Megger RCDT300, RCDT320, RCDT310 User Manual

RCDT300 Series
Residual Current Device testers

USER MANUAL

M

G SAFETY WARNINGS

■ Safety Warnings and Precautions must be read and understood before the instrument is used. They must be observed during use.

■ Continuity of protective conductors and earthed equipotential bonding of new or modified installations must be verified before carrying out RCD

tests.

■ Do not leave the instrument connected to the mains supply when not in use.

■ Circuit connections and exposed metalwork of an installation or equipment under test must not be touched.

■ Ensure that hands remain behind guards of probes/clips when testing.

■ Do not move the rotary selector knob position while a test is in progress.

■ The instrument should not be used if any part of it is damaged.

■ Test leads, probes and crocodile clips must be in good order, clean and with no broken or cracked insulation.

■ The battery cover must be in place whilst conducting tests.

■ Voltage indicator LED’s cannot reveal a N-PE supply reversal.

NOTE

THE INSTRUMENT MUST ONLY BE USED BY SUITABLY TRAINED AND COMPETENT PERSONS.

Users of this equipment and/or their employers are reminded that Health and Safety Legislation requires them to carry out valid risk assessments of all
electrical work so as to identify potential sources of electrical danger and risk of electrical injury such as inadvertent short circuits.

Some national safety authorities recommend fused leads for voltage measurement on high energy systems. If RCD or Loop tests are made it may cause
the fuse to rupture, and so they must be used with caution on voltage testing.

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CONTENTS

Safety warnings: 2
Introduction 4
General description 4

Un–packing the carton 5
LCD Display 6
Top panel 6
Lid open/closure 17

Preparations for use 8

Batteries 8
Preliminary test lead check 8
General operating instructions 8
Display warning symbols 9
Setup procedure 9
Reverse polarity detection 9
Touch voltage 10
Test Leads 10
Test lead connection. 10
LED indicators 11

Residual Current Device [RCD] testing 11

RCD type selection 12
∆I RCD Non-tripping measurement 12
1xI & 5xI RCD trip time measurement 12
0 or 180° testing 12
RampTest 12

DC Sensitive RCD test [RCD] 13
Voltage measurement 13
Frequency Hz (RCDT320 only) 14
Replacing batteries and fuses 14

Low battery warning symbol 14

To replace batteries 14

Fuse Blown indication 15

Preventive maintenance 15
Touch voltage enable/inhibit and Reverse polarity or
line/neutral swapping 16
General Specification 17
Basic and service errors 18
Accessories and equipment 18
Repair and Warranty 19

Symbols used on the instrument are:

G Caution: refer to accompanying notes
t Equipment protected throughout by Double

Insulation (Class II)

c Equipment complies with current EU directives.

N13117

Equipment complies with ‘C tick’ requirements

3

INTRODUCTION GENERAL DESCRIPTION

Thank you for purchasing the Megger RCD Tester.

For your own safety and to get the maximum benefit from your
instrument, please ensure that you read and understand the following
safety warnings and instructions before attempting to use the
instruments.

This user manual describes the operation and functions of the following
RCDT300 series of RCD testers:

RCDT310

RCDT320

The RCDT300 Series test instruments have
the following features:

Feature RCDT310 RCDT320

3 Phase safe ■■
Display backlight ■
Battery status indication ■■
Auto power down ■■
Fuse blown indication ■■
L-N-E polarity indicators ■■
Voltmeter ■■
Frequency measurement ■
Reverse polarity operation (can be disabled) ■■
∆I, I, 5I RCD trip time test ■■
Auto sequence test ■■
Fault voltage display (selectable) ■■
Max touch voltage selectable (25/50 V) ■■
Touch voltage display ■■
RCD trip current test (RAMP ■
0º/180º polarity selection ■■
Selective breakers ■■

4

UNPACKING THE CARTON

Feature RCDT310 RCDT320

DC breakers (1/2 I, I, 5I) ■■
30, 100, 300, 500 mA RCDs ■■
10mA/1000mA RCD ■
Plug ended test lead ■■
2 wire test lead probe/croc clip ended ■
Calibration Certificate ■■
IEC61010-1 300V CATIII ■■
EN61557 ■■

Unpack the carton contents carefully. There are important documents
that you should keep for future reference.

Please complete the pre-paid warranty card and return it to Megger
Limited as soon as possible to help us reduce any delays in supporting
you should the need arise.

Carton contents RCDT310 and RCDT320:

1 x RCDT300 series RCD tester

1 x 3 wire test lead with prods with clips

8 x AA (LR6) batteries (fitted in instrument)

1 x Test lead case

1 x Warranty card

1 x Calibration certificate

1 x Owners CD manual

1 x Safety instructions

5

LCD DISPLAY

FRONT PANEL

Loop test type
indicator (tripping or
non-tripping test)

Test
Lock

Phase
rotation

Fuse
Blown

Warning –
refer to
User manual

Measured results

Noise

Battery
status

Measurement
ranges

Supply connection indicators
L-PE, L-N, N-PE

LCD Display

0º/180º
selector

Test
button
& Test
lead null

RCD type selector:
AC
AC Selective
DC (RCDT320 only)
DC Selective ­(RCDT320 only)

Backlight On/Off
(LT320 only)

Test lead
connections

Front panel cover
(folded under
instrument)

RCD range
select:
10mA (RCDT320 only)
30mA
100mA
300mA
500mA
1000mA (RCDT320 only)

Neck strap
slots

Test selector:
∆ x I RCD trip time

1 x I RCD trip time
5 x I RCD trip time
AUTO (RCDT320 only)
Ramp (RCDT320 only)
V - AC/DC volts RMS
Hz – Frequency

(RCDT320 only)

6

Connection Panel
RCDT300 Series test lead connections

Mains plug test lead
connector

Single or 3Phase
connection

Neutral or 2nd
phase connection

Lid open/closure

1. Open lid by lifting up front panel tab (1).

2. Fold-away underneath instrument (2 & 3) and push into retaining slot
(4).

Maximum 300 V
Phase to earth
allowed

Maximum 300 V
connection across
terminals

Warning:
Refer to User
Guide

7

PREPARATIONS FOR USE (ALL INSTRUMENTS) GENERAL OPERATING INSTRUCTIONS

Batteries

The Megger RCDT300 series instruments are supplied with batteries
fitted. When batteries become exhausted, refer to section 8, battery
replacement.

Warning: Do not switch the instrument on with the battery cover
removed.

Preliminary test lead check

Functional verification

Before each use of the instrument, visually inspect the test leads, prods
and crocodile clips to confirm that their condition is good, with no
damaged or broken insulation.

Test inhibit

The following condition may cause the instrument to inhibit testing:

Out of range supply voltage

If an out of range voltage or frequency exists on the circuit under
test, or on a very noisy mains supply, testing will be automatically
inhibited.

Overheating

Repetitive RCD Ramp testing and some high current RCD trip testing
generates heat within the instrument. If this heat becomes excessive
the instrument will warn the operator and prevent further testing
until the instrument has had a chance to cool down.

Fuse Blown

A fuse blown will prevent the instrument from making further tests.
The fuse indicator will be displayed.

Default voltmeter

The default voltmeter automatically operates in all test modes, indicating
connection to a live system.

Auto Power-down

To extend battery life the instrument will automatically switch off six
minutes after the last operation.

It can be switched off manually by selecting [OFF] with the rotary
switch, or switched back on again by pressing the [TEST] button.

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