AM2 - My Experience

[brucey2343]

Hi, thanks again for the awesome post. I have a question though, when doing the global IR, you have to isolate the RCBO. Does this mean simply removing all cables and turning it off, or do you have to physically remove the RCBO from the board?

 

[SparkyChick]

On the boards in the test centre I went to, it was a Schneider or Merlin Gerin board that had isolators on the bus bar lugs, so for the global IR test, you disconnect the RCBO fly leads and slide the isolator to disconnect the device from the busbar.

I think it's an Isobar board, or something like that.

 

[telectrix]

SC's posts are extremely informative and I admire her for posting. that lot would have taken me 6 months just to type it.

 

[Pete999]

On the boards in the test centre I went to, it was a Schneider or Merlin Gerin board that had isolators on the bus bar lugs, so for the global IR test, you disconnect the RCBO fly leads and slide the isolator to disconnect the device from the busbar.

I think it's an Isobar board, or something like that.

A daft question SC, forgive me but if you operate that slide, do you not dis the circuit as well? or have I missed the point?

 

[SparkyChick]

RCBOs can be damaged by IR testing, so when you're doing the global IR test (to save much time), you isolate the RCBO from the rest of the installation. In a domestic board you'd technically have to remove the device from the board and disconnect it's fly leads, but in the Isobar boards, you isolate the device and disconnect the fly leads. Then, reconnect it, disconnect the load and test the RFC on it's own.

 

[Pete999]

RCBOs can be damaged by IR testing, so when you're doing the global IR test (to save much time), you isolate the RCBO from the rest of the installation. In a domestic board you'd technically have to remove the device from the board and disconnect it's fly leads, but in the Isobar boards, you isolate the device and disconnect the fly leads. Then, reconnect it, disconnect the load and test the RFC on it's own.

Ah OK thanks SC thought as much, your post was succinct, but not clear on that point, for the uninitiated I mean, thanks for the reply anyhow.

 

[LMT]

On my Pre AM2, the lad advised me to test IR individually. You can do global of course, but I felt more comfortable with the former after he went through it.

So if I wanted to do the dead tests on the ring final circuit,(RCBO) I would do the following...

Continuity of Ring final Conductors
- Disconnect the cables from the RCBO and earths for the circuit
- End to end test(Step 1)
- Cross connect opposite L-N and test at each socket(Step 2)r1+rn/4
- Cross connect opposite L-E, test at each socket and record highest reading(Step3) r1+r2/4 = R1+R2

Insulation Resistance
Right this is what I did for every single phase circuit, after doing R1+R2. I left live and neutral cables disconnected, but the earths for the ring CONNECTED. Disconnected the neutral and earth fly leads on the RCBO and did the IR test. That way I put that circuit to bed, moved onto the next circuit to test.

Just remember to always have your earth CONNECTED when doing IR.

 

[pennychew]

Great post this, I’m going to finish my level 3, nvq then the am2 and will be using this for my guide when it comes around.

The Am2 looks a lot more in depth than I thought it would be..

 

[kris jones]

just to throw in my 2 pence worth, I took on board everything that @SparkyChick sent to me (which I believe is freely available on here and nothing special for me personally) and I found it very useful.
I did it about a month ago now so anyone who wants recent experience feel free to contact me.

Id say its actually a very easy exam to do but also very easy to fail! You are given everything you need, there is no guess work or science required. Everything is written down for you but you have to be very cautious and read it carefully.

Honestly, if you can make off swa and sy/silflex cables using the correct glands and read the spec there is no reason not to pass the build. everything else should be second nature at this stage.

the test is straightforward as long as you know what your doing (if that makes sense)?

Fault finding was my biggest worry! Your given 7 faults which will only be: short circuit, open circuit, reversal or high resistance. The heating circuit is the worst as there is so many points possible to test.

DONT FORGET TO OPERATE SWITCHES ON THE SAFE ISOLATION!!!!!!!!!!!!

 

[Pete999]

just to throw in my 2 pence worth, I took on board everything that @SparkyChick sent to me (which I believe is freely available on here and nothing special for me personally) and I found it very useful.
I did it about a month ago now so anyone who wants recent experience feel free to contact me.

