Eaton SEFELEC 1500M, Руководство пользователя

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SEFELEC1500M Instructions 152 V1.06
The contribution of the cable to the measured leakage current decreases exponentially
with time. It is, therefore, important to specify the time taken for the test in order for the re-
sult to be significant. SEFELEC1500M devices can satisfy this requirement thanks to the
built-in timer, able to time from
0.1 s to nearly 3 hours .
16.4.4. TEST VOLTAGE FOR MEASUREMENT
Insulation resistance measurements are used to check that materials or equipment meet
defined standards; it is important to refer to these standards when choosing the test volt-
age. Standard test voltages are usually:
50, 100, 250 and 500 DC volts. If there is no rec-
ommended test voltage, choose a voltage of 100 volts for the measurements.
Where measurements are made on capacitive devices and when the insulation resistance
is to be measured at different voltages, always start from the lowest test voltage and in-
crease the voltage for subsequent measurements. Reducing the test voltage may give in-
consistent results.