Megger RCDT300 Series User manual

M
RCDT300 Series
Residual Current Device testers
USER MANUAL
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GSAFETY 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.
2
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.
NOTE
THE INSTRUMENT MUST ONLY BE USED BY SUITABLY TRAINED AND COMPETENT PERSONS.
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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:
GCaution: refer to accompanying notes
tEquipment protected throughout by Double
Insulation (Class II)
cEquipment complies with current EU directives.
Equipment complies with ‘C tick’ requirements
CONTENTS
3
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
N13117
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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 ■■
INTRODUCTION GENERAL DESCRIPTION
4
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:
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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
UNPACKING THE CARTON
5
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 ■■
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6
LCD DISPLAY FRONT PANEL
Loop test type
indicator (tripping or
non-tripping test)
Fuse
Blown
Warning –
refer to
User manual Battery
status
Measurement
ranges
Measured results
Phase
rotation
Test
Lock
Supply connection indicators
L-PE, L-N, N-PE
Test lead
connections
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)
Front panel cover
(folded under
instrument)
Backlight On/Off
(LT320 only)
RCD type selector:
AC
AC Selective
DC (RCDT320 only)
DC Selective -
(RCDT320 only)
Test
button
& Test
lead null
0º/180º
selector
LCD Display
Noise
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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).
Connection Panel
RCDT300 Series test lead connections
7
Mains plug test lead
connector
Single or 3Phase
connection
Neutral or 2nd
phase connection
Warning:
Refer to User
Guide
Maximum 300 V
connection across
terminals
Maximum 300 V
Phase to earth
allowed
)
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PREPARATIONS FOR USE (ALL INSTRUMENTS) GENERAL OPERATING INSTRUCTIONS
8
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.
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.
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Backlight operation (LT 320 only)
The RCDT320 LCD display may be backlit. The backlight function can be
selected at any time while the instrument is switched on by pressing the
BACKLIGHT Jbutton.
The backlight function will switch off automatically 15 seconds after the
instrument has finished testing.
Display warning symbols
GRefer to user manual.
Any time the warning triangle is displayed the operator should refer to
the user manual for further information.
LRange lock
Displayed at any time the [TEST] button is locked in the on position.
Battery condition indication. Refer to page 16.
fFuse blown indicator, appears when an instrument fuse has failed.
Refer to page 16.
>280V Displayed on the RCDT310 indicates a supply voltage in excess
of the allowed is present.
hot Indicates the instrument needs to cool down before it can continue
loop testing
Setup Procedure
Note: Line reversal and RCD touch voltage configuration features are
only available on the instruments as per the relevant tables in the
specification section of this document.
Reverse polarity detection / Touch voltage setting
To select Polarity reversal acceptance or rejection:
1. With the instrument switched OFF, hold down the [TEST] button and
turn the range knob to any ON position.
2. Keep the button held down until the instrument displays the ‘SET’
warning.
3. Now release the [TEST] button.
4. Press the [TEST] button again to view the current setting for
line/neutral swapping.
5. The display shows ‘L+L’ (instrument will perform tests with L & N
swapped) or ‘L+N’ (instrument will not perform tests with L & N
swapped).
6. Press the [LOCK] button or the PFC button to change the setting.
7. Press the [TEST] button to exit from the set-up menu.
RCD Touch voltage selection
To set the touch voltage inhibit limit:
1. With the instrument switched OFF, hold down the [TEST] button and
turn the range knob to any ON position.
2. Keep the button held down until the instrument displays the ‘SET’
warning.
3. Now release the [TEST] button.
4. Press the [TEST] button twice to view the current settings for the
touch voltage. 9
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10
Standard test probes and crocodile clips are supplied for connection to the
circuit under test.
Application
This instrument may be connected live to earth or between live
conductors of systems that have a rated voltage of 600 V a.c. rms to earth
and an installation (overvoltage) Category III or lower.
This means that the instrument may be connected to any fixed wiring of a
building installation, but not to primary supply circuits such as overhead
cables. To maintain user safety and ensure accurate measurements, only
use the test leads supplied by Megger Limited.
The display shows the fault voltage limit, ‘25 V’ or ‘50 V’.
If the fault-voltage display is active, a bar-graph display will also appear.
5. Press the [0º/180º] button to change the limit setting from 25V to 50V
and back.
6. Press the [TYPE] button to turn bar-graph display ON or OFF.
7. Press the [TEST] button to exit from the set-up menu.
Test leads
All test leads form part of the measuring circuit of the instrument and
must not be modified or changed in any way, or be used with any other
electrical instrument or appliance.
The power cord supplied with the Megger testers is a test lead that forms
part of the measuring circuit of the instrument. The overall length of this
lead must not be altered. If the power cord plug is not suitable for your
type of socket outlets, do not use an adapter. You may change the plug
once only by cutting the cord as close to the plug as possible and fitting a
suitable plug.
The colour code of the cord is:
Earth (Ground) Yellow/Green
Neutral Blue
Phase (Line) Brown
NOTE: A plug severed from the power cord must be destroyed, as a plug
with bare conductors is hazardous in a live socket outlet.
Test lead connection
The supplied test leads should be connected to the appropriate sockets
on the rear of the instrument marked L0 and L1, or to the 3 way test
socket.
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