Id say its actually a very easy exam to do but also very easy to fail! You are given everything you need, there is no guess work or science required. Everything is written down for you but you have to be very cautious and read it carefully.

Honestly, if you can make off swa and sy/silflex cables using the correct glands and read the spec there is no reason not to pass the build. everything else should be second nature at this stage.

the test is straightforward as long as you know what your doing (if that makes sense)?

Fault finding was my biggest worry! Your given 7 faults which will only be: short circuit, open circuit, reversal or high resistance. The heating circuit is the worst as there is so many points possible to test.

DONT FORGET TO OPERATE SWITCHES ON THE SAFE ISOLATION!!!!!!!!!!!!

Hi Kris, firstly I have nil intention of sitting any of these courses, far too old, as well as being retired, but I was intrigued by your instructions in capitals at the end of your post, maybe I'm being a trifle thick, but what exactly are you getting at by that statement, not disputing it, just interested in what you mean, thanks.

 

[SparkyChick]

Hi Kris, firstly I have nil intention of sitting any of these courses, far too old, as well as being retired, but I was intrigued by your instructions in capitals at the end of your post, maybe I'm being a trifle thick, but what exactly are you getting at by that statement, not disputing it, just interested in what you mean, thanks.

I suspect he's talking about the light switches

You have to perform 3 cycles of safe isolation for different scenarios. The lighting circuit is in one of those scenarios and has 3 way switching, so has lots of strappers that could introduce potentials, so with the AVI connected you should operate the light switches in an order that systematically connects all the strappers, then move on to the next AVI connection setup.

 

[Pete999]

I suspect he's talking about the light switches

You have to perform 3 cycles of safe isolation for different scenarios. The lighting circuit is in one of those scenarios and has 3 way switching, so has lots of strappers that could introduce potentials, so with the AVI connected you should operate the light switches in an order that systematically connects all the strappers, then move on to the next AVI connection setup.

Thanks SC

 

[gazdkw82]

I still haven't sat this test yet (college messing me about) IV slowly just been making notes and building my knowledge up on the test.

A few questions.

What do you mean when you say don't cross the bonding and SY on the tray? Are they both already installed on the the tray or is it up to the installer under test to install these cables taking care not to cross them at any point?

Can you test as you install? Sometimes I find this useful as I go along?

When performing the testing of circuits do you suggest testing a circuit at a time going through the schedule or go the the schedule a circuit at a time?

Was you only expected to test the load side during safe isolation? We tested both supply and load side (20 tests)

 

[gazdkw82]

Also, was you expected to test the RCD at both 1x and 5x?

 

[kris jones]

I still haven't sat this test yet (college messing me about) IV slowly just been making notes and building my knowledge up on the test.

A few questions.

What do you mean when you say don't cross the bonding and SY on the tray? Are they both already installed on the the tray or is it up to the installer under test to install these cables taking care not to cross them at any point?

Can you test as you install? Sometimes I find this useful as I go along?

When performing the testing of circuits do you suggest testing a circuit at a time going through the schedule or go the the schedule a circuit at a time?

Was you only expected to test the load side during safe isolation? We tested both supply and load side (20 tests)

1. its not good practise to over lap cables, just looks like a birds nest, sure you dont anyway.
2. No testing takes place after the install and is a separate part of the exam with its own time limit.
You must follow the taught testing process of dead then live testing (cripper) and are watched doing it throughout. So you do do continuity of bonding of both gas and water (r2) then do cpc (r1/r2) of say your first circuit, then do next circuit but of this is a ring then do the ring procedure and then next circuits r1/r2 etc until all cpcs are covered. then do insulation res of whole board as its far easier than doing a circuit at a time and as youve installed it then there should be no faults. polarity is proven by now.
youll have to ask to move onto live tests as they have to liven up the board for you....just follow the cripper and practise testing until you are comfortable.

3. you'll test both single and three phase in the am2 numerous times. 10 sets for 3 phase and 3 for single.

As in my post above the one thing I almost got stuck on was having the switches changed over. The examiner will do it for you if you ask but not if you dont!

Good luck