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Hi I’m looking to confirm something quickly, I’m due to sit a practical exam next week run by napit , this is to prove competence as haven’t got a testing and inspection exam .

I understand the test procedures and looking at course content etc I have to carry out the following

1. electrical installation condition report
2. Initial verification
3. Minor works

now my question is when carrying out an initial verification when should you test the

Ze , pfc ??? Now under gn3 this states to carry Out in this order - conti of cpc, including main and supplementary
Conti of ring circuits
InsuLation testing
Polarity

then carry out earth fault loop impedance, is this where I would do my Ze and Zs tests???
Then pfc test????

used to looking at condition reports so generally do my ze test once locked of main switch - but don’t want to fail exam on initial verification so need to make sure I test the ze at right time. Just seems to be a long way into testing before ze is taken .
 
Alright mate,

I take it you’re doing the Napit 7232 to prove competence? If so, read below.

You’ll be given a bay containing a 3P and single phase boards containing various circuits, containment, bonding, sup bonding and wiring types, to simulate something along the lines of a commercial premises downstairs and a residential dwelling above it.

First up you’ll have half an hour to carry out a visual inspection and pick up as many faults as possible, there’s about 12 and they like you to get at least 10. The rest you’ll pick up while testing.

Then you’ll do an EICR on the 3P board in the morning and an EIC on the SP board in the afternoon. You’ll also do a MWC for a spur that’s been put in on the RFC on the SP board.

At this point I’ll note that the 3P board is supplying the SP board.

Go through the testing sequence as you would.

Safe isolation
Continuity of main earthing conductors
Continuity of Bonding and sup bonding
Continuity of circuit protective conductors and RFC’s
IR
Live polarity at incoming tails
Ze
PEFC
PFC
Phase Rotation

Check over the board, make sure you’ve left nothing hanging out, replace guards and board cover.
You can now carry out Zs of circuits, RCD tests and functional tests.

IMPORTANT - Ensure the cover is on your 3P board and your SP board locked off before you take a Zs reading there, as although they’re right next to each other, in reality, ones in a basement and ones up the stairs. You’ll also need to prove safe isolation on the SP board prior to taking the reading.

Time wise, I think you get 2 hours for the EICR and 2.5 hours for the EIC and MWC which is plenty as on a 2391 course you only get 2.5 hours to complete both.

Good luck with but all; and if I’ve put phase rotation in the wrong place, I’m sure someone will be here to correct me shortly.

One more thing - SAFE ISOLATION, SAFE ISOLATION, SAFE ISOLATION
 
Alright mate,

I take it you’re doing the Napit 7232 to prove competence? If so, read below.

You’ll be given a bay containing a 3P and single phase boards containing various circuits, containment, bonding, sup bonding and wiring types, to simulate something along the lines of a commercial premises downstairs and a residential dwelling above it.

First up you’ll have half an hour to carry out a visual inspection and pick up as many faults as possible, there’s about 12 and they like you to get at least 10. The rest you’ll pick up while testing.

Then you’ll do an EICR on the 3P board in the morning and an EIC on the SP board in the afternoon. You’ll also do a MWC for a spur that’s been put in on the RFC on the SP board.

At this point I’ll note that the 3P board is supplying the SP board.

Go through the testing sequence as you would.

Safe isolation
Continuity of main earthing conductors
Continuity of Bonding and sup bonding
Continuity of circuit protective conductors and RFC’s
IR
Live polarity at incoming tails
Ze
PEFC
PFC
Phase Rotation

Check over the board, make sure you’ve left nothing hanging out, replace guards and board cover.
You can now carry out Zs of circuits, RCD tests and functional tests.

IMPORTANT - Ensure the cover is on your 3P board and your SP board locked off before you take a Zs reading there, as although they’re right next to each other, in reality, ones in a basement and ones up the stairs. You’ll also need to prove safe isolation on the SP board prior to taking the reading.

Time wise, I think you get 2 hours for the EICR and 2.5 hours for the EIC and MWC which is plenty as on a 2391 course you only get 2.5 hours to complete both.

Good luck with but all; and if I’ve put phase rotation in the wrong place, I’m sure someone will be here to correct me shortly.

One more thing - SAFE ISOLATION, SAFE ISOLATION, SAFE ISOLATION
Perfect so if I stick to the correct sequence of tests you have put above for both boards that will be ok? Napit assessor seemed to think I should do the ze and pfc tests when I have locked off main board incomer? As these should be done with main switch on.
Was told we don’t have access to the isolator for the 3 phase board so disconnecting the earth incoming for ze test is after live polarity test so guessing just switch main switch back off
 
Your board should be locked off until you put the cover back on.

Carry out dead tests first. Then live polarity at the incoming tails. Then Ze, PEFC and PSCC. As stated above.

I should have put PSCC instead of PFC on my earlier post above.

