
Programmable DC Power Supply
ISO-9001 CERTIFIED MANUFACTURER

This manual contains proprietary information, which is protected by
copyright. All rights are reserved. No part of this manual may be
photocopied, reproduced or translated to another language without
prior written consent of Good Will company.
The information in this manual was correct at the time of printing.
However, Good Will continues to improve products and reserves the
rights to change specification, equipment, and maintenance
procedures at any time without notice.
Good Will Instrument Co., Ltd.
No. 7-1, Jhongsing Rd., Tucheng Dist., New Taipei City 236, Taiwan.

TABLE OF CONTENTS
Table of Contents
SAFETY INSTRUCTIONS .................................................. 5
GETTING STARTED .......................................................... 9
PSU Series Overview................................................ 10
Appearance .............................................................. 15
Theory of Operation ................................................ 23
OPERATION .................................................................. 34
Set Up ..................................................................... 36
Basic Operation ....................................................... 49
Parallel / Series Operation ...................................... 67
Test Scripts .............................................................. 85
CONFIGURATION .......................................................... 93
Configuration Overview ........................................... 94
ANALOG CONTROL ...................................................... 116
Analog Remote Control Overview ...........................117
Remote Monitoring.................................................135
Isolated Analog Control Option ..............................142
COMMUNICATION INTERFACE .................................... 157
Interface Configuration ...........................................158
FAQ .............................................................................. 192
APPENDIX .................................................................... 193
PSU Factory Default Settings ..................................194
Error Messages & Messages ...................................197
LED ASCII Table Character Set ................................198
PSU Specifications .................................................199
3

PSU Series User Manual
PSU Dimensions .................................................... 207
Certificate Of Compliance ...................................... 209
INDEX .......................................................................... 210
4

SAFETY INSTRUCTIONS
Warning: Identifies conditions or practices that
could result in injury or loss of life.
Caution: Identifies conditions or practices that
could result in damage to the PSU or to other
properties.
Attention Refer to the Manual
Protective Conductor Terminal
SAFETY INSTRUCTIONS
This chapter contains important safety
instructions that you must follow during
operation and storage. Read the following before
any operation to insure your safety and to keep
the instrument in the best possible condition.
Safety Symbols
These safety symbols may appear in this manual or on the
instrument.
5

PSU Series User Manual
Do not dispose electronic equipment as unsorted
municipal waste. Please use a separate collection
facility or contact the supplier from which this
instrument was purchased.
General
Guideline
CAUTION
Do not place any heavy object on the PSU.
Avoid severe impact or rough handling that
leads to damaging the PSU.
Do not discharge static electricity to the PSU.
Use only mating connectors, not bare wires, for
the terminals.
Do not block the cooling fan opening.
Do not disassemble the PSU unless you are
qualified.
(Measurement categories) EN61010-1:2010 and EN61010-2-030
specifies the measurement categories and their requirements as
follows. The PSU falls under category II.
Measurement category IV is for measurement performed at the
source of low-voltage installation.
Measurement category III is for measurement performed in the
building installation.
Measurement category II is for measurement performed on the
circuits directly connected to the low voltage installation.
0 is for measurements performed on circuits not directly
connected to Mains.
AC Input voltage range: 85Vac~265Vac
Frequency: 47Hz to 63Hz
To avoid electrical shock connect the protective
grounding conductor of the AC power cord to
an earth ground.
Safety Guidelines
6

SAFETY INSTRUCTIONS
Disconnect the power cord before cleaning.
Use a soft cloth dampened in a solution of mild
detergent and water. Do not spray any liquid.
Do not use chemicals containing harsh material
such as benzene, toluene, xylene, and acetone.
Location: Indoor, no direct sunlight, dust free,
almost non-conductive pollution (Note below)
Relative Humidity: 20%~ 85% (no condensation)
Altitude: < 2000m
Temperature: 0°C to 50°C
(Pollution Degree) EN61010-1:2010 and EN61010-2-030 specifies
the pollution degrees and their requirements as follows. The PSU
falls under degree 2.
Pollution refers to “addition of foreign matter, solid, liquid, or
gaseous (ionized gases), that may produce a reduction of dielectric
strength or surface resistivity”.
Pollution degree 1: No pollution or only dry, non-conductive
pollution occurs. The pollution has no influence.
Pollution degree 2: Normally only non-conductive pollution
occurs. Occasionally, however, a temporary conductivity caused
by condensation must be expected.
Pollution degree 3: Conductive pollution occurs, or dry, non-
conductive pollution occurs which becomes conductive due to
condensation which is expected. In such conditions, equipment
is normally protected against exposure to direct sunlight,
precipitation, and full wind pressure, but neither temperature
nor humidity is controlled.
Location: Indoor
Temperature: -25°C to 70°C
Relative Humidity: ≤90%(no condensation)
Do not dispose this instrument as unsorted
municipal waste. Please use a separate collection
facility or contact the supplier from which this
instrument was purchased. Please make sure
discarded electrical waste is properly recycled to
reduce environmental impact.
7

