3M Dynatel 945DSP, Инструкция по эксплуатации

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Insulation Soak
Selects R-G or T-G
Saves the reference reading
This function monitors the leakage resistance from the test
leads to ground and indicates changes in the insulation
resistance while it is stressed with a high voltage over time.
The test begins by displaying the insulation resistance of
the Red lead in the upper left box. This box has a thicker
border than the others indicating that this reading is ‘live’
and will change as the insulation resistance on the lead
changes. After the initial reading has become stable, the
945DSP stores it in the right hand box. Now observe the
reading as it changes over time. Pressing moves the
‘live’ reading to the lower box showing the insulation
resistance of the black lead. The key is used to update
the initial reading.
The way the insulation resistance changes over time gives
you an indication of the nature of the problem. Wet cable
faults tend to dry out when tested. The final value will be
higher than the initial saved value. Oxidation tends to
breakdown and become conductive over time which is
indicated by a reduction in resistance from the initial value.
Since you may want to run soak for some time, the
automatic shut off timer is extended to 30 minutes during
the soak test.
Note that voltage compensation is not used during the
insulation soak test. Foreign voltage on the pair will affect
the accuracy of the insulation soak measurement.
After completing the test, press to return to the
resistance screen or any other blue key to run another test.