tonights 2391 exam....(10th march 2011)

[brucelee]

yes along them lines but i hope you included the schedule of inspections and schedule of test results

 

[brucelee]

good luck to you all now begins the slow wait hope someone found a mystery copy in there bag when they got home lol
then you can check through yourself to give you some idea of how you did

anyway hope you all passed

 

[B6 7BU]

I took this to mean electrical installation certificate for new circuit, periodic inspection report for installation testing, am I on the wrong lines cos I did have to read it a few times!

No, you are on the right track.

 

[daveyzadams]

**** it ,just got ****** after it,all the hard work and revision and for me the questions tonight were,well it seeems like the whole exam is luck on the night,done that Brian Scadden exam earlier today in me local library and got 86 percent over the two sections done the last four(that I got from the forum) and done great,yet tonight I thought the questions were worded difficult,(how many sepereate DBs wre there on that installation any way I've got the last four exam papers if any one wants them [email protected] and if any one can send me some cheers stroll on June)

 

[brucelee]

thats how i felt mate when i come out as i had studied for about 4 months every day as much as i could lol and by the end of the exam i was glad it was over but fuming at the way they word things but in the end all turned out well as i passed the june 2010 exam so all worth it in the end

 

[Paul.M]

Q.a) In the shower unit, what visual inspections can you do to the c/u (4 marks)

B) explain answear to "a" (4 marks)

 

[Paul.M]

Q. What test would you do on the rcd? (8 marks) I think it said to include time, mA

Q. What other test would you carry out on the rcd (2 marks)

 

[Paul.M]

Q. Draw a diagram of a fault to earth from an office socket including labels. (15 marks)

 

[Paul.M]

The marina needed a PIR doing for the local authority and new installation of 3 lights on the gangway.

Q. What 4 documents would you provide?

Q. Who would you consult for limits and extents?

Q. Who would you give your documents to?

Can't remember the marks or the question numbers.

 

[brucelee]

Q. What test would you do on the rcd? (8 marks) I think it said to include time, mA
what size rcd? if 30mA then
did it ask for tester used etc better if you get a copy as the C&G speak needs to be read fully to understand there geeky language lol
A. Residual current device testing
test at 1/2X 15mA at both half cycles no disconnection
then test at 1 x 30mA at both half cycles disconnection in 300ms
then test at 5x 150 mA at both half cycles disconnection in 40ms

Q. What other test would you carry out on the rcd (2 marks)

functional test
press the test button on the the protective device (RCD) to check correct operation of the mechanical parts are working correctly

 

[Paul.M]

May I also say welcome to all the new members on this thread. Stick around you might just like it?

 

[Paul.M]

functional test
press the test button on the the protective device (RCD) to check correct operation of the mechanical parts are working correctly

The 8 marks question was to describe the rcd ramp test including time, mA and and if it would "activate the device". I also included the current wave for all 6 tests . The question after for 2 marks I think was asking for functional testing of the test button and for the rcd switch.

 

[Paul.M]

With the ir test isn't it best to just quote the test as in gn3? I.e. Make reference to removing any voltage sensitive equipment or link out where applicable and not leave out steps based on the fact your just testing the swa?

The way I read the question on IR test of the new lights that has an isolation switch at the base if each pole is to open the switch, link L+N and test to cpc? The swa armour was not being used as the cpc, it was a 4 core single phase and one of the cores being used ad cpc.

Next year at this rate we will all have to past a CSI course to be able to decipher the scenario never mind the bloody questions! I'm sorry C&G but not everyone has a university degree in English to be able to understand your questions. Saying that, if you put these students of the 2391 infront of the scenario you mention, 80%+ would pass because were electricians and not a Masters in English literature.

 

[john25]

Right for question 21 it asked how many certificates would be issued for the Marina and other buildings .So I put A PIR for the main Building and a schedule of inspections and schedule of test results for each of the buildings. and a EIC with a schedule of inspections and schedule of test results for the new circuit.