PSU Series User Manual
Power cord for the United Kingdom
When using the power supply in the United Kingdom, make sure
the power cord meets the following safety instructions.
NOTE: This lead/appliance must only be wired by competent persons
WARNING: THIS APPLIANCE MUST BE EARTHED
IMPORTANT: The wires in this lead are coloured in accordance with the
following code:
As the colours of the wires in main leads may not correspond with
the coloured marking identified in your plug/appliance, proceed
as follows:
The wire which is coloured Green & Yellow must be connected to
the Earth terminal marked with either the letter E, the earth symbol
or coloured Green/Green & Yellow.
The wire which is coloured Blue must be connected to the terminal
which is marked with the letter N or coloured Blue or Black.
The wire which is coloured Brown must be connected to the
terminal marked with the letter L or P or coloured Brown or Red.
If in doubt, consult the instructions provided with the equipment
or contact the supplier.
This cable/appliance should be protected by a suitably rated and
approved HBC mains fuse: refer to the rating information on the
equipment and/or user instructions for details. As a guide, a cable
of 0.75mm2 should be protected by a 3A or 5A fuse. Larger
conductors would normally require 13A types, depending on the
connection method used.
Any exposed wiring from a cable, plug or connection that is
engaged in a live socket is extremely hazardous. If a cable or plug is
deemed hazardous, turn off the mains power and remove the cable,
any fuses and fuse assemblies. All hazardous wiring must be
immediately destroyed and replaced in accordance to the above
standard.
8

GETTING STARTED
PSU Series Overview................................................ 10
Series lineup ...................................................................................... 10
Main Features ................................................................................... 11
Accessories ........................................................................................ 12
Appearance .............................................................. 15
PSU Series Front Panel ................................................................... 15
PSU Series Display and Operation Panel .................................... 18
Rear Panel .......................................................................................... 20
Theory of Operation ................................................ 23
Operating Area Description ........................................................... 23
CC and CV Mode ............................................................................ 24
Slew Rate ........................................................................................... 26
Bleeder Control ................................................................................ 26
Internal Resistance ........................................................................... 27
Alarms ................................................................................................ 28
Considerations .................................................................................. 29
Grounding ......................................................................................... 31
GETTING STARTED
This chapter describes the power supply in a
nutshell, including its main features and front /
rear panel introduction. After going through the
overview, please read the theory of operation to
become familiar with the operating modes,
protection modes and other safety considerations.
9

PSU Series User Manual
1
Minimum voltage guaranteed to 0.2% of rating voltage.
2
Minimum current guaranteed to 0.4% of rating current.
PSU Series Overview
Series lineup
The PSU series consists of 15 models, covering a number of
different current, voltage and power capacities:
10

Main Features
High power density: 1500W in 1U
Universal input voltage 85~265Vac, continuous
operation.
Output voltage up to 600V, current up to 200A.
Active power factor correction.
Parallel master/slave operation with active
current sharing.
Remote sensing to compensate for voltage drop
in load leads.
19” rack mounted ATE applications.
A built-in Web server.
OVP, OCP and OHP protection.
Preset memory function.
Adjustable voltage and current slew rates.
Bleeder circuit ON/OFF setting.
CV, CC priority start function. (Prevents
overshoot with output ON)
Supports test scripts.
Built-in RS-232/485, LAN and USB interface.
Analog output programming and monitoring.
Optional interfaces: GPIB, Isolated Voltage (0-
5V/0-10V) and Isolated Current (4-20mA)
programming and monitoring interface.
(Factory options)
GETTING STARTED
11

PSU Series User Manual
Qty.
Output terminal cover
Analog connector plug kit
Output terminal M8 bolt set
(6V~60V model)
1.8M, provide for some region
only)
User manual, Programming
manual
* CTC GW/INSTEK JAPAN
USE ,RoHS
Factory Installed
Options
Voltage programming isolated analog
interface
Current programming isolated analog
interface
Front Panel Filter Kit (Operation
Temperature is guaranteed to 40˚C)
Accessories
Before using the PSU power supply unit, check the package
contents to make sure all the standard accessories are included.
12

