Megger INGVAR, User Manual

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BH0654BE ZP-BH05E 41
7 HOW TO USE INGVAR
7.13 Reading maximum
current at an operation
The highest current value showed on the display at an
operation is stored.
1]
Press
ESC
repeatedly until a current value
and the text "max" appears.
The maximum current value is updated every
1/3 second.
7.14 Measuring operating
limits
There are three ways to measure operating limits:
▪
Normal generation. Used when there is little risk for
undesirable heating in the object under test.
▪
Manually-controlled momentary injection.
▪
Limited-time generation. Used when you do not want to
expose the object under test to needless heating.
Method 1: Normal injection –
gradually increase in current.
In this method current is sent out continuously. The
current is gradually increased until the object being
tested operates. When this happens:
a) the
LATCH lamp lights up
b) the current value is frozen on the display
c) the current to the object is interrupted
When you are testing protective relay equipment you
can, as a next step, reduce the current and freeze the
displayed value to obtain information about the drop-
out function.
1]
Basic settings:
OPERATE OFF.
CURRENT ADJUST Lower than the tripping/operating
limit.
HOLD function ON.
AUTO OFF STOP INPUT.
2]
• For protective relay equipment:
Set the stop condition to (for example):
• For breakers:
Set the stop condition to INT .
3]
Press
TIME
to start generation.
4]
Increase the current until operation occurs.
The value frozen when operation occurred is
now presented on the display.
Note If the impedance of the object under test
changes during operation, you should use the
maximum current value during the operation
as pick-up value. Press the
ESC
button to get
the maximum value.
The following steps apply only when testing protective
relay equipment:
5]
In order to measure the drop-out function,
change the stop condition to (for example):