3 Phase testing.

[Jay Sparks]

Can any one give me advice on 3 phase testing for my 2391 in Jan. Ive got all the books and have been doing domestic testing for about a year now so should be ok with that side of it. But I dont do alot of 3 phase. I just bought the Christopher Kitcher book " A practical guide to inspection, testing & certification of electrical installations" and its a good read but I dont think it gives much info on 3 phase stuff. Could do with some straight forward practical advice on the subject. Dont want to be spending £600+ only to fail on the three phase side. Just so you know I use the megger 1552 tester.

Cheers in advance

Jay

 

[AlanWirral]

This might help a bit mate. The testing itself isn't too different it's just remembering to combine some results due to the extra phases

http://www.electriciansforums.net/i...tallations/17733-2391-sum-practical-help.html

 

[Jay Sparks]

Thanks for that mate. I have read through this thread a few times and Im just abit worried that it seems too basic. Ive heard that on some db the neutral bar is connected to the db caseing (earth) and this must be disconnected/connected before doing certain tests, or am I going to deep for the info I need for the 2391. Any little pointers on the practical side of it would be great, like any thing they dont tell you that I might help me on the test.
Cheers
Jay

 

[brucelee]

hi mate dont worry i had no experience of three phase and its not as bad as you think
just remain calm and test in a methodical manner try writing the tests out as they are in gn3 for a pir
whatever you do remember safe isolation and when you have locked off put key in pocket so only you can unlock it
didnt have to disconnect the neutral bar?
only disconnecting of neutrals was on the assessment 2 which is to carry out a ir o a single phase board and locate the faults ie shot circuit 0.00M and low reading ir eg 0.02M
had to disconnect the neutrals and CPCs to find the circuit which had the fault which was giving the low reading

and to carry out the continuity of ring final circuit which you have to anyway

 

[Jay Sparks]

Cheers for that. Am a bit worried. Can do all the tests with my eyes closed normally but when someone is watching me I get nervous and start second guessing myself. R1 + R2 test on a 3 phase circuit, which phase do you connect to the cpc at the board, or does it not matter? And if they have used the armour from swa, or trunking etc as a cpc, do you just do the long lead test R2? i.e connect one end of the lead to the armour/trunking at the db then test at the end of the circuit? Hopeing this wont come up in the exam but I would still like to know anyway.

Cheers again

Jay

 

[brucelee]

hi mate as for R1 + R2 on a three phase say socket ido L1 - cpc first which you link first and our tutor if we asked held the link on each why i performed the test?
dont know if yours will
the swa was on this circuit with the three phase socket it was the only three phase circuit
the only other circuit that had a metallic sheath was a MI cable to a fused spur