GETTING STARTED
Cable for 2 units of PSU-Series in
parallel mode connection
Bus Bar for 2 units of PSU-Series in
parallel mode connection
Joins a vertical stack of 2 PSU units
together. 2U-sized handles x2, joining
plates x2.
Cable for 3 units of PSU-Series in
parallel mode connection
Bus Bar for 3 units of PSU-Series in
parallel mode connection
Joins a vertical stack of 3 PSU units
together. 3U-sized handles x2, joining
plates x2.
Cable for 4 units of PSU-Series in
parallel mode connection
Bus Bar for 4 units of PSU-Series in
parallel mode connection
Joins a vertical stack of 4 PSU units
together. 4U-sized handles x2, joining
plates x2.
RS232 cable with DB9 connector kit.
It Includes RS232 cable with DB9
connector, RS485 used master cable
(gray plug), slave cable (black plug),
intermediate connector and end
terminal connector.
RS485 cable with DB9 connector kit.
It Includes RS485 cable with DB9
connector, RS485 used master cable
(gray plug), slave cable (black plug),
intermediate connector and end
terminal connector.
13

PSU Series User Manual
Rack-mount slides (General Devices
P/N: C-300-S-116-RH-LH)
USB Cable 2.0-A-B Type, Approx. 1.2M
Power Cord SJT 12AWG/3C, 3m MAX
Length, 105 ºC, RNB5-5*3P UL/CSA
type
Power Cord H05W-F 1.5mm2/3C, 3m
MAX Length, 105 ºC, RNB5-5*3P VDE
type
Power Cord VCTF 3.5mm2/3C, 3m
MAX Length, 105 ºC, RNB5-5*3P PSE
type
Certificate of traceable calibration
14

GETTING STARTED
Lock/Local PROT Function Test Set Output
Unlock ALM_CLR M 1 M 2 M 3
Shift
: Long Push
VSR LAN RMT ERR DLY ALM ISR M 1 M 2 M 3 RUN
C C
A
C V
V
VOLTAGE CURRENT
PSU 40-38
DC Power Supply
0 -40V / 0 - 38A
Voltage Current
2 3 4 5
Display Area
1
116 7 8 9 10 12 13
Used to turn the power on/off.
USB A port for data transfer,
loading test scripts etc.
Air inlet for cooling the inside of
the PSU series.
Used to set the voltage value or
select a parameter number in the
Function settings.
The display area shows setting values, output
values and parameter settings. The function LEDs
below show the current status and mode of the
power supply. See page 18 for details.
Used to set the current value or
change the value of a Function
parameter.
Appearance
PSU Series Front Panel
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PSU Series User Manual
Used to lock all front panel
buttons other than the Output
Button or it switches to local
mode.
(Long push) Used to unlock the
front panel buttons.
Used to set and display OVP, OCP
and UVL.
(Long push) Used to release
protection functions that have
been activated.
Used to configure the various
functions.
(+Shift) Used to recall the M1
setup.
(+Shift and hold) Used to save the
current setup to M1.
Used to run customized scripts for
testing.
(+Shift) Used to recall the M2
setup.
(+Shift and hold) Used to save the
current setup to M2.
Used to set and confirm the output
voltage and output current.
(+Shift) Used to recall the M3
setup.
(+Shift and hold) Used to save the
current setup to M3.
16

GETTING STARTED
Used to enable the functions that
are written in blue characters
below certain buttons.
Used to turn the output on or off.
Lights in green when the output is
on.
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PSU Series User Manual
VSR LAN RMT ERR DLY ALM ISR M 1 M 2 M 3 RUN
C C
A
C V
V
VOLTAGE CURRENT
Display Area
14 1516 17
18 19 20 21 22 23 24
25
26 27 28
Displays the voltage or the parameter number of a
Function parameter.
Displays the current or the value of a Function
parameter.
Lights in green during constant voltage mode.
Lights in green during constant current mode.
Lights up when CV Slew Rate Priority is enabled.
Lights up when the LAN interface is connected.
Lights in green during remote control.
Lights in red when an SCPI error has occurred.
The Output On/Off Delay indicator LED.
Lights in red when a protection function has been
activated.
PSU Series Display and Operation Panel
18

GETTING STARTED
Lights up when CC Slew Rate Priority is enabled.
Lights in green when the memory value are being
recalled or saved.
Lights in green when the memory value are being
recalled or saved.
Lights in green when the memory value are being
recalled or saved.
Lights up when a Test Script has been activated.
Only the ERR and ALM LED’s are red. All the others
are green.
19

