Megger MOM2, User Manual

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BD0333FE ZP-BD03E MOM2 23
5 OPERATING INSTRUCTIONS
SET / I min
position you select the minimum current to
be 50 A or 100 A.
Min current guarantee
(I > I min)
Max current
(I = I max)
Suitable for test objects ≤ 2 mΩ Recommended for test objects
> 2 mΩ
Capacitor only charged to
sufficient level to generate
selected minimum current for
set time
Saves instrument battery Capacitor is fully charged
Will push as much current as
possible through the test object
for set time. Current is deter-
mined as: I ≈ 2.5 V / [test object
R + 0.01 Ω] A
Allows for shorter time be-
tween tests Requires longer capacitor
recharge times
Note
If you get varying measurement results using
the I > I min position, change to I = I max .
Working at low temperatures
MOM2 can be operated down to -20°C provided that
the batteries keep a temperature over 0°C. When the
instrument is in use the batteries will generate heat
enough to keep themselves warm.
Kelvin Clamp/Probe practice
Important
To avoid adding unwanted transition
resistances to the measurement result the
Kelvin clamps or Kelvin probes shall be
connected directly to the test object and
not to e.g. a bolt head.
In some cases it might be advisable to use
separate sense cables, forming a conven-
tional four point measurement, in order
to get a more accurate voltage sense.
Save test results
A]
When LOG is activated measurement results
are automatically saved in the memory.
B]
When the log is OFF only the latest value is
stored and only until the performance of a
following measurement, which overwrites
the previous one.
Hold present test result
When the LOG function is activated the measurement
result is shown on the display for about 3 seconds.
After that it is stored in the memory. If you want to
study the result longer you can lock the display view
by doing as follows.
1]
Press shortly the trigger on the Kelvin probe
or the
TEST button just after a measurement.
The latest test result is locked and shown on
the display. This is confirmed by a padlock
symbol on the display and an audio signal.
2]
To unlock, press shortly the trigger on the
Kelvin probe or the
TEST button.
Delete present test result
1]
Press and hold, about 1 s, the trigger on the
Kelvin probe or the
TEST button just after a
measurement.
The latest test result is deleted from screen
and log. This is also confirmed by an audio
signal.
Note This is also possible to carry out when the
result is locked on display.
Recalling test results from the log
1]
Saved results can be recalled by scrolling to
desired label using the
▲ ▼
keys.
Delete results in the log
1]
Select label using the
▲ ▼ ◀ ▶
keys.
2]
By pressing the C key the display will prompt
" CLR " in big characters.
3]
Delete by pressing the OK key. Cancel can be
done by pressing the C key.
Note
In Circuit breaker testing mode the measure-
ment results will be deleted one at a time.
Delete all results in the log
1]
Press and hold, for 5 s, the red button below
the TEST button.
Note This will delete the log memory for both log
modes, Circuit breaker testing and Running
numbers.