Safe isolation at AM2

[fretfingers123]

I have my AM2 exam tomorrow and I have a query about where to actually isolate and lock off. On my training day I was shown to lock off the main switch in the board then perform the test sequences with the voltage indicators, put key in pocket after fitting warning notices etc etc. but today I spoke to someone who do their am2 a couple of years ago and said I should isolate and lock off the main isolator external to the board, and put the signs there. On the basis that if you only lock off at the board, then the very bottom of it still has live incomers in it. Where should I lock off?!? AM2 tomorrow any help is much appreciated. Cheers

 

[Richard Burns]

If your board is intended to replicate real life then unless the installation you are testing has a main isolator switch then the closest you can get to complete isolation if at the main switch in the board.

If the isolator external to the board is only for connecting the board to a power supply then this would not be an actual part of your installation so you would not be able to isolate there.

I do not know the detailed requirements of the AM2 exam but I would suggest that the isolation at the board's main switch , as you have been trained, would be acceptable and expected.

 

[fretfingers123]

Hopefully it will become a bit more apparent when I get in there! Thanks for your help!

 

[telectrix]

agreed. then with the main switch in the DB off, remove cover aand use the incoming side of the isolator/switch to prove your tester.

 

[Paul.M]

"Safe isolation" = The safe isolation of the circuit or circuits that you are working upon.

If your working on the upstairs lighting circuit, lock off the MCB for that circuit only.

If your working on the C/U or DB, lock off the main isolation switch, therefore no danger of being shocked on anything that you are working on in both cases.

 

[Adam_glover18]

Where I'd did mine you switched a rotary isolator off and locked it off that was on a wall away from the board put the key in your pocket and then take db cover off tested the test lamps on proving unit,the test for dead and then re test your test lamps and away you go. But if you fail this section it's a instant fail I hope this helps.

 

[fretfingers123]

Brilliant, thanks for all the advice, im only just becoming aware that in lot of peoples scenario at their AM2, their board was fed from an isolator elsewhere. Reckoning this will be the point of isolation and lock off.

 

[Pete999]

Hi
Same as Paul.M, if you are working on the DB/CU then isolate at main switch feeding that board, it it's a circuit from the DB/CU then nothing wrong with isolating at the CB.