GW Instek GDM-8351 User manual

Dual Measurement Multimeter
GDM-8351
USER MANUAL
GW INSTEK PART NO. 82DM-83510E01
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
3
Table of Contents
SAFETY INSTRUCTIONS ................................................... 5
GETTING STARTED ......................................................... 10
Characteristics ..........................................11
Appearance ...............................................13
Set Up.......................................................23
OPERATION.................................................................... 28
Basic Measurement Overview ...................30
AC/DC Voltage Measurement....................32
AC/DC Current Measurement ...................37
Resistance Measurement ..........................42
Diode Test ................................................45
Capacitance Measurement ........................46
Continuity Test ..........................................48
Frequency/Period Measurement ...............51
Temperature Measurement .......................53
Dual Measurement Overview ....................57
Advanced Measurement Overview ............62
dBm/dB/W Measurement .........................63
Max/Min Measurement.............................66
Relative Measurement ..............................67
Hold Measurement ...................................69
Compare Measurement .............................70
Math Measurement...................................72
SYSTEM/DISPLAY CONFIGURATION .............................. 76
View Serial Number ..................................77
View Version Number ...............................77
Brightness Settings ...................................78
Input Resistance Settings .........................79

GDM-8351 User Manual
4
Frequency/Period Input Jack Settings........80
Digital Filter..............................................81
Restore Factory Default Settings ...............85
Trigger ......................................................86
DIGITAL I/O.................................................................... 88
Digital I/O Overview .................................89
REMOTE CONTROL ........................................................ 93
Configure Remote Control Interface ..........94
Return to Local Control.............................98
COMMAND OVERVIEW .................................................. 99
Command Syntax ......................................99
Command List.........................................103
FAQ ...............................................................................138
APPENDIX .....................................................................139
System Menu Tree ...................................139
Factory Default Settings ..........................140
Replacing the AC Source Fuse .................141
Replacing the Input Fuse.........................142
Status system .........................................144
Specifications .........................................145
Additional Specifications ........................150
Dimensions ............................................156
Declaration of Conformity .......................157
INDEX............................................................................158

SAFETY INSTRUCTIONS
5
SAFETY INSTRUCTIONS
This chapter contains important safety instructions that you
must follow during operation and storage. Read the following
before any operation to ensure 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 DMM or to other
properties.
DANGER High Voltage
Attention Refer to the Manual
Protective Conductor Terminal
Earth (ground) 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.

GDM-8351 User Manual
6
Safety Guidelines
General Guideline
CAUTION
Make sure that the voltage input level does not
exceed DC1000V/AC750V.
Make sure the current input level does not
exceed 12A.
Do not place any heavy object on the
instrument.
Avoid severe impact or rough handling that can
lead to damaging the instrument.
Do not discharge static electricity to the
instrument.
Use only mating connectors, not bare wires, for
the terminals.
Do not block or obstruct the cooling fan vent
opening.
Do not perform measurement at the source of a
low-voltage installation or at building
installations (Note below).
Do not disassemble the instrument unless you
are qualified as service personnel.
Make sure that the COM terminal to earth is
limited to 500Vpk.
Remove all test leads before disconnecting the
mains power cord from the socket.
(Note) EN 61010-1:2010 specifies the measurement categories and
their requirements as follows. The GDM-8351 falls under category II
600V.
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.

SAFETY INSTRUCTIONS
7
Power Supply
WARNING
AC Input voltage: 100/120/220/240 V AC
50/60Hz
The power supply voltage should not fluctuate
more than 10%.
Connect the protective grounding conductor of
the AC power cord to an earth ground, to avoid
electrical shock.
Fuse
WARNING
Fuse type: 0.125AT 100/120VAC
0.063AT 220/240 VAC
Make sure the correct type of fuse is installed
before power up.
To avoid risk of fire, replace the fuse only with
the specified type and rating.
Disconnect the power cord before fuse
replacement.
Make sure the cause of a fuse blowout is fixed
before fuse replacement.
Cleaning the
Instrument
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 50°C
Humidity: 0~35°C: < 90%RH
>35°C: <80%RH
Altitude: <2000m

GDM-8351 User Manual
8
(Note) EN 61010-1:2010 specifies the pollution degrees and their
requirements as follows. The GDM-8351 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: -40°C to 70°C
Humidity: 0~35°C: <90%RH
>35°C: <80%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.

SAFETY INSTRUCTIONS
9
Power cord for the United Kingdom
When using the unit 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:
Green/ Yellow:
Earth
Blue:
Neutral
Brown:
Live (Phase)
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 0.75mm2should 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.

