testing for Ze and PFC. - Page 2 - Electricians Forum | Electrical Forum | An electrical forum for electricians in the UK

Shakey · 18-04-2008

Quote:

Originally Posted by Ross Trician

Shakey would that mean then that if I installed a suitable spike etc at the incoming supply then I would have to ensure that all the instalations on the system (not just the 2 areas I have worked on) are correctly earthed and terminated etc throughout? and that they have adequate Ze, Zs, pfc tests etc?

What do you mean about the rcd wont work for the instalation?

( apologies for the many questions but it is helpfull when you get answers from someone who knows them)

Ross, sorry, the RCD will work, but you should not use it

Look at 314.1 (got the 17th in front of me now, but its the same as in the 16th)

"every installation shall be diveided into circuits as necessary, to:

(i) avoid hazards and minimize inconvenience in the event of a fault

(iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit

(iv) reduce the possibility of unwanted tripping of RCD's due to excessive protective conductor currentd prodeuced by equipment in normal operation)

so for these three reasons, you cant use front end RCD's, unless they have lower value RCD's downstream, (like in a TT), but under the 17th, that will mostly go anyway

in answer to you first question, the Ze is ONLY at the origin, everythin else will be Zs - and yes, you take responsibility for the lot. The pint is, to certificate your work, as you know, you HAVE to include the supply characterisitics, Ze, PFC etc, which, unless you spike at the origin (or get PME installed etc) you wont have

sorry fella!

Ross Trician · 18-04-2008

cheers Shakey and all of you for the coments and help, yes I think it is the tip of the ice burge too,
I will see if a pme is possible and if not consider options from there.

It also depends I supose if they want to do anything about it, you know the old "it's always been like it and has always worked fine" scenario.

to be honest it is quite possibly one of those jobs that you perhaps want to avoid, more trouble than its worth etc...lol.

Shakey · 18-04-2008

Quote:

Originally Posted by Ross Trician

cheers Shakey and all of you for the coments and help, yes I think it is the tip of the ice burge too,
I will see if a pme is possible and if not consider options from there.

It also depends I supose if they want to do anything about it, you know the old "it's always been like it and has always worked fine" scenario.

to be honest it is quite possibly one of those jobs that you perhaps want to avoid, more trouble than its worth etc...lol.

yep I think its one of those as well Ross....

I have no doubt they will not want to do anything about it - but that also means that you should follow their lead!!!!

Had8Lives · 25-05-2008

I agree Steve.

BillR3 · 12-06-2008

Just a word of warning if you are going to fit earth rod(s)

As you know our 4 legged friends are susceptible to electric shock more than humans due to their contact with the ground so you will have to barrier off the earth rod(s) location(s) if you end up using your TT system to keep them from danger.

BillR3

jibtech · 25-06-2008

yes possibly the funniest part of college when the lecturer explains the ground fault voltages can easily floor a heffer

and then he explains that cows are curious beasts and the whole herd will more than likely wander over to take a look .......thud....thud...thud....thud

hahaha at 3000 quid a cow maybe more?? you better hope you can run faster than the farmer and his shotty

ps i think i would avoid this job unless the clients reaction was such that i was convinced he wants to put it totally right and proper and pay for it.cant see that happening though