Extech EX520-S Instruction Manual

User's Guide

True RMS Industrial Multimeter

Extech EX520

Introduction

Congratulations on your purchase of the Extech EX520 True RMS Autoranging Multimeter.
This meter measures AC/DC Voltage, AC/DC Current, Resistance, Capacitance, Frequency
(electrical & electronic), Diode Test, and Continuity plus Thermocouple Temperature. It
features a rugged design for heavy duty use. 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
1000V

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 energy-consuming 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 over-current protection equipment

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 (in this case) 1000 VAC or VDC.

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.

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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.

• Warning! This is a class A equipment. This equipment can cause interferences in the
living quarters; in this case the operator can be required to carry out adequate
measures.

• 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 draining

• 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.

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EX520-EU_ENG V2.3 1/08

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 1000VDC/AC rms

mA AC/DC 800mA 1000V fast acting fuse

A AC/DC

Frequency, Resistance, Capacitance,
Diode Test, Continuity

Temperature 1000VDC/AC rms

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 the power and disconnect the test leads before opening the covers to
replace the fuse or batteries.

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.

10A 1000V fast acting fuse (20A for 30 seconds
max every 15 minutes)

1000VDC/AC rms

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Controls and Jacks

1. 6,000 count LCD

2. RANGE button

3. Hz and % button

4. Mode button

5. Function switch

6. mA, µA and 10A input jacks

7. COM input jack

8. Positive input jack

9. HOLD and Backlight button

10. RELATIVE button

11. MAX/MIN button

Note: Tilt stand and battery compartment are
on rear of unit.

Symbols and Annunciators

Auto power off

•))) Continuity
Diode test

Battery status

n nano (10
µ micro (10
m milli (10
A Amps
k kilo (10
F Farads (capacitance)
M mega (10
Ω Ohms
Hz Hertz (frequency) V Volts
% Percent (duty ratio) REL Relative
AC Alternating current AUTO Autoranging
DC Direct current HOLD Display hold
ºF Degrees Fahrenheit ºC Degrees Centigrade
MAX Maximum MIN Minimum

-9

) (capacitance)

-6

) (amps, cap)

-3

) (volts, amps)

3

) (ohms)

6

) (ohms)

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