● Initial Tests: Conduct insulation and earthing tests on wiring sections before completing the entire system.

● Final Tests: Perform additional tests upon system completion as part of the commissioning process.

● Manufacturer Specifications: For addressable systems, measure impedance if specified by the manufacturer.

● Compliance: Ensure inspection, testing, and certification of wiring meet BS 7671 requirements before commissioning. (see Clause 39).

The following recommendations are applicable.

All cables should be tested at 500 V d.c. with insulation resistance at least 2 MΩ. Disconnect cables from equipment before testing.

Test earth continuity and, for mains circuits, earth fault loop impedance per BS 7671.

c) Circuit Resistance: Measure resistance of circuits if specified by the manufacturer and perform any additional tests required.

d) Polarity Check: Verify correct circuit polarity where necessary.

e) Documentation: Record and provide test results to the commissioning organization.

38 Inspection and testing of wiring