Operation; Warning; The Detachable Lid; Performing A Test - Megger BT51 Guia Del Usuario

WARNING

Ensure that the equipment or conductor to be tested is de-energised before
connecting the instrument.

THE DETACHABLE LID

The lid hinges are fitted with spring loaded clips and are designed in this
way for two reasons. Firstly, if the lid is accidentally thrown open to its full
extent the hinges will not be strained or broken but the lid will be safely
unclipped. Secondly, the lid can purposely be removed if required when
the instrument is in use by simply opening it up to its full extent and gently
pressing down on the opening edge while holding the tester body firm.
The hinges will then unclip. To replace the lid, hold it vertically and push the
hinges back into their clips again while restraining the instrument. Then fold
the lid shut.

PERFORMING A TEST

(assuming duplex handspikes are used)
1. Connect the test leads to the instrument terminals
current leads to C1 and C2, potential leads to P1 and
P2. Note:- Duplex handspikes provided by Megger
Limited are identified as follows: The current lead is
black and the spade connector is stamped with a 'C',
the potential lead is red and the spade connector
is stamped with a 'P'. On the handspikes themselves, the
potential spike is marked with a 'P'.
2. Turn the range selector switch to the appropriate
position.
3. If it is desired check that the instrument is
functioning correctly by touching the two handspikes
onto a known low resistance piece of metal with the
potential spikes as close as possible to each other.
A zero reading should be obtained on the digital L.E.D. display.
Note:- Current will only pass when the circuit is completed between the
C1 and C2 spikes. The green L.E.D. light will illuminate to indicate when
this occurs. Make sure also that the low battery warning light does not
illuminate.
4. Press the handspike sets down on to the equipment
or conductor to be tested. (The handspikes may be as
far apart as the lead length will allow).
5. Read the resistance measured from the digital display
6. If the over-range symbol appears on the display when
the 20 mW range is in use i.e. a 'I' as the left
hand digit with the remaining L. E. D's blank, turn the
selector switch to the 2000 mW range and repeat the
test. If the over-range symbol (i.e a 'I' as the left hand
digit) appears again the resistance being measured is
outside the range of the instrument.

Operation

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