, 50V

IC1 1 I.C. ADJ. REFERENCE (2.5-37V)

600UA-100MA

IC2 1 I.C. PRECISION SINGLE SUPPLY

OP.AMP

IC3 1 I.C. DUAL VOLTAGE COMPARATOR

OP.AMP.

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

SANGAMO COMPONENTS
052FE141Q040B

VISHAY AMERICAS
A104K15X7RF5UAA

BC COMPONENTS
A473K17X7RFVVWJ

VISHAY BC
A103K15X7RF5UAA

VISHAY SPRAGUE
173D475X9015V

VISHAY BC
A102K15X7RK5-UAA

VISHAY CERA-MIT
K105K20X7RF5UH5

MOT.
TL431AILP

PMI
OP-90GP

NAT.
LM393AN

KEPCO

PART N O.

REC. SPARE

PART Q TY.

117-0706 1

117-1052 1

117-1054 1

117-1053 1

117-1112 1

117-1084 1

117-0999 1

250-0239 1

250-0216 1

250-0228 1

Q1 1 TRANSISTOR, SI, NPN, SMALL SIG-

NAL

RC403, R415 2 RES., VAR., MULTITURN, TRIM-

MER, COMP. OR CERM., 10 KOHM ,

RAYTHEON MFG
1190094

BOURNS INCORP
3009P-1-103

119-0094 1

115-2481 1

3/4W, 10%

RN2A, RN2B 2 RES, NET.

40K/10K

R1 1 RES., FIX., CARBON FILM,

330 OHM , 2W, 5%

R2 1 RES., FIX., CARBON FILM,

510 OHM , 1/2W, 5%

R3 1 RES., FIX., PRECISION, METAL-

FILM, 4.02 KOHM , 1/4W, 1%

R4 1 RES., FIX., POWER, AX. LEADS,

0.5 OHM , 3W, 3%

R5, R8 2 RES., FIX., CARBON FILM,

1 KOHM , 1/4W, 5%

R6 1 RES., FIX., PRECISION,

2.49 KOHM , 1/8W, 0.1%

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.

PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS AT
LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

PRECISION RESIS
PRP#-8463

RCD COMPONENTS
CF200S 3300 J TB

KOA/SPEER
CF1/2 511 J T52A

VISHAY DALE
CCF554K02FKE36

VISHAY DALE
CW02BR5000HE70

IRC, INC.
CF-1/4 102 J T&R

VISHAY DALE
PTF-56 2K490 B T-13 R36

234-0018 1

115-0882 1

115-0824 1

115-3021 1

115-1880 1

115-2238 1

115-2970 1

SVC09-2611 7-15

KEPCO REPLACEMENT PARTS LIST

JQE 25-20MVPY-27274 ASSEMBLY A4 (Figure 7-6) CODE: 2362920

REFERENCE

DESIGNATOR

QTY. DESCRIPTION

R7 1 RES., FIX., CARBON FILM,

10 OHM , 1/4W, 5%

R9 1 RES., FIX., PRECISION, METAL

FILM, 49.9 KOHM , 1/8W, 1%

R10 1 RES., FIX., PRECISION, METAL-

FILM, 7.5 KOHM , 1/4W, 1%

R11 1 RES., FIX., PRECISION, METAL

FILM, 4.99 KOHM , 1/8W, 1%

R12, R13, R22 3 RES., FIX., PRECISION, METAL

FILM, 1 KOHM , 1/4W, 1%

R15 1 RES., FIX., PRECISION, METAL

FILM, 15 KOHM , 1/8W, 1%

R16 1 RES., FIX., CARBON FILM,

100 OHM , 1/4W, 5%

R19 1 RES., FIX., PRECISION, METAL-

FILM, 150 OHM , 1/4W, 1%

R20 1 RES., FIX., PRECISION, METAL

FILM, 2 KOHM , 1/8W, 1%

R33 1 RES., FIX., CARBON FILM,

2.2 KOHM , 1/4W, 5%

MFRS. NAME & PART NO.

(SEE BOTTOM NOTE)

IRC, INC.
CF 1/4-100-J T&R

VISHAY DALE
CMF5549K900FEEA

IRC
CES RN60D7501F

VISHAY DALE
CFF-55 4991 F R36

VISHAY DALE
CCF-55-1001-F-R36

VISHAY DALE
CCF5515K0FKE36

IRC, INC.
CF 1/4 101 J T&R

VISHAY DALE
CCF-55

VISHAY DALE
CCF-55 2001 F R36

RCD COMPONENTS
CF25-222-JT

KEPCO

PART N O.

