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The DISPLAY button can be used to view the test results available after the
test.
This information depends on the measurement mode selected (see § 3.2.1).
If the measurement mode was either "Timed Run" or "Timed Run + DD", pressing
the GRAPH button displays the insulation measurement versus time curve (see §
3.3.2).
Press the TEMP button to correct the measurement result to the reference
5.2 STEP FUNCTION MODE
This function is based upon the principle that ideal insulation produces the same
resistance no matter what the test voltage applied.
Any negative variation of this resistance means that the insulation may be
defective. The resistance of defective insulation will decrease as the test voltage
increases.
This phenomenon is rarely observed with "low" test voltages, therefore at least
2500 V must be applied.
The usual test condition is a voltage increasing in 5 steps, each lasting for 1
minute minimum.
Assessment of the result:
A deviation of the resistance = f(test voltage) curve that exceeds 500 ppm/V
generally indicates the presence of mold or other deterioration.
A larger deviation or a sudden drop indicates the presence of localized
physical damage such as arcing or perforation of the insulation, etc.
Procedure:
In the SET-UP menu, select "Set Step Function 1, 2 or 3" by scrolling down to
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