Rear Panel
S LS SLSNC
REMOTE SENSE
ANALOG PROGRAMMING
RS485 / 232
OUT IN
LAN
DC OUTPUT
AC INPUT
L N
100 240V
2000VA MAX.
AC
47 63Hz
234 15678
9 10
6-60V models:
PSU 6-200, 8-180, 12.5-120,
80-600V models:
PSU 80-19, 100-15, 150-10,
S LS SLSNC
REMOTE SENSE
ANALOG PROGRAMMING
OUT IN
RS485 / 232
LAN
L N
AC INPUT
100 240V
2000VA MAX.
AC
47 63Hz
1 2 3 4 5 6 7 8
ISOLATED PROGRAMMING
0 – 5V / 0 – 10V
1 2 3 4 5 6 7 8
ISOLATED PROGRAMMING
4 – 20mA
15-100, 20-76, 30-50,
40-38, 50-30, 60-25
300-5, 400-3.8, 600-2.6
Output terminals for 6V to 60V
models.
Output terminals for 80V to 600V
models.
USB port for controlling the PSU
remotely.
PSU Series User Manual
20

GETTING STARTED
Ethernet port for controlling the
PSU remotely.
Two different types of cables can
be used for RS232 or RS485-based
remote control.
PSU-232: RS232 cable with DB9
connector kit.
PSU-485: RS485 cable with DB9
connector kit.
RJ-45 connector that is used to
daisy chain power supplies with
the Remote-IN port to form a
communication bus.
PSU-485S: Serial link cable with
RJ-45 shielded connector.
External analog control connector.
Compensation of load wire drop.
1 2 3 4 5 6 7 8
ISOLATED PROGRAMMING
0 – 5V / 0 – 10V
Blank sub-plate for standard
units.
Isolated Analog connector for
units equipped with Isolated
Current and Voltage
Programming and Monitoring
option.
GPIB connector for units
equipped with IEEE
programming option.
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PSU Series User Manual
Connectors for grounding the output (two
positions, shown in red).
L N
AC INPUT
100 240V
2000VA MAX.
AC
47 63Hz
22

GETTING STARTED
The PSU power supplies are regulated DC power
supplies with a high voltage and current output.
These operate in CC or CV mode within a wide
operating range limited only by the voltage or
current output.
The operating area of each power supply is
determined by the rated output power as well as
the voltage and current rating.
Below is a comparison of the operating areas of
each power supply.
PSU Series Operating Area (6-80V models)
Current (A)
Voltage (V)
20
38 76 120
120 1801608060 1000 140
0
10
20
30
200
200
40
50
60
25
6
20 40
PSU 6-200
PSU 8-180
PSU 12.5-120
PSU 15-100
PSU 20-76
PSU 30-50
PSU 40-38
PSU 50-30
PSU 60-25
PSU 80-19
80
180
15
12.5
8
30
40
50
80
10050196030
70
Theory of Operation
The theory of operation chapter describes the basic principles of
operation, protection modes and important considerations that
must be taken into account before use.
Operating Area Description
23

PSU Series User Manual
PSU Series Operating Area (100-600V models)
Current (A)
Voltage (V)
300
3.8 5 10
400
12 1686 10
0
14
0
100
200
300
15
600
400
500
600
2.6
100
150
PSU 100-15
PSU 150-10
PSU 300-5
PSU 400-3.8
PSU 600-2.6
42
CC and CV mode
Description
When the power supply is operating in constant
current mode (CC) a constant current will be
supplied to the load. When in constant current
mode the voltage output can vary, whilst the
current remains constant. When the load
resistance increases to the point where the set
current limit (I
SET
) can no longer be sustained the
power supply switches to CV mode. The point
where the power supply switches modes is the
crossover point.
When the power supply is operating in CV mode,
a constant voltage will be supplied to the load,
whilst the current will vary as the load varies. At
the point that the load resistance is too low to
maintain a constant voltage, the power supply will
switch to CC mode and maintain the set current
limit.
The conditions that determine whether the power
supply operates in CC or CV mode depends on
the set current (I
SET
), the set voltage (V
SET
), the load
CC and CV Mode
24

GETTING STARTED
resistance (RL) and the critical resistance (RC). The
critical resistance is determined by V
SET/ISET
. The
power supply will operate in CV mode when the
load resistance is greater than the critical
resistance. This means that the voltage output will
be equal to the V
SET
voltage but the current will be
less than I
SET
. If the load resistance is reduced to
the point that the current output reaches the I
SET
level, the power supply switches to CC mode.
Conversely the power supply will operate in CC
mode when the load resistance is less than the
critical resistance. In CC mode the current output
is equal to I
SET
and the voltage output is less than
V
SET
.
RL=R
C
RL<R
C
VSET
ISET
CV
CC
V
I
RL>R
C
Crossover
point
For loads that generate a transient surge voltage, VSET
must be set so that the surge voltage does not reach
the voltage limit.
For loads in which transient peak current flows, ISET
must be set so that the peak value does not reach the
current limit.
25