REC. SPARE

PART Q TY.

115-2230 1

115-2755 1

115-1853 1

115-2401 1

115-2180 1

115-2452 1

115-2231 1

115-2091 1

115-2334 1

115-2382 1

R34, R35, R36,
R37

TP1, TP2, TP3,
TP4, TP5

fi

4 RES., FIX., METAL FILM,

100 KOHM , 1/8W, 0.1%

VISHAY DALE
CMF-55 1003 B T-9 R36

5 TEST POINT, 0.1” LEAD SPACING COMPONENTS CORP

ATP-402-10

115-2864 1

173-0029 1

NOTE: REPLACEMENT PARTS MAY BE ORDERED FROM KEPCO, INC. ORDERS SHOULD INCLUDE KEPCO PART NUMBER AND DESCRIPTION.
PLEASE NOTE: THE MANUFACTURER'S NAME AND PART NUMBER LISTED FOR EACH ITEM ON REPLACEMENT PARTS LISTS REPRESENTS
AT LEAST ONE SOURCE FOR THAT ITEM AND IS LISTED SOLELY FOR THE CONVENIENCE OF KEPCO EQUIPMENT OWNERS IN OBTAINING
REPLACEMENT PARTS LOCALLY. WE RESERVE THE RIGHT TO USE EQUIVALENT ITEMS FROM ALTERNATE SOURCES. KEPCO, INC.

7-16 SVC09-2611

CD R P Q

P401

1
2
3
4
5
6

A2-T201

+

A2-C201

23.2m

A2-R201

7.5/5W

J203

1
2
3
4
5
6

J207

1
2
3
4
5
6

A2-R203

0.025/50W
A2-R204
2/750W

R314
750/5W

A3A2-P302

123456789

J202

123456789

J205

1
2
3
4
5
6
7
8
9

R301-304

0.1/3W

R305 100

R306 1K

J206

1
2
3
4
5
6
7
8

9
10
11
12

A3A1-P301

12345

6

J208

12345

6

P2

1
2
3
4
5
6

A2-CR201
40HF10

P501

1
2
3
4
5
6
7
8

9
10
11
12

J201

1
2
3
4
5
6
7
8
9
10
11
12

1T

2T

3T

4T

5T

6T

7T

TB1 @T201

P3

1
2
3
4
5
6

C204/+

1

C204/-

1

FP-CB101

A1

B1

A2 B2

C2

D2

A5-

P

1

A5-

P

1

J204

1
2
3
4
5
6

A1-P3

1
2
3
4

R

P4

1
2
3
4
5
6
7
8
9
10
11
12

P5

1
2
3
4
5
6
7
8
9

Q306-309
2N3773

A2-T202

R

A

FP-M101x1(+)C(-)

C301

0.1

R307-310

0.1/3W

J1

1
2
3
4

1

2

3

4

5

A2-TB202

V

FP-M102

x1(+)C(-)

+

A2-C202

23.2m

R311

100

A2-CR202
40HF10

Q310
2N3054

A3-S301

CR301
SI-1

R315
10

FP-R102

30K

+

A2-C204

5.8m

A2-C206

A2-C207

R313 1K

A2-R202
500/5W

FP-R101

2K

Q305
2N3054

Q301-304
2N3773

R312
22

A

B

A2-TB201

A2-C205

CC_RS

+VRS

RET_RES

HS_DRV

+VDRV

VDRV_RT

+OUT_MON

-OUT_MON

CHASSIS_GND

Er

IS

CIRCUIT BREAKER
(FRONT PANEL)

