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Listed Below are a few of the basic test, sequences and description of the purpose for them also equipment used some may require more some will require less  

1. External earth fault loop impedance

Purpose: Too ensure the installation has a good earth enabling further test to be carried out.
Standard Test Equipment: Earth loop impedance tester/ Earth-fault loop tester

2. Continuity of protective and bonding conductors

Purpose: Checks that circuit protective conductors (normally green and yellow cables) are present at every electrical accessory on the circuit and are continuous Also that the main bonding conductors and main earthing conductor are continuous and correctly connected
Standard Test Equipment: Low reading DC Ohmmeter or an insulation resistance test meter

3. Continuity of ring final circuit conductors

Purpose: This ensures that all ring final circuits within an installation (these are usually sockets in a standard domestic installation) have no breaks within it no interconnects or bridged and is a continuous ring
Standard Test Equipment: Low reading DC Ohmmeter capable of passing a minimum test current of 200 mA

4. Insulation Resistance

Purpose: This test is to ensure that there are no short circuits between live conductors or between live conductors and earth, and that there is no deterioration in insulation resistance caused by damage or dampness if the insulation around a cable is still intact and has not broken down over time. It is a good indicator of the age of an installation.
Standard Test Equipment: An insulation resistance tester

5. Polarity

Purpose: Check Polarity at the main supply point is correct.
The phase conductor is connected to fuses, single pole circuit breakers and switches.
Incoming supply is connected to back contact of screw in type fuses.
The phase conductor is connected to the centre contact of ES type lampholders.
All wiring is correctly connected at socket outlets and other similar accessories
Standard Test Equipment: Ohmmeter

6. Earth electrode resistance

Purpose: To make sure that any earth electrode used is of a sufficiently low impedance to allow the timely operation of the RCD protecting the installation.
Standard Test Equipment: Earth-fault loop tester

The following tests are carried out with the SUPPLY SWITCHED ON

7. Earth fault loop impedance

: Purpose to ensure impedance of the earth path is not too high even at the furthest point so that sufficient current will flow under fault conditions to bring out the circuit breaker protecting the circuit.
Standard Test Equipment: Earth-fault loop tester

8. RCD test

Purpose :  RCD (Residual current device) should comply with BS 4293 that means they are provided with a built-in self test system ('go, no-go') which is intended to be operated regularly by the user additionally test there are other that also have to be carried out, (the 'go, no-go' tester alone is no longer adequate.) These measure the time taken for the device to operate in accordance with regulations
Standard Test Equipment: RCD Tester

9. Functional testing

Purpose: Switching on off switches, isolators, MCB's etc. work as they should.
Standard Test Equipment: Self explanatory

Testing can be hazardous, both to the tester and to others who are within the area of the installation during the test. The danger is compounded if tests are not carried out in the correct sequence. Any test which fails to produce an acceptable result must be repeated after remedial action has been taken. Any other tests, whose results may have been influenced by the fault concerned, must also be repeated.
RCD residual current device
RCCD residual current operated circuit breaker
SRCD socket outlet incorporating an RCD
PRCD portable RCD, usually an RCD incorporated into a plug
RCBO an RCCD which includes overcurrent protection
SRCBO a socket outlet incorporating an RCBO