unusual voltages on 3 phase

[NozSpark]

I bet you if you told them that you needed to investigate an anamolus reading that could be caused by a fault which could cause an electric shock, fire or damage to equipment then I recon they'll soon let you shut it down

 

[ProDave]

I bet you if you told them that you needed to investigate an anamolus reading that could be caused by a fault which could cause an electric shock, fire or damage to equipment then I recon they'll soon let you shut it down

+1

If the fault is so bad, one phase is appearing to go up to 400V, then I'm surprised you are not investigating equipment that's blowing.

I had a similar thing a few years back when a big house on a 3 phase supply had to have a temporary genny supply when the overhead lines came down. The DNO wired the genny wrong, with the neutral to one of the phases. The first sparky who checked it was stumped why stuff kept blowing and tripping. It took me about 10 seconds with a volt meter to suss the problem and I went out and hit the kill switch on the genny and called the DNO back. The DNO guy, re started the genny, "tested" it with his volt stick and said what's the problem guv? I had to show him the problem with a volt meter. I guess the first sparky to look at the problem did the same?

 

[bassman]

I am in the works dept mate, well away from the cons!Have an escort though in 2 of the 3 the last is Butlins with green jogging bottoms, i.e. and open one!

I cover 4, 2 cat b, with some cat a, there the security is tight.

They look after you though.

Hi Sidewinder, what are they as we may have met as I tend to go round the establishments,the 4 you mention are they Swansea,Cardiff,Usk & Precoed.

I also have to go to Parc.(Nr Bridgend)

Which one has the A's as I do the cat A's as well.

 

[Sidewinder]

OK I think I know who you work for then?

If you are a spark (why else would you be on here!) then your company is named after a mountainous place north of the border?

You do most of the electrics for the prisons then?

Swansea had Cat A in but he left about a week ago. Apparently they have the odd one in.

Cardiff have had the odd Cat A's but I'm told not all the time, last time I was there there were none in.

I don't do Parc, though I know of the place. One of my neighbours works there & one of my Uni Prof's was also a lay preacher who used to "work" there.

I'm not a regular in there as I specialise in certain types of equipment really.

If you work for who I think you work for then my details have been passed on to your boss, I hope as I may be able to help him out with some stuff.

Being a one man band I don't have the resource to support work on the landings really.

I have not met any of the other contractors that go in to be honest.

 

[Adrian41uk]

Another possibility, since no equipment seems to have been distroyed.......

If this is a 3phase board which is only feeding three phase loads & the neutral has never been terminated. I have seen a situation before where the neutral was present at the load end but was open at the supply end (MEM switch fuse with the neutral link missing - guess somebody never put it back after testing!). This won't show itself if no single phase loads are present, since the 'artificial' neutral will float with no consequence & give you the strange kind of readings that you are seeing.