GW Instek PSW 30-36, PSW 80-13.5, PSW 160-7.2, PSW 250-4.5, PSW 800-1.44 User guide
...
Multi-Range DC Power Supply
PSW Series
USER MANUAL
GW INSTEK PART NO. 82SW-80400MI1
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.
SAFETY INSTRUCTIONS
Table of Contents
SAFETY INSTRUCTIONS ................................................... 5
GETTING STARTED ........................................................... 9
PSW Series Overview ........................... 10
Appearance .......................................... 15
Theory of Operation ............................. 22
OPERATION .................................................................... 35
Set Up .................................................. 37
Basic Operation ................................... 57
Parallel / Series Operation ................... 72
Test Scripts .......................................... 87
CONFIGURATION ........................................................... 96
Configuration ....................................... 97
ANALOG CONTROL ....................................................... 116
Analog Remote Control Overview ....... 117
Remote Monitoring ............................ 133
COMMUNICATION INTERFACE ..................................... 138
Interface Configuration ...................... 139
MAINTENANCE ............................................................. 154
FAQ ............................................................................... 156
APPENDIX ..................................................................... 158
PSW Default Settings ......................... 158
Error Messages & Messages .............. 161
3
Table of Contents
LED Display Format ........................... 161
PSW Specifications ............................ 162
PSW Dimensions ............................... 177
Declaration of Conformity .................. 182
INDEX ............................................................................ 183
4
SAFETY INSTRUCTIONS
WARNING
Warning: Identifies conditions or practices that
could result in injury or loss of life.
CAUTION
Caution: Identifies conditions or practices that
could result in damage to the PSW or to other
properties.
DANGER High Voltage
Attention Refer to the Manual
Protective Conductor Terminal
Earth (ground) 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
PSW 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 PSW.
Avoid severe impact or rough handling that
leads to damaging the PSW.
Do not discharge static electricity to the PSW.
Use only mating connectors, not bare wires, for
the terminals.
Do not block the cooling fan opening.
Do not disassemble the PSW unless you are
qualified.
(Measurement categories) EN 61010-1:2010 and EN 61010-2-030
specify the measurement categories and their requirements as
follows. The PSW 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.
Power Supply
WARNING
AC Input voltage range: 85VAC~265VAC
Frequency: 47Hz~63Hz
To avoid electrical shock connect the protective
grounding conductor of the AC power cord to
an earth ground.
Safety Guidelines
6
SAFETY INSTRUCTIONS
Cleaning the PSW
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.
Operation
Environment
Location: Indoor, no direct sunlight, dust free,
almost non-conductive pollution (Note below)
Relative Humidity: 20%~ 85%
Altitude: < 2000m
Temperature: 0°C to 50°C
(Pollution Degree) EN 61010-1:2010 and EN 61010-2-030 specify the
pollution degrees and their requirements as follows. The PSW 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.
Storage
environment
Location: Indoor
Temperature: -25°C to 70°C
Relative Humidity: <90%, no condensation
Disposal
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
PSW Series User Manual
Green/ Yellow:
Earth
Blue:
Neutral
Brown:
Live (Phase)
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
PSW Series Overview ....................................................... 10
Series lineup .............................................................................................................. 10
Main Features ........................................................................................................... 11
Accessories ................................................................................................................ 12
PSW 30/80/160 Accessories .................................................................... 12
PSW 250/800 Accessories ........................................................................ 13
Appearance ..................................................................... 15
PSW Front Panel ..................................................................................................... 15
Rear Panel ................................................................................................................. 18
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
PSW Series User Manual
Note
Throughout the user manual, PSW 30, PSW 80,
PSW 160, PSW 250 or PSW 800 will refer to any of
the PSW models with a maximum voltage rating of
30V, 80V, 160V, 250V or 800V, respectively.
Model name
Type
Voltage Rating
Current Rating
Power
PSW 30-36
Type I
0~30V
0~36A
360W
PSW 80-13.5
Type I
0~80V
0~13.5A
360W
PSW 160-7.2
Type I
0~160V
0~7.2A
360W
PSW 250-4.5
Type I
0~250V
0~4.5A
360W
PSW 800-1.44
Type I
0~800V
0~1.44A
360W
PSW 30-72
Type II
0~30V
0~72A
720W
PSW 80-27
Type II
0~80V
0~27A
720W
PSW 160-14.4
Type II
0~160V
0~14.4A
720W
PSW 250-9
Type II
0~250V
0~9A
720W
PSW 800-2.88
Type II
0~800V
0~2.88A
720W
PSW 30-108
Type III
0~30V
0~108A
1080W
PSW 80-40.5
Type III
0~80V
0~40.5A
1080W
PSW 160-21.6
Type III
0~160V
0~21.6A
1080W
PSW 250-13.5
Type III
0~250V
0~13.5A
1080W
PSW 800-4.32
Type III
0~800V
0~4.32A
1080W
PSW Series Overview
Series lineup
The PSW series consists of 15 models, divided into 3 different
model types covering 3 power capacities: Type I (360 Watt), Type II
(720 Watt) and Type III (1080 Watt).
