Am2 exam failed on LIVE testing any guidance or help?

[RyanF]

Hi All,

Ive just got my results through and I failed my first attempt of AM2 exam on the live testing of inspection and testing. I passed everything else just the live testing simply all because I ran out of time that was allowed for the inspection and testing. So Im gonna try and get re booked back in asap.

So live testing let me get this right ( if i am wrong the let me know)

So first stage of live testing is:-

Polarity live:- test between L1- L2 etcc L1-N... L2- E ensure getting 400/230V.

Ze with board FULLY isolated, with permission disconnect the main earthing conductor and test between E to L1, E to L2 and E to L3. Record on test sheet the highest value as Ze. Must comply with tncs earthing arrangement and maximum value permitted. Once test is done reconnect main earth back in.

I can then take this value and work out zs for each circuit.

Zs exactly the same as the Ze test but, earthing conductor is connected. As I want all parrallel paths in circuit for this test. Record on test sheet.

Then onto PFC test first test PEFC

Test between L1- E etc note the highest reading.

PSCC test L1- N etc note the highest reading.

Double highest value on test sheet as PFC.

Rcd testing,

Simply plus in test meter at further point of the ring and test auto 30mA at 1/2, 1 and 5 times. Compare tripping times to bs7671. Record times on test sheet.

Then simply test functional of test switch to ensure rcbo opperates.

Then phase rotation

Simple 3 probe test on incoming side of the isolato to check that the phases are correct and no phases at mixed.

Then functional test on all corcuits and that they operate as they should etc.

Any hints/ links or guidance will be much appreciated!

 

[Richard Burns]

RCD test at closest socket to board or at RCD terminals.
Phases should be l1 l2 l3 at supply. Phase rotation should also be consistent along a 3 phase circuit: test supply, at intermediate points and end during dead tests.
The rest is ok, when you test zs this should be the same test method as to obtain pefc
Good luck with the exam.

 

[davesparks]

Ideally you would test the PSCC between phases rather than doubling the PEFC, however you must check that the test meter is capable of this as not all of them are.

 

[Ian1981]

I don’t think the colleges will let them do a PSCC test between phases.

 

[PEG]

Hi,did you prove,and re-prove,your test equipment?

 

[davesparks]

I don’t think the colleges will let them do a PSCC test between phases.

Why not? They are trainee electricians on the verge of completeing their training so should be more than capable of taking such measurements.
If they are not competent to carry such simple measurements then they are not yet ready to qualify as electricians.

In my opinion, if you are not capable of carrying out such a simple measurement on a three phase supply then you are not yet ready to be an electrician.

 

[Baker1988]

Hi Ian is correct on the AM2 the college wont let you test between phases and you need to just use the rule of thumb and double it.

I dont think it is a fact that they are not capable of doing the test as when i did my AM2 i was more than capable but the college just dont want you to do it, i agree you should as its a simple test but if they dont want us to then we cant do it simple as that really.

 

[Ian1981]

With all live testing there lies a certain risk which as competent persons is diminished a little, the students may not be as competent at this stage and I guess the college aren’t prepared to let the students take that risk and to cover their backsides if a student injures themselves.