GW Instek PEL-500 Series User manual

DC Electronic Load
PEL-500 Series
USER MANUAL
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
1
Table of Contents
SAFETY INSTRUCTIONS .................................................. 3
GETTING STARTED.......................................................... 7
PEL-500 Series Introduction ...................................... 9
Accessories.............................................................. 12
Accessories Installation Description ........................ 13
Operating Mode Description ................................... 15
Operating Area ........................................................ 20
APPEARANCE .......................................................... 22
Front Panel .............................................................. 22
Connecting the I-monitor to an oscilloscope ........... 55
LCD Display............................................................. 56
Rear Panel ............................................................... 63
INSTALLATION .............................................................. 64
Check line voltage.................................................... 65
Power up ................................................................. 66
USB & RS232 interface option ................................. 67
Load wire inductance............................................... 68
Input terminal and wire consideration ..................... 72
REMOTE CONTROL ....................................................... 75
Interface Configuration ............................................ 76
Communication Interface programming command
list ........................................................................... 78
Command Syntax ..................................................... 86
Command List ......................................................... 88
PRESET Commands ................................................. 91
Limit Commands ....................................................101
STAGE commands ..................................................103
System Commands .................................................109

PEL-500 User Manual
2
Measure Commands .............................................. 112
APPLICATION ...............................................................113
Local sense connections ........................................ 114
Remote sense connections .................................... 115
Constant Current mode application ....................... 117
Constant Resistance mode application .................. 121
Constant Voltage mode application ....................... 125
Constant Power mode application ......................... 128
Zero-Volt loading application................................. 132
PEL-500 series electronic load OCP, OPP, SHORT
operation flow Chart .............................................. 133
Power Supply OCP testing ..................................... 134
Power Supply OPP testing ..................................... 137
SHORT testing....................................................... 140
APPENDIX ....................................................................142
Replacing the Fuse................................................. 143
PEL-500 Default Settings ....................................... 144
PEL-500 Dimensions .............................................. 146
PEL-500 series Specifications ................................ 148
Declaration of Conformity...................................... 153

SAFETY INSTRUCTIONS
3
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.
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 instrument or to
other properties.
DANGER High Voltage
Attention Refer to the Manual
Earth (ground) Terminal
Frame or Chassis Terminal
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.

PEL-500 User Manual
4
Safety Guidelines
General
Guideline
CAUTION
Do not place any heavy object on the
instrument. Note: Only 2 units can be stacked
vertically.
Avoid severe impact or rough handling that
leads to damaging the instrument.
Do not discharge static electricity to the
instrument.
Use only crimped wires, not bare wires, for the
terminals.
Do not block the cooling fan opening.
Do not disassemble the instrument unless you
are qualified.
The equipment is not for measurements
performed for CAT II, III and IV.
(Measurement categories) EN 61010-1:2010 specifies the
measurement categories and their requirements as follows.
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.
Do NOT position the equipment so that it is
difficult to disconnect the appliance inlet or the
power plug.
If the equipment is used in a manner not
specified by the manufacturer, the protection
provided by the equipment may be impaired.

SAFETY INSTRUCTIONS
5
Power Supply
WARNING
AC Input voltage range: 115Vac / 230Vac ±10%
Frequency: 47-63Hz
To avoid electrical shock connect the protective
grounding conductor of the AC power cord to
an earth ground.
To avoid electric shock, the power cord
protective grounding conductor must be
connected to ground. No operator serviceable
components inside. Do not remove covers.
Refer servicing to qualified personnel.
Cleaning
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)
Temperature: 0°C to 40°C
Humidity: 0 to 85% RH
Altitude: <2000m
Overvoltage category II

PEL-500 User Manual
6
(Pollution Degree) EN 61010-1:2010 specifies the pollution degrees
and their requirements as follows. The instrument 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: -20°C to 70°C
Humidity: <90% RH
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.

