Wrong on so many levels.
Ok, it’s Schneider so it isn’t the cheapest of the cheap from Screwfix but look at how little care and attention has been dedicated to the installation.
The incoming tails look like they are under strain.
Cables have been poorly dressed and terminated, incorrectly labelled with earth tape used on the neutral conductor which had an inner insulation of brown and not blue.
Aesthetics – not against regulation but the installer not made any effort to dress the cabling.
Why, you ask?
Because he’s been in a rush to get the job done quickly and has thrown in it.
The neutral cables have been extended as the neutral bar is at the sides. Not much can be done about this (other than selecting a consumer unit where it is at the top, or using RCBOs instead?) but the way they’ve been joined using connector blocks is far from ideal.
Best practice would be to use insulated crimps which wouldn’t need taping.
Now I mentioned this has been thrown in.
I only got to see this consumer unit as the homeowner emailed saying he could hear a humming sound coming from within and he wanted it checking out for peace of mind.
On arrival I heard a worrying arcing sound within seconds of being within earshot.
I took the cover off and tested the incoming supply tails – as soon as I placed my leads on the terminals there was a momentary loss of power to the installation (the house lights flickered) and the noise increased.
The customer had a smart meter fitted but no double pole isolator – so whilst I believed we had a potential connection issue and/or a burnt main switch. I was unable to prove it until we isolated the incoming supply in the metering cupboard.
I advised the homeowner of my findings and explained we need either UKPN or his Metering company (Eon) to attend and install a double pole isolator.
Calls were made and Eon attended the next day to install a double pole isolator at a cost of £120.
I attended a second time, isolated the incoming supply and inspected the main switch.
What I found
Obvious signs of thermal damage from excessive heat generation with poor termination the likely cause.
A burnt main switch terminal on the load side.
Whilst the main tails entering the supply side (top) of the main switch were under excessive tension it was the load side that appeared to be the problem.
I’m confident the cause was a loose connection on the neutral terminal.
This caused burning of the main switch, the busbar that links the main switch to the neutral bar as well as causing damage to the neutral tails on the supply side.
The decolourisation is a result of electrolytic action, it’s typically found on shower pull cords that haven’t been tightened properly on the shower stops working.
All due to rushing and not checking the connections.
The upside is that whilst this could have resulted in a fire, the homeowner had the common sense to seek an expert as soon as he realised there was a problem and we got it resolved.
This fault lay undetected for so long because the home didn’t have any high powered items such as Electric shower or an EV charger – pulling 32 amps for up to 8 hours throughout the night would have exacerbated this issue very quickly.
I suspect had EV charger been connected the outcome would have been severely different.
I replaced the main switch, cleaned the neutral busbar, re-terminated the incoming tails and had the supply re-energised.
I performed further tests inside and outside the board and left the customer to enjoy his evening after 2 days of worry and fear.
The homeowner trusted this electrician who was referred by a friend… he wasn’t a price shopper and certainly didn’t seek a low-cost job which makes this rather unfortunate.
Someone who actively looks for the cheapest price gets what they deserve but that wasn’t the case here.
Cost of 3 visits, parts, labour and VAT circa £320.
Loss of appliances for 1 night – nuisance.
The worry of a fire starting as you sleep – great, if you like insomnia.
If it wasn’t clear already, going cheap aint a good idea.
Pay cheap pay twice.
Get a qualified electrician out, don’t just ask neighbours or friends – do your own due diligence and it’ll pay dividends.
It’s your home after all.
