earthing

Only time I've done this has been using the two separate CPCs of a RFC using different terminals inside the D.B as per 543.7.1.204 I've been asked to test a load of high integrity radial circuits with two separate (different sized) CPCs. My question is, in the box which asks for the CSA of the...

I've been in an ongoing debate regarding earthing of a control transformer and i'd like some other opinions. 690 primary, 120v secondary supplying control circuits (contactors/DC convertors etc), the neutral is tied to earth - My issue is the location that it is tied to Earth. As far as I know...

Hi, I've come across this strange setup on a set of flats I'm doing work on and wondered what people think. There are 4 flats on the 1st and 2nd floor (ground floor is a shop) with their own supply from the street. The supply enters the building from underground at the bottom of the stairs, a...

Hello, can anyone advise on bonding of extraneous conductive parts when supply is from a generator run parallel with distribution network? There'll b a 200kva generator supplying spray booths that have a gas supply to them. The metal pipes aren't underground but connect to tanks outside sitting...

Somewhere along the line I picked up a suggestion from a forum posting or two that the DNO does not like you to connect an earthing rod to his "earth" - even though it is effectively just creating yet another, local to your installation, earthing point for the multiple ones already assumed to...

Hi there, We will need to earth a Faraday cage room in an experimental work, do we need to certify the job? Can it be only earthed into the plumbing pipes if available (Bonding?)? If there are no pipes around should we earth it into a mains circuit using a junction box or surface box for...

Hi, just a quick question... I’m at the stage now where I’m being pretty nosey at other people’s consumer units/supply set ups etc to further improve my understanding and recognition of the different earthing systems found in domestic properties. The image below was taken at a member of my...

Here's a question that I was asked earlier. If you have SPDs installed in a DB is it permissible to terminate the main earthing conductor into the SPD first then the DB earth bar? Or must it be terminated in the DB earth bar first then the SPD?

I'm working on a Job where the earth is TT there is a sub main fed by 16mm twin and earth if I put a earth rod in at the submain position should I connect the cpc of the submain to the earth rod at the sub dB or just use it as a cpc and earth the sub board separately ?

Hi, looking to broaden my knowledge regarding earthing and protection. EA Technology have been mentioned as having decent courses in this area. I would like to hear from anyone who has been on training with them even if not in this field as often a standard will run through most training...

On a job this evening just taking a look around and meeting customer as wants downstairs rewired. Only collecting keys before i go back and do a few tests and quote fully. Appears at sometime to have been TNS but changed to PME? Instead of earth and Neutral joining in the cut out. They are...

Hi recently was on a job carrying out EX inspections on three phase motor at a pharmaceutical plant. The supply cable going to the motors does not have a core for the earth they have used the braid/SWA of the cable for earthing. So entering the three phase motor with EXe cable glands terminating...

Hi new here so take it easy chaps !! A client of mine wishes to supply their catering van from a new generator they are purchasing, I believe it is single phase 7.5kW Inverter style generator with a 32 amp socket outlet. My query is about the earthing to the van. The van has a DB inside with a...

Hi just a question regarding the supplementary earthing in a hazardous area. When you have a earth boss welded to a piece of steel which is the structure of the building to give a bonding connection for equipment in that area they usually say that only two earth cables per earth boss. Is there...

I'm going to replace the consumer unit for a customer in rural Oxfordshire. The supply comes in overhead, drops down a telegraph-type pole into the ground, and runs about 2m to a recessed box in the wall (perhaps coming up in the cavity). I can't find the earth rod - probably entirely...

While ripping the old bathroom fittings out I noticed that none of the pipework or fittings were earthed. Should they be earthed and if so what is the preferred method?

Hi just after opinions on this one got three 3 phase supplies all 25mm 4 core swa, armour not been used for earth would you run a seperate 16mm earth for each supply or just loop all the earths from 1 16mm all the supplies are right next to each other

Hi I’m new to the forum & just a DIY’er! I’m running a 15m length of 2.5mm 3 core (twin & earth) SWA to our decking at the back of the garden for a double socket. Must the steel wire armour be earthed using the banjo or is the CPC core sufficient? Thanks in advance! J

Hi all, I am an amateur and have been checking EF measurements around my house. The computer seems quite a large source and I'd like to reduce my exposure. Can a keyboard/mouse be earthed/grounded with a contact wire on the item running to Earth on socket/radiator? I thought of using an...

Hello, I am converting my ceiling downlighters to LED. The old MR16 50W halogen bulbs come with a 12v transformer. I plan to cut the LV cable just before the transformer, then strip it and wire it into the new GU10 LED lamp holder. This means the new GU10 lamp holder will not be earthed. Looking...