2 electric showers and melted live wire from relay

[Jberry]

If it were me I would be condemning the whole thing until a thorough eicr inspection was carried out on the entire installation.

But 99% of landlords I know won’t pay for a proper eicr to be done and will just get bodge it a scarper round to ‘fix’ the problem

I'm waiting on the landlords reply. I have told him I want it investigated and someone registered who can provide a cert for the work

 

[Spoon]

So, what power rating are your showers?

 

[SparkyChick]

So, what power rating are your showers?

Post 12:- 2 electric showers and melted live wire from relay - https://www.electriciansforums.co.uk/threads/2-electric-showers-and-melted-live-wire-from-relay.173190/#post-1524259

8.5 and 9 kW I believe

 

[TJ Anderson]

How do you know that?
That’s how it’s supposed to be but look at the state of it

It's a shower priority unit. It will only one run at a time with one taking priority over the other. Terribly installed though!!

 

[Jberry]

So, what power rating are your showers?

9kw & 8.5kw

 

[Jberry]

It's a shower priority unit. It will only one run at a time with one taking priority over the other. Terribly installed though!!

It was basically smoking while my son was in the shower. We had to turn it off as nothing tripped

 

[ChrisElectrical88]

Thats a right lash up. Recently used a shower priority unit, same one as yours, made in ireland. I however moved all the guts into a metal housing. There a great concept, the switchgear is average.

 

[TJ Anderson]

.

 

[TJ Anderson]

ABB Switchgear is very good.

All that needs is a 230v coil, n/o contactor rated 40A or above. They come with 4 pole but only use 2. It's suitably protected against overload by the 40A MCB. That has overheated either due to contactor failing or poor termination. Just get the contactor and damaged wiring replaced.

 

[SparkyChick]

It was basically smoking while my son was in the shower. We had to turn it off as nothing tripped

The smoking will have been caused by the overheating of the conductor and the consequential burning of the plastic insulation (most likely due to a poor termination). It's unlikely any of the protective devices would trip because electrically the only fault appears to have been a bad termination, there doesn't appear to have been any unwanted connections say between live and neutral or earth which would cause the devices to trip.

Basically it looks like a simple case of bad workmanship when it was installed, but as I said, definitely not the first time this has happened.

As for you wanting to see paperwork from the electrical contractor (I use the term loosely based on what you've said), you're not the person ordering the work so technically you've got no right to see the paperwork.

 

[Jberry]

ABB Switchgear is very good.

All that needs is a 230v coil, n/o contactor rated 40A or above. They come with 4 pole but only use 2. It's suitably protected against overload by the 40A MCB. That has overheated either due to contactor failing or poor termination. Just get the contactor and damaged wiring replaced.

Any reason why the power never cut to it?

 

[Jberry]

ABB Switchgear is very good.

All that needs is a 230v coil, n/o contactor rated 40A or above. They come with 4 pole but only use 2. It's suitably protected against overload by the 40A MCB. That has overheated either due to contactor failing or poor termination. Just get the contactor and damaged wiring replaced.

Any reason why the power never cut to it?

The smoking will have been caused by the overheating of the conductor and the consequential burning of the plastic insulation (most likely due to a poor termination). It's unlikely any of the protective devices would trip because electrically the only fault appears to have been a bad termination, there doesn't appear to have been any unwanted connections say between live and neutral or earth which would cause the devices to trip.

Basically it looks like a simple case of bad workmanship when it was installed, but as I said, definitely not the first time this has happened.

As for you wanting to see paperwork from the electrical contractor (I use the term loosely based on what you've said), you're not the person ordering the work so technically you've got no right to see the paperwork.

Thanks for the detailed answer. As for paperwork I really just want to make sure that he doesn't send over someone who has no electrical expertise at all. As he has already done. He sent over someone I knew well and so knew they didnt have the knowledge

 

[Spoon]

Post 12:- 2 electric showers and melted live wire from relay - https://www.electriciansforums.co.uk/threads/2-electric-showers-and-melted-live-wire-from-relay.173190/#post-1524259

8.5 and 9 kW I believe

Ta @SparkyChick . I didn't read inside the quote as I thought the post was an accident, with nothing attached.

 

[Charlie_]

It's a shower priority unit. It will only one run at a time with one taking priority over the other. Terribly installed though!!

Yes I know, I was trying to imply that because of all the badging it may well not be operating as it was designed to

 

[telectrix]

might be an idea to get your local council H&S involved. if i saw that "in the flesh", I'd condemn the lot.

 

[Wilko]

Any reason why the power never cut to it?

Hi - the 40A MCB is designed to not trip at 40A, it's ok with that load. Your 9.5kW shower will draw approx 9500/240 = 40A . So unless both showers went on at once (or some other fault) the MCB will run happily. That contactor is rated at 40A so it should be ok, but it is on its rated max and they do have an operational life limit. From the pics ( ) I suspect a poor termination has caused the overheating, as per @SparkyChick.

 

[MJPD29]

It looks like he fitted that board himself it is brutal

 

[brianmoooore]

If it's a four pole relay, I'd have linked the poles two and two from the start.

 

[Spoon]

If it's a four pole relay, I'd have linked the poles two and two from the start.

It's 3 N/O and 1 N/c

 

[brianmoooore]

It's 3 N/O and 1 N/c

Doesn't look like it by the schematic printed on the front of the relay,but it could be a lower rated contact, intended for latching the relay 'on' in some applications. Obviously check before paralleling them up.