A2- CHASSIS LEVEL

FP- FRONT PANEL LEVEL

MAIN POWER
TRANSFORMER

AUX.TRANSFORMER

RETURN

+SENSE_RES

CURR_CTRL_WP

CONTROL BOARD

A1

MAIN RECTIFIER

MAIN FILTER

CTRL_AC2

RS_AC1

CTRL_AC1

DRV_AC1

RS_AC2

DRV_AC2

O

CURRENT SENSING
RESISTOR

OUTPUT
CAPACITOR

FP-VOLTMETER

FP-AMMETER

12

HEAT SINK
THERMO-SWITCH

SUB-ASSY #2SUB-ASSY #1

CC_RS

RET_RES

HS_OUT

A3

PASS-ELEMENT ASSY

NULL

CURR_CTRL_CW

-SENSE_RES

Rr_2

-SENSING

Rr_1

+SENSING

CHASSIS

A

CONTROLLI

N

BOARD

CR203_K

AC1_OVP

-SENSING

CR203_G

AC2_OVP

+SENSING

A4

OVP BOARD

*

*

*

HS_DRV

VMON

CMON

CMON_RT

VMON_RT

iso. circuitVMON ZERO(R45)

CMON ZERO(R53)

VMON FS(R39)

CMON FS(R47)
Eout ZERO(R3)
Eout FS (R16)
Iout FS(R28)

CAL

OVP LEVEL(R415)
OVP DELAY(RC403)ADJ

ohms" and Capacitor values i

n

therwise specified.
or the components marked wit

h

pin 1- 2 and between pin 3- 4
he PS in local error sensing.
mote error sensing (=Kelvi

