2391 March Completed

[vernam616]

Came out of the March 2012 exam liteally 30 minutes ago, anyone done it? How did you find it?

 

[sonnyjim]

Just done the exam aswell i also done it in feb one not got my results for at one. I found this one alot easier.

 

[vernam616]

So you took the exam in feb and possiby passed and you took this one?, i didnt realise you could do that

Anyway how did you find the exam? I found it surprisingly easy

 

[wams]

I also did the exam. does any one have questions about certain questions in the paper. Questions that you may have had thought were difficult?

 

[bobbyhowler]

I also did the exam. does any one have questions about certain questions in the paper. Questions that you may have had thought were difficult?

Sequence of tests after the earth electrode rest?

 

[wams]

Sequence of tests after the earth electrode rest?

I got that 1 wrong now that ive looked at GN 3. The test following are:


Protection by automatic disconnection of supply
Earth Fault loop impedance
Additional Protection

 

[eleczar]

I just did the exam to! I think it was quite straight forward however im concerned i messed up the question about checking the carpark radial?

Does that just mean 'checks' ie cable condition, earthing, terminations etc and not any testing as it only stated CHECK.

Also I have never tested an RCBO and in a blind moment of panic i decided you should remove the earth tail from the rcbo ? THis was an idiotic thing to write but will i lose all marks for that question because i answered it pretty well apart from that stupid comment !!!

Apart from that im quite happy !!

How did others find it??

 

[vernam616]

Well for earth electrode question i wrote

Ze - external earth fault loop impedance
PFC - prospective fault current
Rcd test as its said state 3, and it could have been any id of thought


The rest was surprisingly easy, did everyone manage to get the last question correct by applying 80% rule of thumb to the max values?

I got "not acceptable" for the first three and "acceptable" for the last value

 

[wams]

I just did the exam to! I think it was quite straight forward however im concerned i messed up the question about checking the carpark radial?

Does that just mean 'checks' ie cable condition, earthing, terminations etc and not any testing as it only stated CHECK.

You may of had a different paper to me as as I had to write a sequence of test on the continuity of the car park lights that incorporated 2 core SWA.

I may have struggled?

 

[Adam W]

I did it as well. Trying not to think about it because there's a few questions I think I may have messed up.
I got 'not acceptable' for the first 3 results as well, although earlier in the question I said the tabulated figures can be compared to measured results either by multiplying the tabulated by 0.8, or multiplying the measured results by 1.2, which doesn't work.

What did everyone else put for the voltage to test surge protected sockets?
And the voltage to test between SELV and a 400v 3 phase motor?

 

[wams]

I applied the rule of thumb (0.8 factor) but I got unsatisfactory - satisfactory - unsatisfactory - satisfactory.

Can anyone remember the scenario

 

[wams]

i did it as well. Trying not to think about it because there's a few questions i think i may have messed up.
I got 'not acceptable' for the first 3 results as well, although earlier in the question i said the tabulated figures can be compared to measured results either by multiplying the tabulated by 0.8, or multiplying the measured results by 1.2, which doesn't work.

What did everyone else put for the voltage to test surge protected sockets?
And the voltage to test between selv and a 400v 3 phase motor?

500 v d.c

 

[Adam W]

An office wired 12 years ago, BS88 100A main fuse, wired in pvc singles in pvc conduit and trunking.
5 metal bollards in car park wired in 2 core SWA controlled by a time clock and contactor.
3 phase board next to the service head, TN-S earthing.
A new occupier had just moved in and an EICR needed to be carried out, tested at 20°c.

Can't remember much more than that.

 

[Adam W]

500 v d.c

For both?

 

[vernam616]

I wrote 250v d.c purely because SELV was mentioned

The question was about verifying electrical seperation between 400v 3 phase motor and. 25v SELV circuit


As for surge protection i wrote 250v d.c

 

[Adam W]

I went for 500v between SELV and 3 phase because you're testing for leakage between the two. I remembered the secondary side should be tested at 250v but you test at 500v between each side of the transformer.

I thought the surge protection was relevant otherwise they wouldn't have mentioned it, so I said 250v and explained myself by suggesting it was to prevent damage to the surge protection and misleading results.

