Megohmmeter Models 5000N/5100/5110
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RATIO TESTING
In time resistance reading (dielectric absorption ratio), readings are taken
at 30 seconds and 60 seconds to obtain the dielectric absorption ratio.
Insulation resistance @ 60s
Insulation resistance @ 30s
This test is useful for increasing the accuracy of spot testing. In general,
a ratio of 1.25 to 2 or better should be required. (Below 1.1 is dangerous;
1.1 to 1.25 is questionable; 1.25 to 1.4 is fair; and 1.4 to 2 and above is
good.) A ratio below this indicates that repair is probably needed.
Remember that a DC insulation test may be used for acceptance testing,
but is more commonly used to check the gradual deterioration of
equipment over its lifetime. Consult your equipment manufacturer for
specific test or test voltage if not known.
Insulation resistance decreases with moisture, temperature and age, and
should be recorded over time at a given temperature and corrected.
= Dielectric Absorption Ratio (DAR)
Summary of Contents for 5000N
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