AM2 Fault Finding..

[j-roc]

I recently had my AM2 exam. I passed everything apart from the fault finding section which was quite ironic because I thought I'd fluffed up the build and the inspection & test and felt more confident with how the fault finding went.

However, I have my retake coming up and the faults that I didnt get correct before were 2 for the heating system and I couldn't find a fault on the ring main although I was sure I followed the correct procedure.

Could anybody describe the steps that they would take to locate faults on these circuits?

Thanks

 

[m4tty]

Have you got a copy of gn3 mate?

 

[Zeespark]

GN3, and just follow what it says in there, its more likely to be a fault found during dead testing as opposed to live.

AndyGuinness

 

[j-roc]

I haven't got the guidance note 3 although it might be a stroke too late now as my exam is tomorrow morning headbang but I'll browse the pdf online.

Cheers for the help guys!

 

[kerching]

just because there is continuity 'from end to end on a ring' does not necessarily mean that it is a ring...if you see what I am getting at without giving the answer.

think of an 8 instead of a 0

 

[karlb]

I'm pretty sure we had a copy of gn3 in our am2. Also read the fault description as you should be able to determine what fault it is before any testing. I think mine said that the tester was unusable to perform a R1+R2 on the ring so you can tell its an open circuit before you even start all you have to do is find what conductor is open circuit

 

[Revved Up Sparky]

...I couldn't find a fault on the ring main although I was sure I followed the correct procedure. Could anybody describe the steps that they would take to locate faults on these circuits? Thanks

The easiest procedure to follow with any fault is to split the circuit into sections and systematically test each section until you pinpoint the fault. On a ring main you need to split the ring at the DB and again at approximately midpoint in the ring, then test each of the two sections before splitting each leg again and again, testing each length of cable between accessories until you find the fault.

 

[steptoe]

how did you go with your test?

 

[Mmmbluenose]

The best way to approach the faults is to know they can all fall into one of the following: short circuit, open circuit, crossed polarity or high resistance. The fault description should give you some indication of what sort of fault you are looking for.

I passed the fault finding a couple of days ago and all faults were found with the continuity tester. The heating faults are by far the hardest to find, be sure to have the wiring diagram and flow chart to follow through.

Out of the 7 faults to pass you need to have 5 you are certain on to pass. I also had two heating faults which I left till last as they takes a while to follow through.

 

[Revved Up Sparky]

I also had two heating faults which I left till last as they takes a while to follow through.

What sort of systems were the heating faults on ?.... S plan ... ? Y plan ?.... or just a single channel clock, stat and combi etc..... ?

 

[Mmmbluenose]

It's on a s plan heating system

 

[karlb]

You only need to do continuity. The description will tell you where the fault is alm you need to do is find out if the conductors go where they should go or of they are open circuit