Extech MA460+ Operating Manual

User’s Guide

MiniAmp™ Series
Clamp-on Multimeters

Models:
MA400
MA420
MA440
MA460+

WARRANTY

EXTECH INSTRUMENTS CORPORATION warrants this
instrument to be free of defects in parts and workmanship for one
year from date of shipment (a six month limited warranty applies
on sensors and cables). If it should become necessary to return
the instrument for service during or beyond the warranty period,
contact the Customer Service Department at [phone] ext.
210 for authorization. A Return Authorization (RA) number must
be issued before any product is returned to Extech. The
sender is responsible for shipping charges, freight, insurance and
proper packaging to prevent damage in transit. This warranty does
not apply to defects resulting from action of the user such as
misuse, improper wiring, operation outside of specification,
improper maintenance or repair, or unauthorized modification.
Extech specifically disclaims any implied warranties or
merchantability or fitness for a specific purpose and will not be
liable for any direct, indirect, incidental or consequential damages.
Extech's total liability is limited to repair or replacement of the
product. The warranty set forth above is inclusive and no other
warranty, whether written or oral, is expressed or implied.

Copyright © 2001 Extech Instruments Corporation. All rights

reserved including the right of reproduction in whole or in

part in any form.

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MA Series V2.0 7/02

Introduction

Congratulations on your purchase of Extech model MA400,
MA420, MA440 or MA460+ clamp-on multimeter. Properly used,
this meter will provide many years of reliable service.

Clamp meter functions common to all meters:

Autoranging
AC Current Measurements
Data Hold
Auto Power Off
Maximum Hold captures 30ms peaks

1.1" (28mm) Jaw size

MultiMeter functions common to all models:

AC/DC Voltage to 600V
Resistance to 40MΩ
Capacitance and Frequency tests

Features unique to the MA440 and MA460+ models:

Twin 4000 count LCD displays
Simultaneous display of Current/Voltage, Current/Resistance, or
Current/Temperature (MA460+)

Features common to the MA400 and MA420 models:

Single 4000 count LCD display
Relative zero function
True rms (MA420) for current and voltage measurements

Safety

International Safety Symbols

Caution ! Refer to the explanation in this Manual

!

Warning ! Risk of electric shock

Earth (Ground)

Double Insulation or Reinforced insulation

Fuse

AC--Alternating Current

DC--Direct Current

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MA Series V2.0 7/02

Safety Precautions

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

2. Make sure any covers or battery doors are properly closed
and secured.

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

4. Inspect the condition of the test leads and the meter itself
for any damage before operating the meter. Repair or
replace any damage before use.

5. Do not exceed the maximum rated input limits.

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

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

8. Remove the battery from the meter if the meter is to be
stored for long periods.

9. To avoid electric shock, do not measure AC current on any
circuit whose voltage exceeds 600V AC.

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

11. The product is intended only for indoor use

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

13. Pollution degree: 2

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MA Series V2.0 7/02

PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY

OVERVOLTAGE CATEGORY I

Equipment of OVERVOLTAGE CATEGORY I is equipment for
connection to circuits in which measures are taken to limit the
transient overvoltages to an appropriate low level. Note –
Examples include protected electronic circuits.

OVERVOLTAGE CATEGORY II

Equipment of OVERVOLTAGE CATEGORY II is energy­consuming equipment to be supplied from the fixed installation.
Note – Examples include household, office, and laboratory
appliances.

OVERVOLTAGE CATEGORY III

Equipment of OVERVOLTAGE CATEGORY III is equipment in
fixed installations.
Note – Examples include switches in the fixed installation and
some equipment for industrial use with permanent connection to
the fixed installation.

OVERVOLTAGE CATEGORY IV

Equipment of OVERVOLTAGE CATEGORY IV is for use at the
origin of the installation.
Note – Examples include electricity meters and primary over­current protection equipment

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MA Series V2.0 7/02