GDM-8351 User Manual
10
GETTING STARTED
This chapter describes the GDM-8351 multimeter in a nutshell,
including accessories, package contents, its main features and
front / rear panel introduction.
Characteristics ................................................................ 11
Accessories................................................................. 12
Appearance ..................................................................... 13
GDM-8351 Front Panel.............................................. 13
Display Overview ....................................................... 19
Rear Panel .................................................................. 21
Set Up............................................................................. 23
Tilting the Stand......................................................... 23
Power Up.................................................................... 24
How to Use the Instrument....................................... 25

GETTING STARTED
11
Characteristics
The GDM-8351 is a portable, dual-display digital multimeter
suitable for a wide range of applications, such as production testing,
research, and field verification.
Performance
DCV accuracy: 0.012%
High current range: 10A
High Voltage range: 1000V
High ACV frequency response: 100kHz
Features
The fastest sampling rate is (320 Readings / sec)
for ADC and PC transmission.
The diode test open-circuit voltage is ≑
6V/1mA.
120000 count display
Multiple functions: ACV, DCV, ACI, DCI, 2WR,
4WR, Cap, Freq, Period ,Temp, Continuity,
Diode test, MAX/MIN, Avg, REL, dB, dBm,
Hold, MX+B, 1/X, REF, %, Compare.
Manual or Auto ranging
AC true RMS
Data logging to PC using an Excel Add-In.
Interface
USB device port supports USBCDC and
USBTMC.
RS232
Digital I/O port can used in either pass/fail
testing (Compare function) or have the output
state remotely controlled. Only one function at a
time can be used.
Software
Excel Addins
LABVIEW driver

GDM-8351 User Manual
12
Accessories
Standard
Accessories
Part number
Description
82DM-83510E x1
CD-ROM (User Manual,
Software, Driver)
82DM-83511M x1
Safety Instruction Sheet
GTL-207
Test leads
Optional
Accessories
Part number
Description
GTL-246
USB Cable, USB 2.0, A-B type,
1200mm
GTL-205
Temperature Probe Adapter with
Thermal Coupling (K-type)

GETTING STARTED
13
Appearance
GDM-8351 Front Panel
DCV ACV /2W/4W Hz/P 2ND
REL MX/MN HOLD FILTER MENU EXIT
SHIFT
RANGE
RANGE
Enter
POWER
GDM-8351 120000 Counts Dual Measurement Multimeter
DCI ACI dB LOCAL
REL# MATH COMP TYPE
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
VW
Auto
DC + AC
TEMP
SENSE
W4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
dBm
Function keys
Sense LO TerminalPower Switch
Main Display
DC/AC 1A
Terminal,
1.25A/1000V
Fuse Holder
COM
Terminal
Arrow keys
DC/AC 10A Terminal
Sense HI Terminal
V
Terminal
W
Power Switch
POWER
Turns On or Off the main
power. For the power up
sequence, see page 24.
Main Display
Shows measurement results and parameters. For
display configuration details, see page 78
(brightness setting).
For an overview of the main display, see page 19.
W
V
Input
Terminal
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
VW
SENSE
W4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
This terminal is used for all
measurements except for DC/AC
current measurements.

GDM-8351 User Manual
14
COM Terminal
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
V W
SENSE
W 4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
Accepts ground (COM) line in all
measurements.
The maximum withstand voltage
between this terminal and earth is
500Vpk.
DC/AC 1A
Terminal
AMPS Fuse
Holder
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
V W
SENSE
W 4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
Low current measurement
terminal. Accepts DC/AC Current
input. For details see page 37.
DC: 10mA~1A
AC: 10mA~1A
As a fuse, protects the instrument
from over-current. Rating: F1.25A,
1000V.(This terminal accepts
DC/AC current input)
For the fuse replacement
procedure, see page 142.
DC/AC 10A
Terminal
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
V W
SENSE
W 4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
High range current measurement
terminal. Accepts DC/AC Current
input. For DCI or ACI details, see
page 37.

GETTING STARTED
15
Sense HI
Terminal
1000V
750V
500Vpk
INPUT
FUSE
1.25A/1000V
VW
SENSE
W4W
COM
200Vpk
H I
LO
10A 1A
CAT II 600V
Accepts HI sense line in 4W
resistance measurement.
Sense LO
Terminal
Accepts LO sense line in 4W
resistance measurement.
Measurement
Keys
The top row of measurement keys are used for
basic DMM measurements such as voltage,
current, resistance, capacitance and frequency. The
bottom row of measurement functions are used for
more advanced functions.
Each key has a primary and secondary function.
The secondary function is accessed in conjunction
with the SHIFT key.
Upper Measurement keys
DCV
DCV
DCI
Measures DC Voltage (page 32).
DCI
(SHIFT→DCV)
SHIFT
EXIT
→
DCV
DCI
Measures DC Current (page
37).
ACV
ACV
ACI
Measures AC Voltage (page 32).
ACI
(SHIFT→ACV)
SHIFT
EXIT
→
ACV
ACI
Measures AC Current (page
37).