Question 26 didn't ask for ask for a disconnection time for the RCD tests if I remember correctly just the test current

 

[russty]

Q.a) In the shower unit, what visual inspections can you do to the c/u (4 marks)

B) explain answear to "a" (4 marks)

Mine was:-

* Any burnt or overheating cables
* Any damage to the CU affecting its intregrity
* Any missing grommets
* Any missing blanks on any spare ways

Fairly stright forward reasons for my answers i thought

 

[john25]

For that question I put Damage/Labels/correct connection of conductors and Damage to IP integrity of the DB.

 

[NMc]

Would be interesting to she the exam paper as people are remembering questions differently

 

[I am Sparkacus]

Q. Draw a diagram of a fault to earth from an office socket including labels. (15 marks)


How did people draw this? I drew 3 phase transformer, distribution board, and socket outlet. It did not state any other boards inbetween 3 phase board and radial circuit. The fault path ran along point of fault at socket, through cpc conductor labelelled r2, into MET, down earth electrode, through ground, up transformer electrode, to centre point of star transformer, with neutral connected here tool, up l1's winding, through line of supply cable, to consumer unit, through protective device, then along circuit line conductor labelled r1.
How far off the mark am i?

 

[I am Sparkacus]

Originally Posted by paul.m
Q.a) In the shower unit, what visual inspections can you do to the c/u (4 marks)

B) explain answear to "a" (4 marks)

-Correct current carying capacity of cable for protective device
-Correct order of neutrals and earths connected
-RCD present
-Damage??
??

I think I have flunked this exam, wish i was a plasterer, they dont have ever changing regs, and mathematical ******** to learn!!

 

[GrannySmiff]

Whats the two things you can ONLY find out from the DNO?

 

[russty]

Whats the two things you can ONLY find out from the DNO?

Got me thinking this one, had a stab at external earth loop impedance Ze and type of earthing supply TNC-S/TT/TN-S

 

[russty]

Q26. What 2 types of Inspection & Test for confirm for voltage drop?

Went for PSCC and PEFC, dont know if this was right carnt seem to find it in GN3 to confirm?

 

[IQ Electrical]

Q26. What 2 types of Inspection & Test for confirm for voltage drop?

Went for PSCC and PEFC, dont know if this was right carnt seem to find it in GN3 to confirm?

How about measurement and calculation?

You can physically measure the voltage drop or calculate it from cable length/size/load

 

[IQ Electrical]

Q26. What 2 types of Inspection & Test for confirm for voltage drop?

Went for PSCC and PEFC, dont know if this was right carnt seem to find it in GN3 to confirm?

How about measurement and calculation?

You can physically measure the voltage drop or calculate it from cable length/size/load

 

[IQ Electrical]

Got me thinking this one, had a stab at external earth loop impedance Ze and type of earthing supply TNC-S/TT/TN-S

If it said 'only from the DNO' then it's something you can't measure or visibly confirm so it has to be from the characteristics of the sealed supply fuse eg. BS, type, rated current and short circuit capacity.

I suppose you could get away with supply frequency.

 

[Paul.M]

Q.a) In the shower unit, what visual inspections can you do to the c/u (4 marks)

Unless I misinterpreted the question I believe it was a visual without taking the front panel off so I put i) damage, ii) labels, iii) correct size rcd, iv) correct size mcb. These are the things that we do naturaly without thinking, like tying your shoes laces but try and describe in writing how to do it?

 

[russty]

How about measurement and calculation?

You can physically measure the voltage drop or calculate it from cable length/size/load

Just couldnt think of anything else!

 

[john25]

If it said 'only from the DNO' then it's something you can't measure or visibly confirm so it has to be from the characteristics of the sealed supply fuse eg. BS, type, rated current and short circuit capacity.

I suppose you could get away with supply frequency.