GETTING STARTED
7
GETTING STARTED
More and more electronic products, such as mobile phones, laptops,
tablet chargers, mobile power supplies, wireless chargers, electric
hand tool chargers, etc., are currently using a single input voltage.
In response to this trend, Electronics introduced the single-machine
PEL-500 series of five electronic loads, including 80V and 500V,
350W and 700W four loads, and a 250W / 80V / 50A low wattage
load to meet the needs of various tests on the market. .
PEL-500 series electronic load continues the functions of various
electronic load modes, including constant current, constant
resistance, constant voltage, and constant power, dynamic and
short-circuits mode, high-precision 5bit voltage, current, and power
meter display simultaneously, full range RS232 and USB interfaces
are standard.
In addition, it also includes various complete performance tests for
battery CC, CP, timed discharge, etc., and Surge function for
simulating electronic product startup overcurrent and hot plugging
instantaneous current.
Each load module is capable of sinking a wide range of voltage and
current values. The load modules are limited by the maximum
power they can sink. For example the PEL-500 can sink up to 50A
and 80Vdc at a maximum of 250W. So if the maximum voltage of
80Vdc is present at the load’s input terminals a maximum load
current of 3.125A is possible. Conversely if the PEL-503-80-50 is
required to sink 50A the voltage must be limited to 5V.

PEL-500 User Manual
8
PEL-500 Series Introduction....................................... 9
Main Features .....................................................................................9
Protection features...........................................................................10
Accessories.............................................................. 12
Accessories Installation Description ........................ 13
Operating Mode Description ................................... 15
CC Mode ...........................................................................................15
CR mode............................................................................................15
CV mode............................................................................................16
CP mode ............................................................................................16
Slew Rate ...........................................................................................17
Dynamic Waveform Definition.....................................................18
Operating Area ........................................................ 20

GETTING STARTED
9
PEL-500 Series Introduction
Main Features
Features
5 digital V / A / W Meter.
High-speed measurement and communication
transmission.
V.A.W. values can be displayed
simultaneously.
Large LCD Display、setting values can be
adjusted by rotary knob or push button.
Short, OCP, OPP, Battery and Surge test
function.
Battery test function with stop condition: Vbatt,
Discharge capacity and discharge time.
Surge test with boot-on inrush simulation and
hot-swap simulation.
Flexible CC. CR, CV, CP, Dynamic and Short
operation modes.
SHORT time setting and SHORT_VH,
SHORT_VL setting function.
Protections against V, I, W, and °C.
Voltage meter display the polarity positive (“＋
“) or negative (“- “) is selectable.
Interface : RS232, USB

PEL-500 User Manual
10
Protection features
The protection features of the PEL-500 series Electronic load
modules are as follows:
Overvoltage
protection
The Electronic Load input will turn OFF if the
overvoltage circuit is tripped. The message OVP
will be displayed on the LCD. When the OVP fault
has been removed the load can be set to sink
power again. While the unit will attempt to
protect itself given an OVP state it is strongly
advised to guard against any potential OVP fault
state by using external protection and the correctly
rated electronic load.
The Overvoltage protection circuit is set at a
predetermined voltage and cannot be adjusted.
The OVP level is 105% of the PEL-500 series
nominal voltage rating.
Caution
Never apply an AC voltage to the input of the PEL-500
series Load. Do not apply a DC voltage that is higher
than PEL-500 series Load Module’s rating. If this
advice is ignored it is likely that damage will be caused
to the electronic load module. This damage will not be
covered by the warranty.
Over current
protection (OCP)
The OCP protection will engage if the current
being taken by the load reaches 105% of the load
module’s maximum current. The message OCP
will be displayed on the front panel and the unit
will switch to its LOAD OFF state. Once the source
of the over current has been removed the load can
be switched on again.
Over power
protection (OPP)
The PEL-500 series Electronic Load monitors the
power dissipation level. The input to the load is
automatically switched to LOAD OFF if the power
dissipation is greater than 105% of the rated power
input. If an over power condition occurs the
display will show OPP

GETTING STARTED
11
Over temperature
protection (OTP)
The load module’s internal temperature at the heat
sink is monitored. If the temperature reaches
approximately 90°C the OTP message will be
displayed and the unit will automatically switch to
the LOAD OFF state. If an OTP error occurs please
check the ambient temperature is between 0 to
40°C. Also ensure that the front and rear air vents
of the mainframe are not obstructed. The air flow
is taken from the front of the mainframe and
exhausted from the rear. Therefore a suitable gap
needs to be left at the rear of the mainframe. A
minimum of 15cm is recommended. After a
suitable cooling period the load can be switched.
Reverse Polarity
The PEL-500 series load module will tolerate a
reverse current up to the maximum current rating
of the load module. The ‘-‘symbol will be shown
on the voltage and current displays.
Please note that damage will occur if the reverse
current is higher than the load module’s maximum
rating. If a reverse current is noticed turn off and
disconnect the dc power source and turn the load
off. The connections between the DC Source and
the Load Module can now be correctly made.
Caution
If a reverse polarity situation occurs the load will sink
power even if the LOAD button is OFF. No current will
be displayed on the PEL-500 series load module.
Current up to the load’s maximum current rating will
be tolerated in reverse polarity. However there is no
OVP OCP and OPP protection. It is strongly
recommended that the load lines be fused if it is likely
that the load could be subject to reverse polarity.
These fuses should be fast acting and rated at the
maximum current of the load module +5%.

