Shower feed wired in wrong

[1stfix2ndfix]

I was wondering if anyone can answer this one for me. I'm an electricians mate, I did ask the guy I'm with but he couldn't give me an answer.

So after he changed the board and I did the bonding I get to go round testing. Whilst taking the zs of the shower I noticed immediately upon removing the over that the feed had been wired up wrong. The live was with the live but the neutral from the feed was wired up to the earth terminal/cable in the shower and likewise the earth from the feed was wired up to the neutral terminal and cable of the shower. Now spotting this I asked the customer who had wired this up as they have done it wrong and I was told the fire fitter lol. She then asked me why it had worked and was still working. I didn't really have a answer and nor did the guy I'm with if I'm honest so I'm just wondering if anyone knows the answer to that one. Was it unsafe and were they just lucky. I felt a right idiot not knowing the answer but hopefully next time I'll be able to fill em with confidence in my response

 

[Plonker 3]

A very lucky escape, if the shower had developed a earth fault there is a good chance the pipe work could become live or other class 2 equipment, also any spark working in the DB could have been at risk if they were working in the DB. I take it that there wasn't a RCD or RCBO fitted to the circuit befor the DB change?

The reason it would still work is there is still a return path via the earth cable rather than the neutral.

 

[uksparks]

I saw a similar thing with an immersion switch, someone had done the same.

 

[Silly Sausage]

WTF is a 'fire fitter' ?

I didn't really have a answer and nor did the guy I'm with

Was he your boss, ie The Electrician? He really should know the answer! :smilielol5:

 

[1stfix2ndfix]

I'm guessing it was the person who fitted there fire lol but I could be wrong. Dillb cheers for the knowledge mate and yes Archie I agree but he didn't seem to so I thought if ask on here and I got a pretty good answer so I'm happy

 

[1stfix2ndfix]

What made it worse was the two screws supposed to hold the cover on at the top were missing and it could be pulled back a good couple of inches. Lucky indeed as it was a rewireable db originally

 

[uksparks]

also any spark working in the DB could have been at risk if they were working in the DB.

Can you clarify how it would be dangerous to the spark on the assumption that safe isolation of supply had been followed.

 

[Plonker 3]

Can you clarify how it would be dangerous to the spark on the assumption that safe isolation of supply had been followed.

So you think it's ok as safe isolation should always be followed?

 

[Brightspark2]

A very lucky escape, if the shower had developed a earth fault there is a good chance the pipe work could become live or other class 2 equipment, .
.

Am I having a slow brain moment here?. Thats going to happen anyway as they are all connected...

 

[Brightspark2]

So you think it's ok as safe isolation should always be followed?

Well if its not then any electrician working in there is going to be at risk anyway...

 

[telectrix]

surely if a new board has gone in the shower will be on RCD. when you then switch the shower on , the RCD will trip as current will be flowing L - E , thereby causing a huge imbalance.

 

[1stfix2ndfix]

Can anyone give me an example of a earth fault on a shower. Eg rat gets into shower unit and chews through a cable

 

[Plonker 3]

Now it will yes, but it should be picked up on the testing before the circuit is energised anyway.

 

[Silly Sausage]

Can anyone give me an example of a earth fault on a shower. Eg rat gets into shower unit and chews through a cable

Water is the one that springs to mind.

 

[telectrix]

only way that would have been picked up is by opening the shower and doing a R1+R2 or just a R2. who does that for a board change?

 

[1stfix2ndfix]

That could not have happened as the first thing he does is to cut into the tails and pop a rcd in the middle. If this trips out we know we've got problems. So that is weird either he didn't do it (not likely) or there's something else as the feed coming in was Deffinenty wired up l-l n-e and e-n.

 

[Plonker 3]

only way that would have been picked up is by opening the shower and doing a R1+R2 or just a R2. who does that for a board change?

What about a Zs?

