70
Insulation resistance test. important make polarity
test the installation since visual inspection will only indicate conduc-
tor identification.
The insulation resistance readings for each test must not less than
1.
To final circuits
L N
Tester
(a)
FIGURE 14.
There are two tests carried out using insulation resistance tester
which must have test voltage 500 d.e. live and neutral conductors connected together) and the earthing
arrangements may made. these cases each circuit
should separately tested obtain reading greater than 2MΩ. Close all switches and circuit breakers.
4.3).
3.6)
The object this test verify that all fuses, circuit breakers and switches
are connected the line live conductor only, and that all socket outlets
are correctly wired and Edison screw-type lampholders have the centre
contact connected the live conductor. Test separately between the line conductor and earth, and between
the neutral conductor and earth, for every distribution circuit the
consumer’s unit shown Fig. The procedures are:
Phase and neutral conductors earth
1.0MΩ for satisfactory result (IEE Regulation 612.0MΩ (IEE Regulation 612.3.
3. These are line and neutral conductors earth and between line
conductors. Disconnect appliances.70(b) and record the result. 14. Remove all lamps. for 230 and 400 installa-
tions.
2.
2. Remove all lamps.2). Close all switches and circuit breakers.Basic Electrical Installation Work
356
should disconnected, since they will respectively glow, charge be
damaged the test.c.
4. Record the results a
schedule test results such that given Appendix the IEE
Regulations.
Where the circuit includes electronic equipment which might damaged
by the insulation resistance test, measurement between all live conduc-
tors (i. The insulation resistance these tests should
be not less than 1.
To final circuits
L N
Tester
(b)
.
Although insulation resistance reading 1. Disconnect appliances.70(a).
4 Testing polarity (612. 14.0MΩ complies with the
Regulations, the IEE Guidance Notes tell that much higher values than
this can expected and that reading less than 2MΩ might indicate a
latent but not yet visible fault the installation.
Between line conductors
1. Test between line and neutral conductors every distribution circuit
at the consumer’s unit shown Fig.3