GDM-8351 User Manual
16
DCV + ACV
DCV
DCI
+
ACV
ACI
Measures DC + AC voltage
(page 32).
DCI+ACI
SHIFT
EXIT
→
DCV
DCI
+
ACV
ACI
Measures DC +
AC current
(page 37).
2W/4W
2W/4W
TEMP
Measures resistance (2W or 4W)
See page 42.
TEMP
(SHIFT →
2W/4W)
SHIFT
EXIT
→
2W/4W
TEMP
Measures temperature. See
page 53.
/
/
Measures diodes or continuity,
depending on the selected mode.
See page 45 and 48, respectively.
(SHIFT→/)
SHIFT
EXIT
→
/
Measures capacitance. See
page 46.
Hz/P
Hz/P
dB
Measures the frequency or period
of a signal, depending on the
selected mode. See page 51.
dB
(SHIFT →Hz/P)
SHIFT
EXIT
→
Hz/P
dB
Measures dB. See page 65.

GETTING STARTED
17
2ND
2ND
LOCAL
As the 2ND key, selects the
measurement item on the 2nd
display (page 57). Pressing and
holding for more than 1 second
turns off the 2nd display.
As the Local key, releases the unit
from remote control and returns
the instrument to local panel
operation (page 97).
Lower Measurement keys
REL
REL
REL#
Measures the Relative value (page
67).
REL#
(SHIFT→REL)
SHIFT
EXIT
→
REL
REL#
Manually sets the reference
value for the Relative value
measurement.
MX/MN
MX/MN
MATH
Measures the Maximum or the
Minimum value (page 66).
MATH
(SHIFT→
MX/MN)
SHIFT
EXIT
→
MX/MN
MATH
Enters the Math
measurement mode. The
supported math functions
include MX+B, REF% and
1/X. See page 72 for details.
HOLD
HOLD
COMP
Activates the Hold function (page
69).

GDM-8351 User Manual
18
COMP
(SHIFT→HOLD)
SHIFT
EXIT
→
HOLD
COMP
Activates the compare
measurement function. See
page 70.
FILTER
FILTER
TYPE
Turns the digital filter on or off.
See page 81.
TYPE
(SHIFT→FILTER)
SHIFT
EXIT
→
FILTER
TYPE
Sets the type of filter and
the size of the rolling
window. See page 82.
MENU
MENU
dBm
Enters the configuration menu for
System Settings, Measurement
Settings, Temperature
measurement settings, I/O
settings, Terminal character
settings and Firmware installation.
See page 76 for the system menu.
dBm
(SHIFT→MENU)
SHIFT
EXIT
→
MENU
dBm
Measures dBm/W, see
page 63.
SHIFT/EXIT
SHIFT
EXIT
When used as a SHIFT key, it is
used to access the secondary
functions associated with the
measurement keys.
When used as an EXIT key, it will
exit out of menu systems.

GETTING STARTED
19
AUTO/ENTER
Auto
Enter
When used as an AUTO key, it
will set the range of the selected
function to autorange.
When used as an ENTER key, it
will confirm the entered value or
menu item.
Arrow Keys
RANGE
RANGE
The arrow keys are used to
navigate the menu system and edit
values.
The Up and Down arrow keys will
also manually set the range for the
voltage and current
measurements.
The Left and Right arrow keys will
also toggle the refresh rate
between the fast, medium and
slow (F, M, S) rates.
Display Overview
Primary Display
Secondary Display
Function status icons
Secondary
measurement units
Primary measurement units
Primary measurement
function icons
Secondary
measurement
function icons
REARGPIBUSBLANRS232FILTRCLSTOCOMP2ND dBmEXTSHIFTERRLIMITAUTOMATH4W2WDCAC AVmmHzWkM WSFC mdB
%
AVmmHzWkM WSFC
RMTMAXMINRELHOLDSMFAUTO4W2WDCAC USBSTOnμFMEMRATIOUNCAL nμ F
120000 Counts Dual Measurement Multimeter
GDM-8351
Primary Measurement
Function Icons
Displays the primary measurement
function.

GDM-8351 User Manual
20
Primary Measurement
Units
Displays the units for the primary
measurement function.
Secondary Display
Displays the results of the secondary
measurement.
Secondary Measurement
Units
Displays the units for the secondary
measurement function.
Secondary Measurement
function icons
Displays the secondary measurement
function.
Function Status Icons
Display status icons for
operations/functions that are not linked to
the primary or secondary functions.
Primary Display
Displays the results of the primary
measurement.