Amprobe MEGATEST-1000 Megohmmeter - Manual (Page 15)

5.2 “M Ω” POSITION
5.2.1 INSULATION RESISTANCE:
INSULATION RESISTANCE MEASUREMENT WITH TEST VOLTAGE OF 50V, 100V,
250V, 500V OR 1000V
o
ATTENTION:
Before making the insulation test make sure that the circuit
under test is not energised and all the relative loads are
disconnected.
Turn the switch on M Ω position.
The key FUNC permits to select one of the following measuring modes
(which can be shown cyclically when pressing the key):
FUNC
Mode “MAN” (maximum test time of 10 seconds or set by the pressing
duration on the GO key). Recommended test.
Mode “AUTO” (the test ends when the measured value gets stable). This
test can be effected in case the installation has some capacities which
are to be charged in order to evaluate the real insulation resistance.
Mode “TIMER” (test duration depending on the selected interval (from 10
to 999 seconds). This test can be effected in case a minimum measuring
time is required.
5.2.2 “MAN”, “AUTO”, “TIMER” MODES
Procedure to measure the insulation resistance valid for modes "MAN", "AUTO", "TIMER"
1. Select the desired mode by means of the FUNC key.
2. Connect the black and blue cables to the instrument input terminals P and N
respectively,
Example for the use of the instrument to check
insulation between phase and earth in an electrical
installation using untied cables.
Connection of the instrument terminals for M Ω test.
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