Slew Rate
The PSU has selectable slew rates for CC and CV
mode. This gives the PSU power supply the ability
to limit the current/voltage draw of the power
supply. Slew rate settings are divided into High
Speed Priority and Slew Rate Priority. High speed
priority mode will use the fastest slew rate for the
instrument. Slew Rate Priority mode allows for
user adjustable slew rates for CC or CV mode. The
rising and falling slew rate can be set
independently.
High Speed
Priority
mode
Slew rate =
Enabled
The PSU DC power supplies employ a bleed
resistor in parallel with the output terminals.
Bleed resistors are designed to dissipate the power
from the power supply filter capacitors when
power is turned off and the load is disconnected.
Without a bleed resistor, power may remain
charged on the filter capacitors for some time and
PSU Series User Manual
Bleeder Control
26

GETTING STARTED
be potentially hazardous.
In addition, bleed resistors also allow for smoother
voltage regulation of the power supply as the
bleed resistor acts as a minimum voltage load.
The bleed resistance can be turned on or off using
the configuration settings.
By default the bleed resistance is on. For battery
charging applications, be sure to turn the bleed
resistance off as the bleed resistor can discharge the
connected battery when the unit is off.
On the PSU, the internal resistance of the power
supply can be user-defined in software. (Internal
Resistance Setting, see the Normal Function
Settings on page 101.) When the internal resistance
is set it can be seen as a resistance in series with
the positive output terminal. This allows the
power supply to simulate power sources that have
internal resistances such as lead acid batteries.
By default the internal resistance is 0Ω.
Internal
Resistance Range
Internal Resistance Range
Internal Resistance
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PSU Series User Manual
Over voltage protection (OVP) prevents a high
voltage from damaging the load. This alarm can
be set by the user.
Over current protection prevents high current
from damaging the load. This alarm can be set by
the user.
Under voltage limit. This function sets a minimum
voltage setting level for the output. It can be set by
the user.
Over temperature protection for slave and master
board. OHP is a hardware protection function.
Only when the unit has cooled can the over
temperature protection alarms be cleared.
Master board over temperature protection.
Slave board over temperature protection.
Alarms
The PSU power supplies have a number of protection features.
When one of the protection alarms is tripped, the ALM icon on the
display will be lit and the type of alarm that has been tripped will
be shown on the display. When an alarm has been tripped the
output will be automatically turned off. For details on how to clear
an alarm or to set the protection modes, please see page 49.
28

GETTING STARTED
Sense alarm. This alarm will detect if the sense
wires have been connected to the wrong polarity.
Hardware over voltage protection. This is a
hardware OVP that is fixed at approximately
120% of the rated voltage output.
AC Fail. This alarm function is activated when a
low AC input is detected.
Fan failure. This alarm function is activated when
the fan RPMs drop to an abnormally low level.
Force Shutdown is not activated as a result of the
PSU series detecting an error. It is a function that
is used to turn the output off through the
application of a signal from the rear-panel analog
control connector when an abnormal condition
occurs.
Alarms are output via the analog control
connector. The alarm output is an isolated opencollector photo coupler output.
When the power supply switch is first turned on,
an inrush current is generated. Ensure there is
enough power available for the power supply
when first turned on, especially if a number of
units are turned on at the same time.
When the load has current peaks or is pulsed, it is
possible for the maximum current to exceed the
mean current value. The PSU power supply
Considerations
The following situations should be taken into consideration when
using the power supply.
29

PSU Series User Manual
ammeter only indicates mean current values,
which means for pulsed current loads, the actual
current can exceed the indicated value. For pulsed
loads, the current limit must be increased, or a
power supply with a greater capacity must be
chosen. As shown below, a pulsed load may
exceed the current limit and the indicated current
on the power supply ammeter.
Current limit
level
Measured
Ammeter
current
Reverse Current:
Regenerative load
When the power supply is connected to a
regenerative load such as a transformer or
inverter, reverse current will feed back to the
power supply. The PSU power supply cannot
absorb reverse current. For loads that create
reverse current, connect a resistor in parallel to the
power supply to bypass the reverse current. This
description only applies when the bleed resistance
is off.
PSU Load
Resistor
Reverse current
The current output will decrease by the amount of
current absorbed by the resistor.
Ensure the resistor used can withstand the power
capacity of the power supply/load.
30