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 0.75mm2 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.

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

V

W

Auto

DC + AC

TEMP

SENSE

W

4W

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

INPUT

V

W

This terminal is used for all
measurements except for DC/AC
current measurements.

GDM-8351 User Manual

14

COM Terminal

1000V

750V

500Vpk

INPUT

V W

COM

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

COM

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

V

W

SENSE

W

4W

COM

200Vpk

H I

LO

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

AVmm

HzWkM

WSFC

mdB

%

AVmm

HzWkM

WSFC

RMTMAXMINRELHOLDSMFAUTO4W2WDCAC

USBSTOnμFMEMRATIOUNCAL

n μ 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.

GETTING STARTED

21

Rear Panel

USB Device Port

Power Cord
Socket

RS232 Port

Digital I/O port

100

220

120

240

SER.NO. LABEL

50 / 60 Hz

15VA MAX.

LINE RATING

FUSE LINE

100VAC
120VAC

220VAC
240VAC

0.125AT

0.063AT

TEST LEADS BEFORE REPLACING FUSE

DISCONNECT POWER CORD AND

REMOVE INPUTS BEFORE OPENING.

TO AVOID SHOCK,

WARNING

DIGITAL I / O

RS232

H.F L.F PASS EOM

SET3SET2SET1 SET4

TRIG

IN

GND

Fuse 0.125AT/

0.063AT

Digital I/O Port

DIGITAL I / O

H.F L.F PASS EOM

SET3SET2SET1 SET4

TRIG

IN

GND

The Digital I/O port is
used for outputting the
comparison test results,
external triggering and
as a user-defined output
port. See page 89.

Power Cord
Socket

100

220

120

240

Accepts the power cord.
AC 100/120/220/240V
±10%, 50/60Hz

For power on sequence,
see page 24.

Fuse Socket

100

220

120

240

Holds the main fuse:

100/120 VAC: 0.125AT
220/240 VAC: 0.063AT

For fuse replacement
details, see page 141.

GDM-8351 User Manual

22

RS232

RS232

RS232 port. This port is used for
remote control. See page 94.

USB Device Port

Type B USB port. This port is used
for remote control. See page 94.

GETTING STARTED

23

Set Up

Tilting the Stand

From the base of the handle, gently pull the handle out sideways
and then rotate it to one of the following positions.

Horizontal
position

Tilt stand
position

Carry position

GDM-8351 User Manual

24

Power Up

Steps

1. Ensure the correct line

voltage is lined up with
the arrow on the fuse
holder. If not, see page 141
to set the line voltage and
fuse.

2. Connect the power

cord to the AC
voltage input.

Note

Make sure the ground connector on the power
cord is connected to a safety ground. This will
influence the measurement accuracy.

3. Push to turn on the main

power switch on the front
panel.

4. The display turns on and shows the last

function that was used before the power was
reset.

P

O

W

E

R

GETTING STARTED

25

How to Use the Instrument

Background

The following section will introduce to you
how to access the basic functions on the DMM
as well as how to navigate the menu system
and edit the parameter values.

Using the
Function keys

Any of the primary functions can be used by
simply pressing the desired function key.

For example:
To activate the DCV function, press the DCV
key.

DCV

DCI

To activate a secondary function, first press the
SHIFT key followed by the function key for the
secondary function.

For example: To activate DCI measurement,
first press the SHIFT key. SHIFT will be
highlighted on the display. Next, press the
DCV function key. This will activate the DCI
mode.

SHIFT

EXIT

→

DCV

DCI

GDM-8351 User Manual

26

Navigating the
Menu System

The menu system is navigated with the Up,
Down, Left and Right arrow keys, the
Auto/Enter key and the SHIFT/EXIT key.

SHIFT

EXIT

Auto

Enter

RANGE

RANGE

To enter the menu system, press the MENU
key. See page 139 for the System Menu tree.

MENU

dBm

 Pressing the Left and Right arrow keys will

navigate to each of the menu items on the
current menu level.

 Pressing the Down key will go down to the

next level of the menu tree.

 Conversely pressing the Up key will allow

you to go back to the previous menu level.

 Pressing Down or Enter on the last item in

a menu tree will allow you to edit the
settings or parameters for that particular
item or setting.

 Pressing the Exit key will allow you to exit

from the current settings and return to the
previous menu tree level.

GETTING STARTED

27

Editing a Setting
or Parameter

When you access a menu or parameter setting,
the Up, Down, Left and Right keys can be used
again to edit the parameter as well.

Auto

Enter

RANGE

RANGE

 If a setting or parameter is flashing, it

indicates that that particular parameter can
be edited.

 Pressing the Left or Right arrow key will

allow you to select a digit or character to
edit.

 Pressing the Up or Down keys will allow

you to edit the selected character.

GDM-8351 User Manual

28

OPERATION

Basic Measurement Overview .......................................... 30

Refresh Rate ............................................................... 30

Reading Indicator ....................................................... 31

Automatic/Manual Triggering ................................... 31

AC/DC Voltage Measurement .......................................... 32

Select the Voltage Range ........................................... 33

Voltage Conversion Table .......................................... 35

Crest Factor Table ...................................................... 36

AC/DC Current Measurement .......................................... 37

Select the Current Range ........................................... 39

Resistance Measurement ................................................. 42

Select the Resistance Range ...................................... 44

Diode Test ....................................................................... 45

Capacitance Measurement ............................................... 46

Select the Capacitance Range .................................... 47

Continuity Test ................................................................ 48

Set Continuity Threshold ........................................... 49

Continuity Beeper Settings ........................................ 50

Frequency/Period Measurement ...................................... 51

Frequency/Period Settings ........................................ 52

Temperature Measurement .............................................. 53

Set the Temperature Units ........................................ 54

Select Thermocouple Type ........................................ 55

OPERATION

29

Set the Reference Junction Temperature ................... 56

Dual Measurement Overview ........................................... 57

Supported dual measurement modes ....................... 57

Using Dual Measurement Mode ............................... 58

Advanced Measurement Overview ................................... 62

Supported Advanced Measurement Functions ........ 62

dBm/dB/W Measurement ................................................ 63

dBm/dB Calculation ................................................... 63

Measuring dBm/W .................................................... 63

Measure dB ................................................................ 65

Max/Min Measurement ................................................... 66

Relative Measurement ..................................................... 67

Hold Measurement ......................................................... 69

Compare Measurement ................................................... 70

Math Measurement ......................................................... 72

Math Measurement Overview ................................... 72

Measure MX+B .......................................................... 72

Measure 1/X ............................................................... 73

Measure Percentage................................................... 74

GDM-8351 User Manual

30

Basic Measurement Overview

Refresh Rate

Background

The refresh rate defines how frequently the
DMM captures and updates measurement data.
A faster refresh rate yields a lower accuracy. A
slower refresh rate yields a higher accuracy.
Consider these tradeoffs when selecting the
refresh rate.

For further details, please see the specifications.

Refresh rate
(Reading/S)

Function

S M F

Continuity/Diode

10

40

320

DCV/DCI

10

40

320

ACV/ACI

10

40

320

Frequency/Period

1

9.8

83

Temperature

10

40

320

Resistance

10

40

320

Capacitance

2 2 2

Steps

1. Press the left or right arrow keys to change the

refresh rate.

2. The refresh rate will be

shown at the top of the
display.

F ↔ M ↔ S

Note

The refresh rate cannot be set for capacitance
measurement.