Mastech MS8239B User manual

MASTECH®
MS8239B
DIGITAL MULTIMETER
USER’S MANUAL

1
TABLE OF CONTENT
LIMITED WARRANTY AND LIMITATION OF
LIABILITY ...................錯誤! 尚未定義書籤。
Out of the Box ................................................ 3
Accessories .....................................................4
Certification....................................................7
INTRODUCTION ........................................... 7
Overview ........................................................7
Figures and Components................................7
Buttons and Components............................8
Display Description ................................... 10
USING THE METER..................................... 11
Preparation ...............................................11
DC/AC Voltage Measurement...................12
AC/DC Current Measurement ...................13
Resistance Measurement..........................15
Diode......................................................... 16
Continuity.................................................. 16
1.5V 9V and 12V Battery Test ...................17

2
SPECIFICATIONS ........................................ 18
General Specification ...................................18
Technical Specifications ...............................19
MAINTENANCE AND REPAIR ..................... 23
Repair........................................................23
Test Leads Replacement...............................24
Replacing Batteries .....................................25
Replacing Fuse .............................................25

3
LIMITED WARRANTY AND
LIMITATION OF LIABILITY
This MS8239B product from MASTECH will be free from
defects in material and workmanship for one year from
the date of purchase. This warranty does not cover
fuses, disposable batteries, or damage from drops,
neglect, misuse, alteration, contamination, or abnormal
conditions of operation or handling. Resellers are not
authorized to extend any other warranty on MASTECH’s
behalf. To obtain service during the warranty period,
contact your nearest MASTECH authorized service
center to obtain return authorization information and
then send the product to that Service Center with a
description of the problem.
Out of the Box
Check the Meter and accessories thoroughly before using
the Meter. Contact your local distributor if the Meter or
any components are damaged or malfunction.

4
Accessories
Test Leads 1set
1.5V AAA Battery 2pcs
User’s Manual
Safety Information
WARNING
TO REDUCE THE RISK OF FIRE, ELECTRICAL SHOCK,
PRODUCT DAMAGE OR PERSONAL INJURY, PLEASE
FOLLOW THE SAFETY INSTRUCTIONS DESCRIBED IN THE
USER’S MANUAL. READ THE USER’S MANUAL BEFORE
USING THE METER.
WARNING
TO ENSURE SAFE OPERATION AND LIFE OF THE METER,
DO NOT PLACE THE METER IN ANY ENVIRONMENT WITH
HIGH PRESSURE, HIGH TEMPERATURE, DUST, EXPLOSIVE
GAS OR VAPOR.

5
Avoid shaking, dropping or any kind of
impacts when using or transporting the Meter.
To avoid electric shock or personal injury,
repairs or servicing not covered in this manual
should be performed only by qualified
personnel.
Avoid direct exposure to sunlight to ensure
extended life of the Meter.
Do not place Meter in a strong magnetic field;
this may cause false readings.
Use only the batteries indicated in the
Technical Spec.
Avoid exposing batteries to humidity. Replace
batteries as soon as the low battery indicator
appears.
Please keep the original packing for future
shipping purposes (ex. Calibration)
After opening the box, check for any damage
during delivery.

6
Safety Symbols on the Meter
Important safety information, please refers
to the user manual
Earth ground
Indicates compliance with requirements for
double insulation
Possible of high voltage
Fuse must be replaced with ratings specified
in the manual.
Important Safety Information
Never use the Meter to measure voltages that
might exceed 600V DC/AC above earth
ground.
Always be careful when working with voltages
above 60V DC or 30V AC RMS. Keep fingers
behind the probe barriers while measuring.
Never connect the Meter leads across a
voltage source while the rotary switch is in
the resistance, diode or continuity mode.
Doing so can damage the Meter.
Do not perform resistance, diode and
continuity measurements on powered circuits.

7
Inspect test leads and probes for cracks,
breaks or crazes on the insulation before
using the Meter.
Repair or maintenance should be
implemented by trained personnel.
Certification
CAT III: This meter has meet IEC61010-1
standard with an overvoltage category (600V
CAT III) and pollution degree 2.
The Meter is compiled to EMC
requirements.
Introduction
Overview
The MS8239B is a compact and portable multifunction
digital multimeter featuring an easy-to-read LCD screen.
Basic functions include: AC/DC voltage, AC/DC current,
resistance, diode, continuity measurements and battery
test. This MS8239B is ideal for any entry level use.

8
Figures and Components
Buttons and Components
1. LCD (liquid-crystal display)
2. HOLD Button
3. Rotary Switch
4. 10A Input Jack
5. COM Input Jack
6. mA/V/Ω/ Input Jack

9
Front Panel
6
5
4
3
2
1