10
GETTING STARTED
360 Watt models
Type I
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30 -36
360W
Multi-Range DC Power Supply
Voltage
Current
720 Watt models
Type II
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30 -72
720W
Voltage
Current
Multi-Range DC Power Supply
1080 Watt models
Type III
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30 -108
1080W
Voltage
Current
Multi-Range DC Power Supply
Performance
High performance/power
Power efficient switching type power supply
Low impact on load devices
Fast transient recovery time of 1ms
Fast output response time
Features
OVP, OCP and OTP protection
Adjustable voltage and current slew rates
User adjustable bleeder control to quickly
dissipate the power after shutdown to safe
levels.
Extensive remote monitoring and control
options
Support for serial* and parallel connections.
*(30, 80, 160 volt models only)
Power on configuration settings.
Supports test scripts
Web server monitoring and control
Apart from the differences in output, each unit differs in size. The
720 and 1080 watt models are larger than the 360 watt models to
accommodate the increase in power.
Main Features
11
PSW Series User Manual
Interface
Ethernet port
Analog connector for analog voltage and current
monitoring
USB host and device port
Standard
Accessories
Part number
Description
CD-ROM
User manual,
programming manual
4323-30600101
Power cord (Type I/II)
4320-91001101
Power cord (Type III)
1042-SWLV0301
Output terminal cover
GTL-123
Test leads: 1x red, 1x black
GTL-240
USB Cable
PSW-004
Basic Accessory Kit:
M4 terminal screws and
washers x2, M8 terminal
bolts, nuts and washers x2,
Air filter x1, Analog control
protection dummy x1,
Analog control lock level x1
Optional
Accessories
Part number
Description
GET-001
Extended terminal
PSW-001
Accessory Kit:
Pin contact x10, Socket x1,
Protection cover x1
Accessories
Please check the contents before using the PSW.
PSW 30/80/160 Accessories
12
GETTING STARTED
PSW-002
Simple IDC
Tool
PSW-003
Contact
Removal Tool
PSW-005
Series operation cable for 2
units.
PSW-006
Parallel operation cable for
2 units.
PSW-007
Parallel operation cable for
3 units.
GRA-410-J
Rack mount adapter (JIS)
GRA-410-E
Rack mount adapter (EIA)
GUG-001
GPIB to USB adapter
GTL-240
USB Cable
57RG-30B00201
Large filter (Type II/III)
Download
Name
Description
psw_cdc.inf
USB driver
Standard
Accessories
Part number
Description
CD-ROM
User manual,
programming manual
4323-30600101
Power cord (Type I/II)
4320-91001101
Power cord (Type III)
1042-SWHV0301
High voltage output
terminal cover
GTL-240
USB Cable
39BT-50900401
High voltage output
terminal
PSW 250/800 Accessories
13
PSW Series User Manual
PSW-008
Basic Accessory Kit:
(Air filter x1, Analog control
protection dummy x1,
Analog control lock level x1
Optional
Accessories
Part number
Description
GET-002
Extended terminal
PSW-001
Accessory Kit:
Pin contact x10, Socket x1,
Protection cover x1
PSW-002
Simple IDC
Tool
PSW-003
Contact
Removal Tool
PSW-006
Parallel operation cable for
2 units.
PSW-007
Parallel operation cable for
3 units.
GRA-410-J
Rack mount adapter (JIS)
GRA-410-E
Rack mount adapter (EIA)
GTL-130
Test leads: 2x red, 2x black
GUG-001
GPIB to USB adapter
GTL-240
USB Cable
57RG-30B00201
Large filter (Type II/III)
Download
Name
Description
psw_cdc.inf
USB driver
14
GETTING STARTED
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30 -72
720W
Voltage
Current
Multi-Range DC Power Supply
Current
knob
Output
key
Power
switch
Voltage
knob
USB A
port
Display
Cover
panel
Function
keys
1080W: PSW 30-108, 80-40.5, 160-21.6,
250-13.5, 800-4.32
360W: PSW 30-36,
80-13.5, 160-7.2,
250-4.5, 800-1.44
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30- 108
1080W
Voltage
Current
Multi-Range DC Power Supply
A
W
V
W
%W10080604020
ISR
C C
DLY
ALM
RMT
C V
VSR
Function OVP/OCP Set
Output
PWR DSPLLock/LocalTest
PSW 30- 36
360W
Multi-Range DC Power Supply
Voltage
Current
Appearance
PSW Front Panel
720W: PSW 30-72, 80-27, 160-14.4, 250-9, 800-2.88
15
PSW Series User Manual
Function Keys
The Function keys along with the Output key will
light up when a key is active.