I went for Ze and Maximum demand on that question

 

[john25]

Q.a) In the shower unit, what visual inspections can you do to the c/u (4 marks)

Unless I misinterpreted the question I believe it was a visual without taking the front panel off so I put i) damage, ii) labels, iii) correct size rcd, iv) correct size mcb. These are the things that we do naturaly without thinking, like tying your shoes laces but try and describe in writing how to do it?

It was a Visible check mate thats why I went for Damage/ labels Correct connection of conductors and damage to IP integrity of the DB

 

[johnmcbride]

There was a question at the start, what 3 tests would be carried out first on a three phase supply to (can't remember what it was but I had never heard of it)?

 

[john25]

There was a question at the start, what 3 tests would be carried out first on a three phase supply to (can't remember what it was but I had never heard of it)?

A 3-Phase Kiln (Iv'e never heard of it before either) so just played it safe with the Continuity of Protective conductors/Insulation resistance/Ze tests

 

[CRAGS]

Good luck all that took exam don't know what is worse the exam or the wait

 

[johnmcbride]

Ye that's exactly what I put. Am sure I read somewhere on here that someone got their exam results within 2 weeks. There was only about 10 of us doin it so I cant c it taking much longer.

 

[telectrix]

A 3-Phase Kiln (Iv'e never heard of it before either) so just played it safe with the Continuity of Protective conductors/Insulation resistance/Ze tests

a kiln is basically an oven, usually used for firing pottery. so asfaik, just heating

 

[john25]

a kiln is basically an oven, usually used for firing pottery. so asfaik, just heating

So what would the first 3 tests be on the oven then mate ???

 

[paulanderson22]

I put:

continuity of protective conductors
ir
polarity

 

[IQ Electrical]

I put:

continuity of protective conductors
ir
polarity

Spot on.

 

[paulanderson22]

Im sure everyone who sat this exam would agree that it was a bit of a nightmare! I think i did quite well bar a few things. q26 : 30ma for additional protection. half test full test both cycles and functional didnt put 5 times. 5 times needed for functional? head was battered by that point!
q2 anyone know the statutory document the dno have to abide by? surely that cant be a 2391 requirement!!
earth electrode resistance question. i answered with an earth loop tester rather that earth electrode. i think both answers would get marks but ive noticed a bit of confusion on this question, no where in the scenario does it mention there is rcd protection. the first mention is in q26. we know there will be but what are we getting marked on, something we know would be there or the scenario they have laid out?? i went through this with my tutor after the exam and he seems to think both answers would pick up marks.
After studying years of past papers i would deffo say this is the hardest exam out of them all!
i was hoping for a 15 mark question on rule of thumb values or insulation resistance!
noticed this is the first exam to have 2 questions that required description and diagrams of 2 test procedures! my hands still in cramp!
im quite confident but i dont this this exam was an easy one to pass!

 

[john25]

Spot on.

hmm Even though Polarity is the next test after IR i've seen Ze being an acceptable answer too on past paper and the Exam success book. so hopefully I still get the 3 marks as you can also confirm Polarity via the EFLI test.

 

[paulanderson22]

i thought it was. polarity can be found as a dead test and its laid out in gn3. could argue it but im sure every answer should be derived from gn3

 

[john25]

Im sure everyone who sat this exam would agree that it was a bit of a nightmare! I think i did quite well bar a few things. q26 : 30ma for additional protection. half test full test both cycles and functional didnt put 5 times. 5 times needed for functional? head was battered by that point!
q2 anyone know the statutory document the dno have to abide by? surely that cant be a 2391 requirement!!
earth electrode resistance question. i answered with an earth loop tester rather that earth electrode. i think both answers would get marks but ive noticed a bit of confusion on this question, no where in the scenario does it mention there is rcd protection. the first mention is in q26. we know there will be but what are we getting marked on, something we know would be there or the scenario they have laid out?? i went through this with my tutor after the exam and he seems to think both answers would pick up marks.
After studying years of past papers i would deffo say this is the hardest exam out of them all!
i was hoping for a 15 mark question on rule of thumb values or insulation resistance!
noticed this is the first exam to have 2 questions that required description and diagrams of 2 test procedures! my hands still in cramp!
im quite confident but i dont this this exam was an easy one to pass!

there was a BS EN 61008-1 RCD in the scenario it was at the bottom mate but I didn't see anything about it being for Fire protection

 

[paulanderson22]

****! your right there was! haha nightmare!

fingers crossed then!
in fairness im assuming very little or no marks on that question anyway!

