15. Inspection and Testing Flashcards
How do you use your senses when inspecting an installation:
Hearing - Listening for any arcing
Sight - Any cracks or loose connections.
Touch - Can you feel any swarf or sharp edges?
Smell - Can you smell any burning?
Which tests must be carried out during inspection and testing:
- Continuity of protective conductors. (R1+R2)
- Insulation Resistance
- Polarity (Confirmed when doing R1+R2
- Prospective fault current testing.
- Functional testing (see if it works)
- Verification of automatic disconnection of supply (EFLI)
Which test instruments are used during inspection and testing
- Low resistance ohms meter.
- Insulation resistance tester
- Earth loop impedance tester
(Used to test prospective fault current) - RCD tester
- Approved voltage indicator.
- Earth electrode resistance tester
- Multifunction tester
Prospective fault current Test
- Test instruments used
- Purpose of the test
- Test method
Instrument: PFC or EFLI tester.
Purpose: To measure the maximum fault current that may occur within the installation and confirm that any protective devices have the breaking capacity to suit.
Method: Measurements are taken of the PEFC and PSCC and the highest is recorded.
What is PFC (prospective fault current)
The highest amount of current that will flow under fault conditions
What is PSCC
What is PEFC
PSCC:
(Prospective short circuit current)
The fault current if 2 of the live conductors are shorted.
This measurement is taken between live conductors.
PEFC:
(Prospective earth fault current)
The fault current if a line conductor is shorted to earth.
This measurement is taken between line conductor and earth
Why inspect installations?
- To verify they are safe to put into use.
- To verify they are safe and suitable for continued use.
- To verify that any alterations or additions do not impair the safety of the existing installation.