Don’t forget to take 3 readings of each on the 3P board; and to double the highest PEFC / PSCC reading to get your PFC (I think that makes sense).
 
Perfect so if I stick to the correct sequence of tests you have put above for both boards that will be ok? Napit assessor seemed to think I should do the ze and pfc tests when I have locked off main board incomer? As these should be done with main switch o
Was told we don’t have access to the isolator for the 3 phase board so disconnecting the earth incoming for ze test is after live polarity test so guessing just switch mai
Your board should be locked off until you put the cover back on.

Carry out dead tests first. Then live polarity at the incoming tails. Then Ze, PEFC and PSCC. As stated above.

I should have put PSCC instead of PFC on my earlier post above.

Don’t forget to take 3 readings of each on the 3P board; and to double the highest PEFC / PSCC reading to get your PFC (I think that makes sense).
Perfect thank you very much really helpful useful reply
 
When I did mine, four years ago, there were some right numpties in there.

You sound reasonably knowledgeable so don't worry too much .

Come on then guys getting conflicting answers from mates who are sparks .

so on my practical exam tomorrow when doing an EICR where would you do the external earth fault loop impedance test????? We have no access to the isolator so can only lock off via main incomer on 3 phase board.
Would you do continuity testing, ring testing, insulation resistance testing, polarity , then when ready to do zs testing of circuits do ze just before that??? I’m being told to do external fault loop impedance test as soon as I remove the cover before any further testing??? And also to the pfc tests then as well then move onto continuity of circuit protectors , But this is different to the test procedures for initial verification and wondered the correct way.
Really don’t want to fail this by doing something wrong -
 
Come on then guys getting conflicting answers from mates who are sparks .

so on my practical exam tomorrow when doing an EICR where would you do the external earth fault loop impedance test????? We have no access to the isolator so can only lock off via main incomer on 3 phase board.
Would you do continuity testing, ring testing, insulation resistance testing, polarity , then when ready to do zs testing of circuits do ze just before that??? I’m being told to do external fault loop impedance test as soon as I remove the cover before any further testing??? And also to the pfc tests then as well then move onto continuity of circuit protectors , But this is different to the test procedures for initial verification and wondered the correct way.
Really don’t want to fail this by doing something wrong -

Whoever is telling you to do Ze first is wrong. They may do it out in the field when testing themselves to save time, but you’re under exam conditions so do it in the correct sequence of tests as I stated earlier.

There’s probably an MET on the rig you’ll use, so you can disconnect there to remove parallel paths and then test.

Failing that, you’ll have to remove main earth from the earth terminal inside 3P board and use that to test.

If you go through the correct sequence, you won’t miss anything and set yourself up to fail.
 
Whoever is telling you to do Ze first is wrong. They may do it out in the field when testing themselves to save time, but you’re under exam conditions so do it in the correct sequence of tests as I stated earlier.

There’s probably an MET on the rig you’ll use, so you can disconnect there to remove parallel paths and then test.

Failing that, you’ll have to remove main earth from the earth terminal inside 3P board and use that to test.

If you go through the correct sequence, you won’t miss anything and set yourself up to fail.
Thanks exactly what I was thinking but wanted to ask again as been told 3 or 4 times to do it first and my first thought is no that’s wrong way to do it. Thank you once again for your help
 
Thanks exactly what I was thinking but wanted to ask again as been told 3 or 4 times to do it first and my first thought is no that’s wrong way to do it. Thank you once again for your help
It's clearly wrong to do Ze first as you should always carry out dead tests first.
 
Whoever is telling you to do Ze first is wrong. They may do it out in the field when testing themselves to save time, but you’re under exam conditions so do it in the correct sequence of tests as I stated earlier.

There’s probably an MET on the rig you’ll use, so you can disconnect there to remove parallel paths and then test.

Failing that, you’ll have to remove main earth from the earth terminal inside 3P board and use that to test.

If you go through the correct sequence, you won’t miss anything and set yourself up to fail.
First thing I do, at the earliest opportunity, when doing any significant work is a diagnostic Ze/Zdb.

You simply cannot progress without doing so.

"Er, sorry but that £X000 worth of work I just did, well, I won't be energising it as you have a poor earth somewhere but I'll gladly charge you to sort it out"

Much more professional to walk in, do a diagnostic Ze/Zdb (one without having to disconnect parallel paths and shut the whole shooting match down*) and then carry out your works with a degree of certainty that you can turn it on afterwards.


*I know, I know you can still have your pant pulled down, I tend to do a lot of diagnostic work during working hours and return out of business hours to complete works, and can power down to do a proper Ze.....yada, yada, yada.

Where were we?
 
That's the problem with most perceived correct sequence testing, it does not take into account that the work is carried out in real time and the convenience/inconvenience to the customer is ignored.
 

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