Function
The Function key is used to
configure the power supply.
OVP/OCP
Set the over current or over
voltage protection levels.
Set
Sets the current and voltage limits.
Test
Used to run customized scripts for
testing.
Lock/Local
Locks or unlocks the panel keys to
prevent accidentally changing
panel settings.
PWR DSPL
Toggles the display from viewing
V/A V/W or A/W*.
*Press the Voltage knob for V/W,
press the Current knob for A/W.
Display
Indicators
VSR
Voltage Slew Rate
C V
Constant Voltage Mode
RMT
Remote Control Mode
ALM
Alarm on
DLY
Delay Output
C C
Constant Current Mode
ISR
Current Slew Rate
16
GETTING STARTED
20 40 60
80 100 % W
Power bar
Indicates the current power output
as a percentage.
Voltage Knob
Voltage
Sets the voltage.
Current Knob
Current
Sets the current.
Output
Output
Press to turn on the output. The
Output key will light up when the
output is active.
USB
USB A port for data transfer,
loading test scripts etc.
Power Switch
Used to turn the power on/off.
17
PSW Series User Manual
Output
terminal
(+)
Fan
Output
terminal (-)
USB B
port
LAN
AC Input
Senseterminal
Analog control
connector
LAN
100 240V
1000VA MAX.
AC
47 63Hz
SER.NO. LABEL
Sense+
terminal
Chassis
ground
1080W: PSW 30-108, 80-40.5, 160-21.6
360W: PSW 30-36,
80-13.5, 160-7.2
100 240VAC
1500VA MAX.
47 63Hz
LAN
LN
SER.NO. LABEL
AC Input
LAN
100 240V
47 63Hz 500VA MAX.
AC
Rear Panel
720W: PSW 30-72, 80-27, 160-14.4
18
GETTING STARTED
LAN
100 240V
1000VA MAX.
AC
47 63Hz
SER.NO. LABEL
V SN.C. S V
Output
terminals +V
Fan
Chassis
ground
USB B
port
LAN
AC Input
Senseterminal
Analog control
connector
Sense+
terminal
Output
terminals -V
1080W: PSW 250-13.5, 800-4.32
360W: PSW 250-4.5,
800-1.44
LAN
LN
SER.NO. LABEL
47 63Hz
1500VA MAX.
AC100 240V
V VSN.C. S
AC Input
LAN
100 240V
47 63Hz500VA MAX.
AC
V SN.C. S V
720W: PSW 250-9, 800-2.88
19
PSW Series User Manual
Analog Control
Connector
Standard 26 pin MIL connector
(OMRON XG4 IDC plug).
The analog control connector is
used to monitor current and voltage
output, machine status (OVP, OCP,
OTP etc.), and for analog control of
the current and voltage output.
Use an OMRON XG5 IDC socket as
the mating socket.
Output Terminals
(30, 80, 160 volt
models)
Positive (+) and negative (-) output
terminals.
Chassis ground
Sense (-S) and Sense (+S) terminals.
Output Terminals
(250, 800 volt
models)
The 250 and 800 volt models use a 9 pin connector
and a plug for the output and sense terminal
connections. The plug is a MC420-38109Z plug by
DECA SwitchLab Inc. This plug is also available
separately (GW part number 39BT-50900401).
V SN.C. S V
Positive (V+) and negative (V-)
output terminals (3 of each).
V SN.C. S V
Chassis ground
V SN.C. S V
Sense (-S) and Sense (+S)
terminals.
20
GETTING STARTED
USB B port
The USB B port is used for remote
control.
Fans
Temperature controlled fans
Ethernet Port
LAN
The ethernet port is used for remote
control and digital monitoring from
a PC.
Line Voltage
Input
(Type I/TypeII)
Type I: PSW 30-36/80-13.5/
160-7.2/250-4.5, 800-1.44
Type II: PSW 30-72/80-27/
160-14.4/250-9, 800-2.88
Voltage Input: 100~240 VAC
Line frequency: 50Hz/60 Hz
(Automatically switchable)
Line Voltage
Input
(Type III)
LN
Type III:
PSW 30-108/80-40.5/160-21.6/
250-13.5/800-4.32
Voltage Input: 100~240 VAC
Line frequency: 50Hz/60 Hz
(Automatically switchable)
21
PSW Series User Manual
Background
The PSW 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 output power.
