main incoming on a tt

[egginyourface]

went to a job couple of days ago where supplier hadnt supplied earth and looks like it was taking from the water pipe.

Mains water had been up graded to plastic so that wasnt doin the job anymore.

So somewhere down the line someone had come along and stuck a spike in.

I did a test and got a reading of 5ohms. No rcd protection was present. So I told the customer to call energy supplier to come have a look.

To cut a long story short they issued a danger notice and cut the supply at the head by pulling fuse.

Customer calls me with engineer there and tells me theres nothing they can do other than upgrade it to pme but would cost £3,000.

What they offered was that they could strip back sheathing and let me attach earth clamp. they tested the loop impedance from the outer sheathing and they were getting .5ohms.

I refused to use an earth clamp on the sheathing as its illegal for me to mess around with suppliers side of meter.


Is this allowed? Ive seen it many times but never actually put a clamp on the incomer.

Shouldnt it be sweated on by them??

 

[sedgy34]

earth electrode would have gone in for me then upgrade DB for rcd split alot cheaper than £3,000 they wanted from your customer

 

[Engineer54]

A TT install is the very last option you would want to go for!! I would be asking at the very top, how they have calculated 3000 quid to PME a domestic installation!! So what earthing system does have all the other houses have in this street?? For a start, I'd be asking neighbours if i could have a quick look at the service heads... If all are PME or TN-S, then there would be some explaining to do as to why they are quoting 3000 quid, for a job that can be done during the service head up-grade at no extra cost to them whatsoever....

If the DNO themselves got a 0.5 ohm, and actually told you to fit your own earthing means to the sheath, then at the end of the day i would be inclined to do just that with the use a constant force spring earthing clamp. No tools required, absolutely no chance of damaging the lead sheath, and a decent earthing point for the installation....

Absolutely amazes me at times here, how fast some will just bung in a twig for an earth rod, be happy with a 200 ohm Ra and walk away ''actually thinking'' they've done a good job!!!

 

[andydj99]

If they are getting .5 from the sheath would this not be suitable as a TN-S?

that should be ok as maximum is .8 for a TN-S

 

[applemac]

talking of constant spring clamps, anyone know where i can buy a set? hand to have,quicker than dno dates and comply with regs,

dno upgrade to pme and shove one on as well as connection to neutral looking at the one the did one my gaff.

didnt pay for it as no earth and old head...

 

[Guitarist]

Seems the service one receives varies wildly between DNO's. Eon will fit a DP isolator free of charge, plus the guy who did it told me his instructions were to fulfil the customers wishes as much as possible within reason.
I actually felt like I was getting a good service for a change.