EXTECH EX310 User Guide

User's Guide

Mini Multimeter

with Non-Contact Voltage Detector (NCV)

Model EX310

Introduction

Congratulations on your purchase of the Extech EX310 MultiMeter. The EX310
offers AC/DC Voltage, AC/DC Current, Resistance, Diode, and Continuity testing
plus a built-in non-contact Voltage Detector. Proper use and care of this meter
will provide many years of reliable service.

Safety

This symbol adjacent to another symbol, terminal or
operating device indicates that the operator must refer to
an explanation in the Operating Instructions to avoid
personal injury or damage to the meter.

WARNING

CAUTION

MAX
600V

This WARNING symbol indicates a potentially hazardous
situation, which if not avoided, could result in death or
serious injury.

This CAUTION symbol indicates a potentially hazardous
situation, which if not avoided, may result damage to the
product.

This symbol advises the user that the terminal(s) so
marked must not be connected to a circuit point at which
the voltage with respect to earth ground exceeds 600V.

This symbol adjacent to one or more terminals identifies
them as being associated with ranges that may, in normal
use, be subjected to particularly hazardous voltages. For
maximum safety, the meter and its test leads should not
be handled when these terminals are energized.

This symbol indicates that a device is protected
throughout by double insulation or reinforced insulation.

Model EX310-EU-ENG – V7.2– 05/2008

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SAFETY INSTRUCTIONS

This meter has been designed for safe use, but must be operated with caution.
The rules listed below must be carefully followed for safe operation.

1. NEVER apply voltage or current to the meter that exceeds the specified maximum:

Input Protection Limits

Function Maximum Input

V DC or V AC 600V AC and DC

mA AC/DC 200mA DC/AC

A AC/DC 10A DC/AC (for 30 seconds max. every 15

mins.)

Resistance, Diode Test,

250V DC/AC

Continuity

2. USE EXTREME CAUTION when working with high voltages.

3. DO NOT measure voltage if the voltage on the "COM" input jack exceeds 600V above earth
ground.

4. NEVER connect the meter leads across a voltage source while the function switch is in the
current, resistance, or diode mode. Doing so can damage the meter.

5. ALWAYS discharge filter capacitors in power supplies and disconnect the power when
making resistance or diode tests.

6. ALWAYS turn off power and disconnect test leads before opening the covers to replace the
fuse or battery.

7. NEVER operate the meter unless the back cover and the battery and fuse covers are in
place and fastened securely.

8. If the equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.

Model EX310-EU-ENG – V7.2– 05/2008

3

CAUTIONS

• Improper use of this meter can cause damage, shock, injury or death.
Read and understand this user manual before operating the meter.

• Always remove the test leads before replacing the battery or fuses.

• Inspect the condition of the test leads and the meter itself for any

damage before operating the meter.

• Use great care when making measurements if the voltages are greater
than 25VAC rms or 35VDC. These voltages are considered a shock
hazard.

• Always discharge capacitors and remove power from the device under
test before performing Diode, Resistance or Continuity tests.

• Voltage checks on electrical outlets can be difficult and misleading
because of the uncertainty of connection to the recessed electrical
contacts. Other means should be used to ensure that the terminals are
not "live".

• If the equipment is used in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired.

• This device is not a toy and must not reach children’s hands. It contains
hazardous objects as well as small parts that the children could swallow.
In case a child swallows any of them, please contact a physician
immediately

• Do not leave batteries and packing material lying around unattended;
they can be dangerous for children if they use them as toys

• In case the device is going to be unused for an extended period of time,
remove the batteries to prevent them from training

• Expired or damaged batteries can cause cauterization on contact with
the skin. Always, therefore, use suitable hand gloves in such cases

• See that the batteries are not short-circuited. Do not throw batteries into
the fire.

Model EX310-EU-ENG – V7.2– 05/2008

4

Controls and Jacks

1. AC Voltage Detector Sensor

2. AC Voltage Detector indicator light

3. LCD

4. Non-contact AC Voltage Detector
test button

5. Rotary function dial

6. 10 ampere test lead jack

7. COM test lead jack

8. Test lead jack for voltage, milliamp,
resistance/continuity, and diode
functions

9. Protective rubber holster (must be
removed to access the rear battery
compartment)

Symbols

•))) Continuity
Diode
Battery status

AC
DC
m milli (10
k kilo (10
V Volts
A Amps

Ω Ohms
AC Alternating current
DC Direct current

-3

) (volts, amps)

3

) (ohms)

1

2

3

9

4

5

EX310

MultiMeter

6

CATII-600V

V/ /mA

8

7

Model EX310-EU-ENG – V7.2– 05/2008

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