Megger WM6 Instruction Manual

Wee MEGGER®Te s t e r

W M 6

User Guide
Guide de l’utilisateur
G e b r a u c h s a n l e i t u n g
Guía del usuario

MEGGER

®

SAFETY WARNINGS

★ The circuit must be de-energized and isolated BEFORE connections are

made for any test.

★ Do not touch the circuit during an insulation test.
★ After insulation tests, capacitive circuits MUST be allowed to discharge

BEFORE disconnecting the test leads.

★ Test leads, including prods and crocodile clips, must be in good order;

clean and having no broken or cracked insulation.

★ Replacement fuses must be of the correct type and rating.
Refer also to page 8 for further explanations and other precautions.
The warnings and precautions must be read and understood before the

instrument is used. They must be observed during use.

NOTE

This instrument must only be used by suitably trained and competent persons.

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CONTENTS

Safety Warnings 2
General Description 4
Applications 4
Specification 5
Accessories 7
Operation 8

Warning 8
Preliminary checks 8
Fuse replacement 8
Insulation testing 9
Continuity testing 9

Using the Insulation Tester 10

Preventive maintenance 10
Insulation Testing concepts 11

Mode d’Emploi 12
Betriebsanleitung 14
Instrucciones de Uso 16
Setting-up Procedure 18
Repair and Warranty 19

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GENERAL DESCRIPTION APPLICATIONS

The WM6 MEGGER®Insulation and Continuity Tester
is a completely self contained instrument designed to
give rapid and accurate measurement of insulation
resistance and continuity resistance.

The WM6 uses a low voltage hand-cranked a.c.
brushless generator as the power supply. This
generator is easy to turn and is connected to a
rectifier and d.c. to d.c. converter to provide the test
voltage.

The WM6 uses a moving coil meter with taut band
suspension, white scales on a black scale plate and
an orange ‘dayglow’ pointer. An electronic circuit is
employed to produce a four decade calibrated scale
for insulation resistance measurement from 0 to
200 MΩ.

Two shrouded sockets are provided in the side of the
case for the test leads and a slider switch selects
either insulation or continuity tests (‘MΩ’ or ‘Ω’). The
case is robust, made of ABS plastic, and the
generator handle folds neatly against it when not in
use.

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The WM6 is intended for the direct measurement of
insulation resistance and continuity of domestic and
industrial wiring, cables, transformers, motors,
generators, electrical machinery and appliances.
Because the WM6 is self-powered it is suitable for
use during installation and commissioning work as
well as for service and maintenance applications.

Note:— The cover of this instrument has been given

an antistatic treatment which should be
effective for many months. If in the course of
time the cover is found to retain electrostatic
charges, it should be re-treated with a
suitable antistatic solution.

SPECIFICATION

Ranges insulation 0–200 MΩ and ∞

WM6

continuity 0–100 Ω

Terminal Voltage insulation range <600 V
on Open Circuit (d.c.) continuity range 800 mV approx.

Terminal Voltage at insulation range 500 V + 10% –5%
1 M Load (d.c.)

Terminal Current insulation range 1,3 mA approx.
on Short Circuit continuity range 55 mA approx.

Voltage Stability insulation range <±1%
160 r.p.m. to 240 r.p.m.

Ripple Content at 160 r.p.m. insulation range 500 mV pk-pk approx.
on Open Circuit

Accuracy 1,5 mm (0,060 in) from any marked position on the

scale when measured against standard resistors.

Temperature operating –10 °C to +50 °C

storage –20 °C to +70 °C

Flash Test 2,3 kV a.c. r.m.s.
Voltage Source (d.c.) Brushless a.c. hand-cranked generator with

rectifier and d.c. to d.c. converter.

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SPECIFICATION

Fuse 1 A 20 x 5 mm ceramic
Dimensions 131 x 98 x 61 mm (51/8 x 37/8 x 23/8 in)
Weight 650 g (1 lb 7 oz)
Terminal Voltage Characteristics

WM6

6

Ω

SPECIFICATION ACCESSORIES

Illustrations of Typical Scales (full size)

WM6

SUPPLIED WITH THE INSTRUMENT

Test lead set including shrouded crocodile clips

User Guide Part No. 6171-685

Test Record Card (5 supplied) Part No. 6172-111

AVAILABLE AS AN OPTIONAL EXTRA

A leather ‘test-and-carry’ case with a special
compartment for test leads Part No. 6420-088

Test Lead set red/black Part No. 6220-437

Test Record Card (Pack of Twenty)

Part No. 6111-216

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