1. Testing of Low Voltage Installations
(Textbook Chapter 11)
Electrical Installation II

2. Procedure for Inspection, Testing and Certification
Divided into inspection and testing.
Inspection
Identification of conductors
Cable rating
Fire barriers
Isolation
etc.
Electrical Installation II

3. Testing of LV Installations
Sequence of Test
Continuity of protective conductors
Continuity of ring final circuit conductors
Insulation resistance
Polarity
Earth electrode resistance
Earth fault loop impedance
Functions of all protection device
Functions of other equipment
Electrical Installation II

4. Testing of LV Installations
In the event of any test indicating failure to comply, that test and those preceding, the results of which may have been influenced by the fault indicated, should be repeated after the fault has been rectified.
Electrical Installation II

5. Testing of LV Installations
Continuity of protective conductors
Every protective conductor, including all conductors and any extraneous conductive parts used for equipotential bonding should be tested for continuity.
At the mains, connect together the neutral and protective conductors, then check the continuity between the neutral and the earth at every socket outlet.
Electrical Installation II

6. Testing of LV Installations
Continuity of ring final circuit
Electrical Installation II

7. Testing of LV Installations
Insulation resistance
Fuse links and switches should be closed.
Lamps should be removed, if not practical, lighting switches should be switched off.
Electronics equipment should be isolated.
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8. Testing of LV Installations
Electrical Installation II

9. Testing of LV Installations
Electrical Installation II

10. Testing of LV Installations
Polarity
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11. Testing of LV Installations
Earth electrode resistance
Electrical Installation II

12. Testing of LV Installations
Electrical Installation II

13. Testing of LV Installations
Electrical Installation II

14. Testing of LV Installations
Earth fault loop impedance
Before the test, the bonding connection to electricity supplier’s earthing should be disconnected.
The value should not exceed the requirements of Code 11, Tables 11(8) to 11(14)
Electrical Installation II

15. Testing of LV Installations
Functional test of protective devices
RCD by RCD tester, e.g. within 0.3s at rated residual current
MCB and other protective devices by hand operation
Electrical Installation II