 

[1stfix2ndfix]

Honestly mate no idea. Guessing water get inside the cover

 

[1stfix2ndfix]

Honestly mate no idea. Guessing water getting inside the cover

 

[Brightspark2]

but it should be picked up on the testing before the circuit is energised anyway.

Exactly, so what testing was done?

 

[trev]

That could not have happened as the first thing he does is to cut into the tails and pop a rcd in the middle. If this trips out we know we've got problems.

He does what? Is that his idea of pre change testing?

 

[Brightspark2]

That could not have happened as the first thing he does is to cut into the tails and pop a rcd in the middle. If this trips out we know we've got problems.

The plot thickens...

So before he changes the board he sticks an RCD inline with the tails and if this trips you know you have problems?...

ha ha no way!...is there no testing carried out?...(other than the bang test)

 

[Brightspark2]

He does what? Is that his idea of pre change testing?

Less words and you got there before me, you win this time....

 

[Brightspark2]

Honestly mate no idea. Guessing water get inside the cover

Water inside or an internal fault could cause an earth fault...

 

[1stfix2ndfix]

Testing seems to be cut into the tails and put a rcd in. If it trips then we've got problems if not good to go.

So I'm wondering should the rcd have picked up on this

What tests should of been done and what one would have shown me that the nutral and earth were mixed up in the shower unit before I even looked in there?

 

[telectrix]

even doing that bodge, the RCD would hold until the shower was turned on. :furious3:

 

[Silly Sausage]

Is your boss an ex darts player? :smilielol5:

 

[1stfix2ndfix]

Eye. And then take the main fuse out but I'll do that anyway @ trev.

 

[1stfix2ndfix]

Nice one getting more clued up by the minute

 

[telectrix]

Testing seems to be cut into the tails and put a rcd in. If it trips then we've got problems if not good to go.

So I'm wondering should the rcd have picked up on this

What tests should of been done and what one would have shown me that the nutral and earth were mixed up in the shower unit before I even looked in there?

no way of finding that fault without opening the shower unit apart from RCD tripping as soon as the shower was used. i've already said that if you read my previous posts.

 

[Brightspark2]

Testing seems to be cut into the tails and put a rcd in. If it trips then we've got problems if not good to go.

So I'm wondering should the rcd have picked up on this

What tests should of been done and what one would have shown me that the nutral and earth were mixed up in the shower unit before I even looked in there?

http://i.stack.Upload the image directly to the thread.com/jiFfM.jpg



I cant believe someone does that. An R1+R2 or R2 would of picked it up, one of the first tests that should of been carried out.

Installing an RCD in line is going to take longer than carrying out that test. As Tel says it doesnt prove much either because it would have to be switched on for it to trip. It is not the right way to do things at all.

 

[1stfix2ndfix]

surely if a new board has gone in the shower will be on RCD. when you then switch the shower on , the RCD will trip as current will be flowing L - E , thereby causing a huge imbalance.

Cheers I can now suggest things

 

[1stfix2ndfix]

surely if a new board has gone in the shower will be on RCD. when you then switch the shower on , the RCD will trip as current will be flowing L - E , thereby causing a huge imbalance.

Cheers

 

[telectrix]

be honest though, how many of us have opened a shower to get a R1+R2 before doing a board change?

 

[1stfix2ndfix]

Sodding phone.

So r1 + r2 would be done at the shower

 

[1stfix2ndfix]

I would of seen It by then

 

[1stfix2ndfix]

If you've got to do it for 8 circuits say then it would probably be quicker

 

[Octopus]

Is it me or is this thread more than a little bit confusing, that said its Lofty or now know as 1st2nfix - so nothing new there

 

[HandySparks]

...the first thing he does is to cut into the tails and pop a rcd in the middle.

Damn sight easier to just measure the differential current in the tails with an earth leakage clamp meter. No cutting of cable required.

It's one of the first things I do when an RCD tripping problem is reported.

 

[Kris]

Sorry to be a thickoo guys just reading this interesting thread and wondered whats an r1 + r2 ??