MEASUREMENTS
4.2 Insulation Resistance
Measurement principle
500 V d.c.
Fig. 08: Insulation resistance measurement principle
Practical measurement
Warnings!
• Make sure tested object to be disconnected from mains voltage!
• Do not apply any external voltage to test terminals, make sure object
to be tested is de-energised!
• Switch "on" main switch of tested object as well as other switches,
in order to include all electronic parts of tested object in the test!
• Do not touch any part of tested object during the test!
• Discharge tested object after test end (capacitors may store
dangerous voltages)!
Test procedure
STEP 1
Prepare the instrument
• Place it into such a position that both test points of tested object will be
reachable by the test leads (take into account the 2 m long test leads) or
use optional test lead extensions.
• Connect the instrument to mains voltage via mains cord.
• Connect test leads to test terminals of the instrument.
• Select Rins function setting function rotary switch to Rins position.
• Switch on the instrument, initial display state is present (- - -).
∼
Ω
5 M
A
V
Rint.
short all
live parts
_
∼
+
∼
12
Ri
L1
L2
L3
N
PE
PE collector