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Discuss SSE 3-Phase Upgrade Gone Wrong! in the Commercial Electrical Advice area at ElectriciansForums.net

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Hello,

Looking for some advice following a botched 3 phase upgrade today. Some background:
  • Commercial unit originally fitted out (4 years ago) with single phase main supply feeding into 3 phase DB. 2nd DB run off breaker to service single phase requirements (small kitchenette, lighting, sockets, shutter door motor)
  • Electrician has prepped site with new 3 phase requirements, mostly just 1st fixed. New 3 phase main switch with consumer side terminated as requested by SEE. Cables clearly labelled.
  • SSE (team 1) have brought new 3 phase supply cable into building and terminated into new main fuse cutout.
  • SSE (team 2) turn up later in the afternoon to install new 3 phase meter and do final connections between main fuse and main switch. The engineer incorrectly terminated into the main switch and has connected L1-N, L2-L1, L3-L2, N-L3. Main switch was turned on by SSE energising the DB's.
  • The main DB had a supply to a compressor which turned on and then tripped the circuit breaker after approx 30s which after a phone call prompted the engineer to realise his mistake and come back to correct it. The compressor was tested after and does appear to be working ok but unsure of any unseen damage.
  • The 2nd single phase DB was energised with a PC, monitor, fridge and shutter, lighting all connected. Everything seems to be fine except the roller shutter motor (single phase) that now does not work at all. Again unsure of any unseen damage with the DB, cables or other equipment. The system was energised for 3-4 hours before the fault was noticed.
  • A senior engineer visited site this evening after we reported the issue. They were only there to verify the connections were now correct and did not want to engage in any conversation on the consequences of the initial error.

See pic attached that I took of the incorrect termination for reference.

So where I am looking for some guidance is on what potential issues could have been created by the error that may have damaged the installation. Our electrician can not return until next Thursday (8 days away) and whilst we will be speaking to SSE we dont want to be fobbed off!

Any help would be greatly appreciated.

Thanks

ChristempImageJuwVCi.png
 
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Any single phase loads on L1 and L2 have had 400v put across them. L3 had the correct voltage of 230v except it would have reverse polarity. The compressor which I assume is three phase only had two phases connected with the other connected to neutral.
 
The numpty meter fitter has probably followed the sequence from the meter L1(to Left),L2,L3 then N to the far right (Which is probably what they have been trained to do ) without considering the consequences of of what is already connected.
 
It’s fecking colour coded! How on earth did he mess that up?

I would start the argument now with SSE that what was done has possibly damaged equipment, and will they cover the costs of repair?

You have the evidence right there.


Although…. Should it have been tested by your electrician before being energised?
 
This needs a complaint letter, (i.e. put it in in writing) enclosing the evidence, and a list of all single phase equipment that received 400v with replacement / new value, plus any extra costs incurred.

It's really important to stress that SSE energised the consumer side of this. That shouldn't have happened without some basic testing at the incomer which would have quickly shown up this issue to anyone with any knowledge at all.
 
Had similar to this years ago when a SWEB "engineer" pulled the neutral from the meter of a split phase supply while it was in (imbalanced) use.
I turned up, by coincidence, just after the event , found the "engineer" and his mates standing in darkness, without having a clue of the consequences of what they had just done. I couldn't get any sense out of them as to why they had decided to disconnect the neutral, and soon gave up trying to explain to them what had happened.
I was so incensed by this incompetence that I decided to handle the claim for the customer (mainly domestic electronics) for free, and spent many months with letters going to and fro before getting a settlement cheque. This cheque was " ex gratia" and "without prejudice" , with SWEB at no time admitting any liability.
 
Thanks for all your replies!

We managed to get the electrician over today to assess the fallout.

As westward10 assessed the electrician has confirmed that everything on the single phase supplies run off L1 and L2 has been fried. Roller shutter motor, fire alarm and intruder alarm. He found fuses in the fire alarm and intruder alarm which had blown and these have been replaced and now appear to be functional but are awaiting full testing by the relevant engineers. Roller shutter motor is definitely dead.

Thankfully the single phase DB was supplied by L3 so all appears ok, but I am unsure how the reverse polarity may have affected things?

All bar one new circuit in the DB were installed years ago with test certificate so not sure if it would be the electricians responsibility re-test with the 3-phase connection and prior to re-energising? He did leave us with one 3 Phase outlet 2nd fixed (compressor) as we wanted it running straight away. Either way the SSE engineer left with the main switch energised. We did not get any paperwork so unsure if any testing took place.

We will write to them with a detailed list of items connected as suggested just in case of any further issues but hopefully it is just the shutter motor to replace and they don't give us too much of a fight!

Will keep you updated..
 
I came across this a few years back & it cost the engineer responsible his job, this is a major oversight for sure, not surprised some single phase items no longer work, especially if they were connected across 400volt (2 phases) , I would definately take this further & if the senior engineer has tried to ignore or make light of the situation he his negligent to the extreme. I would 100% take this further.
 
I worked for this company and can tell you we were never allowed to connect tails on the outgoing side of the isolator.This was the job for customers electrian. Something don't add up see it's been sealed up on the incoming. Obviously talking about new connections.
 
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You have the evidence right there.
The only evidence is that there is a picture of incorrect wiring from the isolator, not who did it.
It looks more likely to me that it's not the fault of the meter/isolator installer.

I would also find it unlikely even if they did connect the DBs tails that they would actually energise the isolator along with the DB.
Although…. Should it have been tested by your electrician before being energised?
Exactly.
 
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My guess. Engineer arsed up the tails on the incomer of the isolator as can be seen. Then local site electrician closed the isolator for shits and pickles. And voila. 400v AC travelled near the speed of light towards the shutter motor with a mild hum and sizzling. Mmm bacon.
 
My guess. Engineer arsed up the tails on the incomer of the isolator as can be seen. Then local site electrician closed the isolator for shits and pickles. And voila. 400v AC travelled near the speed of light towards the shutter motor with a mild hum and sizzling. Mmm bacon.
There is nothing wrong with the incomer to the isolator, it's the outgoing that's connected wrongly.
 
I was trying to work that out, I'm only familiar with the Wylex version which has the neutral pole on the left, I couldn't find information on the lewden one pictured.
I just looked at the sequence from the cut-out and then via meter having all the phases on the left.
 
Not really an excuse, whichever is 'wrong'. It's not as if the neutral tail has a grey outer sheath.
You can clearly see that the ingoing to the isolator follows the sequence out of the cut-out in and out of the meter and into the isolator, which has been sealed.

It's unlikely that the meter installer connected to the Db as already said #10
stating that they weren't allowed to make a connection after the isolator.


The likelihood is in my opinion is that it wasn't the meter installer that connected the outgoing side of the isolator and got it wrong.

The tails to the Db would have been connected last and more than likely done by the electrician.
 
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I just looked at the sequence from the cut-out and then via meter having all the phases on the left.

That won't necessarily be the correct order for the isolator though, as I said above the Wylex version has the neutral on the left.
A TP&N switch should have a designated neutral pole which is early make/late break.
 
That won't necessarily be the correct order for the isolator though, as I said above the Wylex version has the neutral on the left.
A TP&N switch should have a designated neutral pole which is early make/late break.
I did think about that, but the Lewden doesn't seem to have an N early make break although some of the rotary ones do.

But in saying that, you still wouldn't expect someone to connect wrongly even if there was a dedicated N switch.
 
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