 

[IQ Electrical]

Im sure everyone who sat this exam would agree that it was a bit of a nightmare! I think i did quite well bar a few things. q26 : 30ma for additional protection. half test full test both cycles and functional didnt put 5 times. 5 times needed for functional? head was battered by that point!
q2 anyone know the statutory document the dno have to abide by? surely that cant be a 2391 requirement!!
earth electrode resistance question. i answered with an earth loop tester rather that earth electrode. i think both answers would get marks but ive noticed a bit of confusion on this question, no where in the scenario does it mention there is rcd protection. the first mention is in q26. we know there will be but what are we getting marked on, something we know would be there or the scenario they have laid out?? i went through this with my tutor after the exam and he seems to think both answers would pick up marks.
After studying years of past papers i would deffo say this is the hardest exam out of them all!
i was hoping for a 15 mark question on rule of thumb values or insulation resistance!
noticed this is the first exam to have 2 questions that required description and diagrams of 2 test procedures! my hands still in cramp!
im quite confident but i dont this this exam was an easy one to pass!

You must perform the 5X I delta n test on a 30mA RCD/RCBO.

The DNO document is ESQCR 2002

Traditionally, the EFLI tester was used on TT earth electrodes and the earth electrode resistance tester on earth electrodes for generators.

 

[paulanderson22]

thats why i went efli because the only knowledge ive got of the electrode tester is on generators. plus i dont know enough detail of that test procedure to pick up full marks!

i hope everyone labeled the general mass of earth on their diagrams!

 

[john25]

You must perform the 5X I delta n test on a 30mA RCD/RCBO.

The DNO document is ESQCR 2002

Traditionally, the EFLI tester was used on TT earth electrodes and the earth electrode resistance tester on earth electrodes for generators .

Yep there the answers I put down on the relevant Questions used a EFLI tester cause there was a RCD protecing the TT system and even though I said I would do a 10-Step safe Isolation procedure I screwed up by carrying out a single phase test grr.

 

[john25]

thats why i went efli because the only knowledge ive got of the electrode tester is on generators. plus i dont know enough detail of that test procedure to pick up full marks!

i hope everyone labeled the general mass of earth on their diagrams!

arrrrrgh NO I did not lol. oh well the way im looking a this now is that it did not cost me anything to do the course and now I know what to type of questions to expect if I need to re-sit it again

 

[IQ Electrical]

hmm Even though Polarity is the next test after IR i've seen Ze being an acceptable answer too on past paper and the Exam success book. so hopefully I still get the 3 marks as you can also confirm Polarity via the EFLI test.

If you're looking at page 39 in Exam Success, you'll see that Ze is only listed in the first 3 tests on a ring final and that is because polarity is already confirmed in the ring final continuity tests.

 

[paulanderson22]

looking at answers people are giving i have missed a bit of detail out! nightmare!
i paid nearly £800 for this course and it looks like ill be paying a resit!!

 

[SMB]

Good luck with your results guys.

The 2391 is a difficult exam to pass indeed.

It took me 45 working days to get my results, the waiting is a killer I know. I spent so much time going over my answers in my head during that waiting time. Then 3 months later I was given the date for my 4 hour practical assessment. That was a definate flaw in my course!

All the best, I hope it goes well for you all.

 

[Paul.M]

Q. Why can't you use Zs - Ze to work out your R1+R2?