AM2 - anyone recently done it?

[pitkin2020]

Just an update, so today went in a first thin was to sort this overload out. There was a data sheet on the wall which i only glanced at yesterday, it listed the pf, efficency and the rated current for the motor at each voltage. The 0.37kw came out at a current rating of the motor as 1.1, which they listed the equation they used as wattage/(1.73 x v x pf x ef) which IIRC was 370 / (1.73 400 x 0.77 x 0.66 (66%) came out at 1.1 anyway which is what i set the overload at. The overload could be set at 0.8, 0.9,1, 1.1 and 1.2 so was pretty happy with 1.1 as the setting.

Once the practical was finished i had to dead test and complete the test sheet before doing live tests and functional testing, testing didn't go to bad until the ring where they want you to calculate and show r1+r2 /4 and r1+rn / 4, and i just went blank trying to explain it lol. Anyway all tests carried out and functional testing everything worked as it should even the heating which was a bonus.

Finished the day off with safe isolation in prep for fault finding tomorrow, consisted of isolating a single circuit (lighting), the motor circuit checking it before and after the DOL and isolating the board completely.

tomorrow will be fault finding followed by the hour long exam

 

[Richard Burns]

Sounds good so far.
I have graded the AM2 too low as I did not include efficiency in my calculation at all and even tried to remove power factor, but they were included, sorry about that but I think it sounds much better what you have done with the overload, I am glad the information was there.

It is easy to go blank at times, the ring calculation itself is easy but explaining it is not so easy.
I tend to simplify it by saying you are measuring end to end (r1,rn,r2) and then when in use, at the middle of the ring, you have each leg as half the end to end length. You also have two legs in parallel.
Length is halved so resistance is halved, because there are two (equal in some ways) legs the resistance of two identical conductors in parallel is half the individual resistance, so overall you have half and half again, so one quarter of the sum of the end to end values.
All worked and so a good result.

Good luck with fault finding, be logical and remember what test equipment you have and so the fault must be discover able with that equipment.

Then only a simple exam, can't be hard surely!!

Good luck.

 

[pitkin2020]

cheers richard youve been a great help

Thats what i tried to say with regards to the ring circuit but it sounded nothing like that lol. It was the same when i said about PFC, i said when your doing the Ze test the megger all shows it at the same time doesnt it?? I meant more that the megger shows two readings not that PFC is found when doing Ze, again knew what i meant just worded it badly lol

Hopefully fault finding wont be a major drama, can only be cable faults as they have said no faulty equipment so im expecting high resistance, reverse polarity, etc etc

 

[pitkin2020]

Well after all that I failed......so annoyed as I have failed on something so simple. I phoned the assessment centre this morning and they said it was because when testing the light I didn't test between N and E. Pretty sure I did but assessor is adamant I didn't. No point complaining rebooked to sit the 1/2 assessment again next Friday for the sum of £107.
My mark sheet below
https://goo.gl/photos/GLJ6PtW4egZHBUCc8

 

[Richard Burns]

Sorry to hear that you were denied passing.
To look on it positively you know that everything you did was good and it is not hard to train up on safe isolation!! Especially when you know it anyway.

It is possible to easily miss something and this is what the AM2 is all about, ensuring that you have the skills to catch your misses, whilst hoping that the misses are limited.

Irritating, but easily fixed and you can go in in a confident frame of mind on Friday ready to pass.
I am sure you will fly through and in later years this brief hiatus will not matter at all.

 

[pitkin2020]

Yeah as annoying as it is no point dwelling on it, I k ow the mistake and how to rectify it.
Tbh I though i had failed because I checked at the switch rather than the light as I knew the switch was the first point and had a permanent live and neutral there. I think I will do it at the light next time anyway and make sure once I've done the 3 tests I will switch one of the switches and do the 3 tests again

 

[gazdkw82]

Wouldn't testing at the switch be more accurate as it's most likely the furthest point in the circuit

 

[pitkin2020]

Wouldn't testing at the switch be more accurate as it's most likely the furthest point in the circuit

In the am2 the switch is the closest point to the DB.

I've actually passed this now and 2nd time around tested at the lumiaire. I asked about testing at the switch and they said that's perfectly acceptable also.

 

[Richard Burns]

I am glad you have passed, well done.
I think it was almost guaranteed this time and this was proved right.
Onward and upward.

 

[pitkin2020]

Yeah thanks Richard, should have been a pass the first time lol but one simple step (which I bloody well knew too) missed resulted in a fail.
Just need to finish my NVQ now which is 95% there and I'll be qualified

 

[gazdkw82]

Yeah thanks Richard, should have been a pass the first time lol but one simple step (which I bloody well knew too) missed resulted in a fail.
Just need to finish my NVQ now which is 95% there and I'll be qualified

whats left to do?

 

[pitkin2020]

whats left to do?

For me just a little bit of my NVQ, mainly the green energy section