 

[eleczar]

I just did the exam to! I think it was quite straight forward however im concerned i messed up the question about checking the carpark radial?

Does that just mean 'checks' ie cable condition, earthing, terminations etc and not any testing as it only stated CHECK.

You may of had a different paper to me as as I had to write a sequence of test on the continuity of the car park lights that incorporated 2 core SWA.

I may have struggled?

I'm sure i had a continuity one of the carpark lights too but that was the next question after the check one! God knows il just hope for the best

 

[wams]

An office wired 12 years ago, BS88 100A main fuse, wired in pvc singles in pvc conduit and trunking.
5 metal bollards in car park wired in 2 core SWA controlled by a time clock and contactor.
3 phase board next to the service head, TN-S earthing.
A new occupier had just moved in and an EICR needed to be carried out, tested at 20°c.

Can't remember much more than that.

3 phase 230/400.

I thought the scenario mentioned that the owner want a periodic inspection report so that what I wrote down along with schedule of inspectiona and tes results

 

[wams]

For both?

Yes for both, to busy concentrating on the 400v 3 phase rather than the 230v aswell

 

[wams]

I had a question asking What is the Earth Fault Loop Impedance paths for the following systems:

TN-S worth 1 mark
TN-C-S worth 1 mark
TT worth 1 mark

 

[Adam W]

I'm sure i had a continuity one of the carpark lights too but that was the next question after the check one! God knows il just hope for the best

I think there was one about a thorough inspection on the car park lights, one about doing a continuity on the car park lights, and one on testing the 32A RCBO on a ring final.

The way I view it I answered all the questions to the best of my ability within the allotted time, and there's not much more I could have done :bucktooth:

 

[Adam W]

I had a question asking What is the Earth Fault Loop Impedance paths for the following systems:

TN-S worth 1 mark
TN-C-S worth 1 mark
TT worth 1 mark

I think they wanted:
TN-S - cable sheath
TN-C-S - PEN conductor
TT - general mass of earth.

 

[CarlitoCoolest]

I had a question asking What is the Earth Fault Loop Impedance paths for the following systems:

TN-S worth 1 mark
TN-C-S worth 1 mark
TT worth 1 mark

1.
2. PEN Conductor
3.Earth Electrode

Can't remember what I put for 1.

I thought Section A was straight forward think I might of lost it though in Section B.

Long wait ahead.

 

[wams]

I carried out the carpark light as a single phase continuity rather than 3-phase (across all phases damn)

 

[vernam616]

See now i misinterpreted that earth path question, i thought it required a lot more but unsure how to write it so i actually drew out the 3 scenarios, probs lost 3 marks now, now as you mention it, it was obviously so simple


Wherever it was required to write periodic inspection report i also wrote OR electrical installation condition report

 

[vernam616]

The car park lighting was single phase,but part of a 400v system

 

[wams]

I think they wanted:
TN-S - cable sheath
TN-C-S - PEN conductor
TT - general mass of earth.

I put
TN-S = Earth and neutral seperated
TN-C-S Earth and Neutral combined
TT Consumers earth electrode to the suppliers electrode

 

[Adam W]

Reading through my notes and books earlier I couldn't find any mention of an Electrical Installation Condition report, although I think I've got the old version of GN3 and I've been using the red books.
I said 'Electrical Installation Condition Report' although I remember one of the answers given to a practice question was 'Safe condition report'.
I find it all very confusing indeed

 

[wams]

See now i misinterpreted that earth path question, i thought it required a lot more but unsure how to write it so i actually drew out the 3 scenarios, probs lost 3 marks now, now as you mention it, it was obviously so simple


Wherever it was required to write periodic inspection report i also wrote OR electrical installation condition report

I forgot about the EICR but if it was not mentioned in the question I was'nt going to detail in my answer. Even thogh I remember my tutor saying new amendment forms for the theory but old forms for the practical

 

[spark 68]

Good Luck! to all those who took this exam tonight.

It is very easy to make silly mistakes on this paper (I know I did on the Dec exam), partly due to the wording of the questions, and partly due to the exam pressure/nerves and the time limits imposed (wondering if you have enough time left).

As I said good luck!