PEL-500 User Manual
12
Accessories
Item no.
Standard Accessories
Description
PCs
A
4mm Banana Plug (Red)
1
B
4mm Banana Plug (Black)
1
C
2mm Banana Plug (Red)
1
D
2mm Banana Plug (Black)
1
E
Hook Terminal Y type Large
size terminal
1
F
Hook Terminal Y type small
size terminal
4
G
BNC Cable
2
H
PEL-500 series User Manual
It can be downloaded from
GW Instek website
Optional Accessories
Description
USB Cable
GEL-246, 0.6m
1
RS-232 cable
GEL-238, 9pin, M-F Type,
1000mm
1

GETTING STARTED
13
Accessories Installation Description

PEL-500 User Manual
14

GETTING STARTED
15
Operating Mode Description
CC Mode
Background
With the operating mode of Constant Current, the
PEL-500 series electronic load will sink a current in
accordance with the programmed value regardless
of the input voltage
I
V
CC
LOAD
CURRENT
CURRENT SETTING
INPUT VOLTAGE
CR mode
Background
At Constant Resistance mode, the PEL-500 series
electronic load will sink a current linearly
proportional to the load input voltage in
accordance with the programmed resistance
setting
I
V
LOAD
CURRENT
INPUT VOLTAGE
RESISTANCE
SETTING

PEL-500 User Manual
16
CV mode
Background
At Constant Voltage mode, the PEL-500 series
electronic load will attempt to sink enough current
until the load input voltage reaches the
programmed value
I
V
LOAD
CURRENT
INPUT VOLTAGE
VOLTAGE
SETTING
CP mode
Background
At Constant Power mode, the PEL-500 series
electronic load will attempt to sink load power
(load voltage * load current) in accordance with
the programmed power.

GETTING STARTED
17
Slew Rate
Background
Slew rate is defined as the change in current or
voltage over time. A programmable slew rate
allows for a controlled transition from one load
setting to another. It can be used to minimize
induced voltage drops on inductive power wiring,
or to control induced transients on a test device
(such as would occur during power supply
transient response testing).
In cases where the transition from one setting to
another is large, the actual transition time can be
calculated by dividing the voltage or current
transition by the slew rate. The actual transition
time is defined as the time required for the input to
change from 10% to 90% or from 90% to 10% of the
programmed excursion.
In cases where the transition from one setting to
another is small, the small signal bandwidth (of the
load) limits the minimum transition time for all
programmable slew rates. Because of this
limitation, the actual transition time is longer than
the expected time based on the slew rate.
Rise Time
Transition
Limitation

PEL-500 User Manual
18
Therefore, both minimum transition time and slew
rate must be considered when determining the
actual transition time.
Following detail description is exclude in
operation manual. The minimum transition time
for a given slew rate as about a 30% or greater load
change, the slew rate increases from the minimum
transition time to the Maximum transition time at
a 100% load change. The actual transition time will
be either the minimum transition time, or the total
slew time (transition divided by slew rate),
whichever is longer.
Example
PEL-503-80-50
80V/50A/250W (CCH - CCL >50.4Ax 30%)
Use the following formula to calculate the
minimum transition time for a given slew rate Min
transition time=18A/slew rate (in amps/second).
7.56uS (15.12A/2) x 0.8(10%~90%) =6.048uS
Use the following formula to calculate the
maximum transition time for a given slew rate
Max transition time=60/slew rate (in
amps/second).
25.2uS (50.4A/2) x 0.8(10~90%) = 20.16uS
Example
CCH=10.08A, CCL=0A Slew Rate =2A/uS, the
expected time is 128uS but the actual transition
Time will be limited to 144uS
5.04uS (10.08A/2) x 0.8(10%~90%) = 4.032uS
Dynamic Waveform Definition
Background
Along with static operation the PEL-500 series
electronic load are built with a dynamic mode for
operation in Constant Current (CC), Constant
Resistance (CR) or Constant Power (CP). This