PME

[Evans Electric]

In this area (North B,ham) the old cable sheath network earth connections are breaking down under ground.

So, someone in the next road found me in the Yellow Pages today, burning smell in hall , thinks its the fuseboard. So I pop round , new board needed , get them up and running temporary.

Thing is , it was the third time I've come across a PME conversion with a Henley block fitted in the neutral and the main earth connected to it.

No link to the lead sheath ( although would be high impedence anyway) but no evidence of digging up or rodding outside. Now bear in mind the DNO will often say "Sorry you can't have a PME in that area the network won't stand it"

You'll have to TT it .

HHHHmmmm how come they can just connect the earth to the neutral then ??

The attitude of the DNOs has always been interesting to say the least. I'm doing a job out in the sticks at the moment in Warwickshire , customer is paying EON

 

[Zeespark]

DNO's need shooting half the time.

Andy

 

[ianmacd]

Only half?

 

[nsbs]

DNO are a law on to themselves.

 

[steptoe]

typical of a so-called 'PME' system in this country,

would be interesting to bang a rod in and measure your resistance to N, should be virtually 0 ohms if proper PME

 

[mikep]

I done a job in Wimbledon They put in a new PME, dug the road back to the main junction to join it in, the state of the existing SWA for the road was virtually non existent I think the whole grid will be in big trouble if it's all looking like that.

 

[Chris_81]

I phoned uk power the other day about a job. Asked them if they knew if it was pme or not. Dopey on the phone said, no but we can come and test it... So I asked how... Earth loop Test on the cut out! Pointed out to her that doesn't prove anything as a tns system can often register low enough to be a pme reading. She didn't have an answer to that. Told the customer if it was me I'd rod it rather than trust them to do anything with it!!

 

[steptoe]

ah, but a Ze on the cut out across E and then N will have identical readings on TNCS ! TNS will vary, even if just slightly, well I have never come across TNS yet with identical readings.