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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