The operating area of each power supply is
determined by the rated output power as well
as the voltage and current rating. For example
the operating area and rated power output for
the PSW 30-36 is shown below.
Voltage
Current
30
360W rated power
10
12 36
PSW 30-36 Operating Area
When the power supply is configured so that
the total output (current x voltage output) is
less than the rated power output, the power
supply functions as a typical constant current,
constant voltage power supply.
If however, the power supply is configured
such that the total output (current x voltage
output) exceeds the rated power output, the
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
22
GETTING STARTED
effective output is actually limited to the power
limit of the unit. In this case the output current
and voltage then depend purely on the load
value.
Below is a comparison of the operating areas of
each power supply.
PSW 800V Series Operating Area
0
100
800
Current (A)
Voltage (V)
200
300
400
700
0
1
2
3
4
900
5
Type III
Type II
Type I
500
600
0.45 0.9 1.35
800
250
2.88 4.321.44
PSW 250V Series Operating Area
Current (A)
Voltage (V)
0
3
6
9
12
15
Type III
Type II
Type I
1.44 2.88 4.32
250
80
9 13.54.5
250
200
150
100
50
0
23
PSW Series User Manual
PSW 160V Series Operating Area
0
20
160
Current (A)
Voltage (V)
40
60
80
140
0
5
10
15
20
180
25
Type III
Type II
Type I
100
120
2.25 4.5 6.75
160
50
14.4 21.67.2
PSW 80V Series Operating Area
Current (A)
Voltage (V)
26.6
4.5 9.0 13.5
80
Type III
Type II
Type I
30
45
40205
10
15
25
0
35
0
20
40
60
80
90
27 40.5
24
GETTING STARTED
PSW 30V Series Operating Area
0
5
30
Current (A)
Voltage (V)
10
15
20
25
0 20
40
60
80
100
10
12 24 36
30
35
120
Type III
Type II
Type I
72 108
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
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
CC and CV Mode
25
PSW Series User Manual
(V
SET
), the load 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
26
Slew Rate
Theory
The PSW has selectable slew rates for CC and
CV mode. This gives the PSW 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
disables slew rate settings for CC or CV mode.
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.
Slew rate=
Disabled
Slew rate =
Enabled
Background
The PSW DC power supplies employ a bleed
resistor in parallel with the output terminals.
PSW
Load
Bleed
resistor
Bleed resistors are designed to dissipate the
power from the power supply filter capacitors
GETTING STARTED
Bleeder Control
27
PSW Series User Manual
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 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.
Note
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.
Background
On the PSW, the internal resistance of the
power supply can be user-defined in software.
(Internal Resistance Setting, page 105). 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.
Internal
Resistance Range
Unit Model
Internal Resistance Range
PSW 30-36
0.000 ~ 0.833Ω
PSW 30-72
0.000 ~ 0.417Ω
PSW 30-108
0.000 ~ 0.278Ω
PSW 80-13.5
0.000 ~ 5.926Ω
PSW 80-27
0.000 ~ 2.963Ω
PSW 80-40.5
0.000 ~ 1.975Ω
PSW 160-7.2
0.000 ~ 22.222Ω
PSW 160-14.4
0.000 ~ 11.111Ω
PSW 160-21.6
0.000 ~ 7.407Ω
Internal Resistance
28
GETTING STARTED
PSW 250-4.5
0.00 ~ 55.55Ω
PSW 250-9
0.00 ~ 27.77Ω
PSW 250-13.5
0.00 ~ 18.51Ω
PSW 800-1.44
0.0 ~ 555.5Ω
PSW 800-2.88
0.0 ~ 277.8Ω
PSW 800-4.32
0.0 ~ 185.1Ω
OVP
Overvoltage protection (OVP) prevents a high
voltage from damaging the load.
OCP
Overcurrent protection prevents high current
from damaging the load.
OTP
Over temperature protection protects the
instrument from overheating.
Power Switch Trip
When the Power Switch Trip configuration
setting is enabled, the power supply will
automatically shut down when a protection
setting has been tripped (OCP, OVP, OTP).
Alarm output
Alarms are output via the analog control
connector. The alarm output is an isolated
open-collector photo coupler output.
Alarms
The PSW power supplies have a number of protection features.
When one of the protection alarms are set, the ALM icon on the
display will be lit. For details on how to set the protection modes,
please see page 57.
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PSW Series User Manual
Inrush current
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.
Caution
Cycling the power on and off quickly can cause the
inrush current limiting circuit to fail as well as
reduce the working life of the input fuse and power
switch.
Pulsed or Peaked
loads
When the load has current peaks or is pulsed, it
is possible for the maximum current to exceed
the mean current value. The PSW power
supply 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.
Considerations
The following situations should be taken into consideration when
using the power supply.
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