n

in 5- 6- 7 (factory default)
Voltage Control. Remove th

e

Remote Resistive Voltag

e

CW CW

BP- BACK PANEL LEVEL

+15V

-15V

+15V

-15V

+15V

-15V

+15V

-15V

+15V

-15V

+15V

+15V

+15V

-15V

-15V

+15V

+15V

-15V

CURR_CTRL_WP

CURR_CTRL_CW

-SENSE_RES

-SENSE_RES

CURR_CTRL_WP

+SENSE_RES

+6.2V

+6.2V CURR_CTRL_CW

VMON_RT

VMON

-SENSING

+SENSE_RES-C_AMPL

-SENSING

-C_AMPL

+VOSS1

-VOSS1

+SENSING

+VOSS1

-VOSS1

VMON_RT

VMON

CMON_RT
CMON

+VOSS2

-VOSS2

+VOSS2

-VOSS2

CMON_RT

CMON

+6.2V

R20A 10K

R2

2.7K

3

1
2
3
4
5
6

R12
210

R53KR6

560

R20B 10K

C18

0.01

C4

0.1

C27

0.1

C32

0.1

+

-

IC8
LT1007

3

2

6

7

1

4

8

CR9
1N4148

CR11
SI-1

+

C5
220

CR2

1240178
CR4
1240178

R9
511

R39 2K

1 3-CW

2

R10
301

C8

0.1

CR3
1N4148

+

C3

220

C11

0.047

C25
15n

C24
33n

CR8
1240178

CR7

6.5V

R31

3.92K

R35B
1K

R26 20K

R13
511

R21 5.62K

IC5
AD210

19

17

14
15

18

2

30

29

16

1

3
4

+IN

-IN

+VISS

-VISS

ICOM

OCOM

PWR

PWRCOM

FB

VO

+VOSS

-VOSS

IC7
AD210

19

17

14
15

18

2

30

29

16

1

3
4

+IN

-IN

+VISS

-VISS

ICOM

OCOM

PWR

PWRCOM

FB

VO

+VOSS

-VOSS

CR19
1N5819

C17

0.1

+

-

IC4A
LT1013

3

2

1

84

R4

9.4/ PTC

R32
499K

CR20
1N5819

IC3
INA118

3

2
1

8

6

5

74

+IN

-IN

RG1

RG2

Vo

Ref

V+V-

P2 @ J204

1
2
3
4
5
6

CR13
1N4148

R23

1.1K

C13

0.1

C15

0.1

R41

3.74K

R42

3.74K

R29
10K

R17
560

R14
27

C26

1.0

C23

1.0

R3
10K

13-CW

2

R38

19.1K

R40 49.9K

R54
10K

R55
10K

+

C16

6.8

R25

1.5K

C14

0.1

C12

0.1

C7

1.0

R50

3.74K

R19
10K

R49

3.74K
C28

1.0

C31

1.0

C30
15n

C29
33n

R16

2K

13-CW

2

R15

6.65K

R18 10

TP2

1

2

R47 2K

1 3-CW

2

TP1

1

2

R46

19.1K

R11
130

~

~

+-

CR10
200V/1A

2

1

4

3

R48 10K

TP3

1

2

~

~

+-

CR14
200V/1A

2

1

4

3

R8

9.4/ PTC

+

-

IC1
LT1007

3

2

6

7

1

4

8

TP5

1

2

TP4

1

2

Q4

2N4401

CR15

6.2V

R28 500

13-CW

2

C20

0.1

C22

0.1

CR17

5.1V/5W

CR18

5.1V/5W

IC9
LM341T-15

1 3

2

VIN VOUT

GND

+

C2
220

R43
210

R44

49.9K

Q3

2N4401

R7
12K

R52

49.9K

+

-

IC2
LT1007

3

2

6

7

1

4

8

R27
232

R30 1K

R51
210

R45
100K

1 3-CW

2

R53
100K

1 3-CW

2

C21

1.0u

R34
10K

CR12
SI-1

R22
100

+

-

IC6
LT1007

3

2

6

7

1

4

8

Q1

2N3054

+

C19
470

+

C10
220

Q2

1190094

2

13

CR6
1N4148

CR1
1240178

CR16

5.1V/5W

C9

0.01

+

-

IC4B
LT1013

5

6

7

84

R1 10

C1

0.1

R35A 99K

C6

0.1

~

~

+-

CR5
200V/1A

2

1

4

3

CC_RS

+VRS

RET_RES

HS_DRV

+VDRV

VDRV_RT

DRV_AC2

DRV_AC1

RS_AC2

RS_AC1

CTRL_AC1
CTRL_AC2 Rr_1

Rr_2

NULL

+OUT_MON

-OUT_MON

CHASSIS_GND

Er

CURRENT ERROR
AMPLIFIER

CURRENT SENSING
AMPLIFIER

CURRENT
REFERENCE

VOLTAGE ERROR
AMPLIFIER

HS DRIVER
AUX. PS

RETURN
AUX. PS

HS DRIVER

CONTROL
AUX. PSs

Ib ADJ
(for FS Voltage Adj)

VOLTAGE MODE
OFFSET ADJ

FS Current Adj

CC RETURN
PS

*

values in "ohms" and Capacitor values
rads", unless otherwise specified.
ts marked with "*" are model dependent,
always used. Consult Parts List for

RETURN

FS VMON Adj

Zero VMON
Adj

Zero CMON
Adj

FS CMON Adj

CURRENT MONITOR

VOLTAGE MONITOR

Isolated Circui

t

*

+15V

-15V

+6.2V

ISO-GND

GND

OUT POWER-SENSE
NETWORK

FIGURE 7-8. AMPLIF

I

P

©

+15V

+15V+15V +15V

+15V

+15V

+6.5V

+6.5V

GATE

+6.5V

+6.5V

LOC_RET LOC_RET

LOC_RET LOC_RET

LOC_RET

207

R1
330

+

-

IC3A
LM393

3

2

1

84

TP4

1

2

TP3

1

2

TP1

1

2

IC1

TL431

2 3

1

C13

0.001

CR5
1N4148

+

C1
140

CR402
200V/8A

3

1 2

C5

0.1

R415
10K

13-CW

2

CR3
15V

R4

0.5

TP5

1

2

R7 10CR4

4.7V

R8
1K

C9

0.01

+

-

IC3B
LM393

5

6

7

84

R(C)403
10K

13-CW

2

R20 2K

TP8

1

2

R6

2.49K

R3

4.02K

R2
510

R9 49.9K

R10

7.5K

A

B

RN2

40K(A)/10K(B)

+

-

IC2

LT1006

3

2

6

7

8

451

C4

0.1

C

4

R11

4.99K

R12
1K

R19 150

C2

0.1

+

C12

4.7

CR14
1N5297

C14

1.0

R13
1K

CR12

1N5819

CR13
1N5819

C6

0.01

R22 1K

R5
1K

R34 100K

R35
100K

R37
100K

R36 100K

TP2

1

2

C3

0.047

~

~

+-

CR1
200V/1A

2

1

4

3

AC1_OVP

+SENSING

CR203_K

CR203_G

AC2_OVP

OVP CIRCUIT

NOTE:
Resistor values in "ohms" and

C

in "microfarads", unless other

w

"OVP DELAY ADJ""OVP LEVEL ADJ"

-SENSING

©

FIGURE 7-9. OVERV

O

A4, SC

H