Inspection And Testing

[ag95]

Hello, i am new to the website and am an Electrical Apprentice. I am currently learning inspection and testing. i was wondering if there was anyone who could explain, the whole testing process in general in case someone explaining it may help me understand it easier or could possibly guide me to a suitable website for it. Thanks very mauch

 

[Hefferl]

Also you could do worse than reading Chris Kircher's book "Practical Guide to Inspection, Testing and Certification of Electrical Installations"

http://www.amazon.co.uk/Practical-Inspection-Certification-Electrical-Installations/dp/0080969070/ref=sr_1_7?s=books&ie=UTF8&qid=1395579408&sr=1-7

 

[Doc Hudson]

The first key I believe is to note the order of the words: "Inspection And Testing". you will be inspecting an installation visually checking for all obvious safety criteria. Also establishing the layout of distribution boards final circuits, and their respective protective devices. It is essential to know the type and composition of circuits you are testing so that you understand what the acceptable test results should be. i.e. it is no good just plugging an earth loop impedance tester into an accessory taking a reading, without knowing first what your maximum permissible values can be and what the expected values should be proportional to installed cable lengths, in relation to the circuit in question. The objective is not to just get a list of numbers to put on a certificate or inspection report, it is to verify an installation is safe.

Doc H.

 

[codger]

Hi. I heard an interesting quote today....'The Inspection and Testing process should be 70%/30% respectively. I thought it was quite reasonable actually. Think a lot of people place great reliance on the testing and not the inspection. Your testing should back up, really, what you see on your inspection.

The reason for the tests are....

Continuity of cpc - To check there is and earth at every relevant point on the circuit (continuous).

Continuity of ring final circuit conductors - To ensure the sockets are on a ring

Insulation Resistance - To check the cable hasn't been damaged by some joiner on bonus, zapping a screw through a cable. Or that the insulation between the conductors within the cable sheath has not broken down and the conductors are touching.

Polarity - To ensure cables are connected into the correct terminals...Live in the live connections, neutrals in the neutral bar/terminal etc

Earth Fault Loop Impedance - To ensure that as much of any fault current flowing is able to flow through the circuit in order to operate the fuse/circuit breaker in the quickest possible time.

Prospective Fault Current - To ensure that the fault current at the point you are testing will not cause the nearest protective device to completely blow up.

RCD test - Checking that the RCD will operate in the required time during an increase in the current through the cpc of the circuit.

Hope this helps.

 

[pewter]

https://www.youtube.com/embed/EZBhiJq4TL4?feature=oembed