TT change o PME???

[redrocket10000]

Hi Guys, Called out yesterday to a fault at a rental property where a cowboy has been at work. Fault I was called out for was that whenever something was switch on then the rccd would trip also upon inspection the rccd test button would not operate. Now upon contacting the cowboy to find out what he had done, He had changed the the system earth from TT to PME. This part of the job look ok except that there was no indication of the system actually being PME. so I unearthed the old rod and reconnected it, this then cleared the tripping and test button faults although the Ze is now at 400 ohms I will endeavour to get that value lower. All circuits had IR readings well above pass values L-E, N-E, L-N. So my question is, would connecting to a PME system that is not PME cause the tripping problems and test button inoperation because I cannot find any other reason for this happening. Any help in explaining this would be much appreciated thanks.

 

[jamesBoater]

Why did this guy think he could make his own PME connection? This is down to the DNO!

 

[telectrix]

could be the floating earth causing the problem. and why was the cowboy messing around with DNO equipment.? sounds like you may be following him on other jobs. he's obviously got no clue what he's doing.

 

[redrocket10000]

I Believe its a case .of a little bit of knowledge is dangerous thing and the earth rod was in his way.

 

[jamesBoater]

He just sounds dangerous, not sure about the whole knowledge thing.

 

[telectrix]

try a couple of screwed 5/8" rods coupled for depth. drive in at least 3' from walls.

 

[Geordie Spark]

I Believe its a case .of a little bit of knowledge is dangerous thing and the earth rod was in his way.

Was he a Time-Served cowboy or a 5 Week Wonder cowboy??

YeeeeeeeeeeeeHaaaaaaaaaaaaaaa!!!!!!!!!! :cowboy:

 

[tony mc]

So did you find the neutral earth link for the diy PME as your explanation is a little confusing. He had changed the the system earth from TT to PME. This part of the job look ok except that there was no indication of the system actually being PME .

I take it you didn't tighten any loose connections which was possibly causing the original fault !

 

[redrocket10000]

He had connected a 16mm earth cable from the distributors fuse cut out neutral block to the MET as do the REC...although the screw that holds the neutral block cover in place was missing making the sliding cover removeable without a need to remove the main fuse. The first thing I did was check terminations for tightness, then IR tests on all the circuits, which were all good. There was no PME label on the main cut out.

 

[driverman]

There may be no PME available in that area. Is it overhead supply or underground supply? If O/h supply you should be able to see if PME available by looking at the poles carrying the O/H supply. Should be PME labels about head height on each pole. Also about every other pole there will be an earth connection to ground.

 

[Knobhead]

So do you propose to keep this PME set up or report it to the DNO?

 

[tony mc]

Thanks.
So how have you left the premises have you got the Ra down to a acceptable level. I know you got the call re a tripping RCD but is it a 16th or 17th edition board re the upfront RCD if needed now for other ccts due to the disconnection times being way out! I still don't think the DIY PME was the reason for the RCD tripping and the test button not working IMO!

 

[Guitarist]

So are you saying that it's now back on an earth rod with an Ra of 400 ohms?

 

[trev]

Crikey!