Ask an Electrician anything...

[silentbrown]

Thanks. It's TN-C-S

It seems a jump from "socket outlets <32A which are used to supply mobile outdoor equipment" to "possibility of sockets being used to supply external to house".

It's "possible" to use upstairs sockets (or even light fittings!) to supply outdoor equipment. I've seen that done in the past

The CU is a 25yr old MK Sentry. I *think* you can get RCBO's to fit, rather than replacing the entire board. Not sure at what point that becomes sensible?

[ruggedscotty]

silentbrown said:

Thanks. It's TN-C-S

It seems a jump from "socket outlets <32A which are used to supply mobile outdoor equipment" to "possibility of sockets being used to supply external to house".

It's "possible" to use upstairs sockets (or even light fittings!) to supply outdoor equipment. I've seen that done in the past

The CU is a 25yr old MK Sentry. I *think* you can get RCBO's to fit, rather than replacing the entire board. Not sure at what point that becomes sensible?

18th edition requirements for electrical installations - its the interpretation of the regs. And the view of the electrician doing it.

sensible ? Oh you do know that goes out the window.... along with the extension lead ;-)

[dhutch]

silentbrown said:

The CU is a 25yr old MK Sentry. I *think* you can get RCBO's to fit, rather than replacing the entire board. Not sure at what point that becomes sensible?

I guess it depends on your views on life, times, and the risks.

For my certainly if you have any children who might visit with curious fingers, a dog which likes to chew, etc, it's an absolute no brainer even for the cost of a new board which even with fitting it's going to be that much.

Presumably it's a split load board and they ran out of RDC ways and bodged it, maybe the unprotected ring main became so when they put the extensions ring it in its place.

If it's a small or low draw ring, maybe you could merge it with an existing protected ring. Maybe you can get a longer bus bar for the RCD side?

[ruggedscotty]

dhutch said:

silentbrown said:

The CU is a 25yr old MK Sentry. I *think* you can get RCBO's to fit, rather than replacing the entire board. Not sure at what point that becomes sensible?

I guess it depends on your views on life, times, and the risks.

For my certainly if you have any children who might visit with curious fingers, a dog which likes to chew, etc, it's an absolute no brainer even for the cost of a new board which even with fitting it's going to be that much.

Presumably it's a split load board and they ran out of RDC ways and bodged it, maybe the unprotected ring main became so when they put the extensions ring it in its place.

If it's a small or low draw ring, maybe you could merge it with an existing protected ring. Maybe you can get a longer bus bar for the RCD side?

Ive swapped the bus before and made the protected a non protected and then everything else went through the protected side. depends on what you have and how you can botch it.

I know its easy to say but id be looking at getting the board done, a new board and then see about upgrading the rest as you go along if you can. be sure to have some extra ways left for expansion. Also going down the individual rcbo route is a huge improvement in terms of reducing the effect of a trip.

[silentbrown]

ruggedscotty said:

I know its easy to say but id be looking at getting the board done, a new board and then see about upgrading the rest as you go along if you can. be sure to have some extra ways left for expansion. Also going down the individual rcbo route is a huge improvement in terms of reducing the effect of a trip.

Thanks all - That's what we're doing. RCBOs are available (at a price!) for the old board, but soon realized it was false economy to just add a couple of those.

[Belle427]

Just wondered how domestic sparks find a nuisance tripping rcd.
Not IR tested the circuit yet but my downstairs sockets trip the rcbo randomly maybe every few weeks but there is no real pattern, I’m convinced it’s when a few appliances are on.
Rcbo is new.
An earth leakage clamp meter may be the best option for this?

[Get Karter]

Quick safety Q

Noticing a plasticky odour (like a laminator if you know what I mean) in my porch where the fuse box is located. Do I need to switch off at the breaker immediately?

Thanks

Ps. No other signs of problems. No flickering, no singe marks etc

[dhutch]

Get Karter said:

Quick safety Q

Noticing a plasticky odour (like a laminator if you know what I mean) in my porch where the fuse box is located. Do I need to switch off at the breaker immediately?

Thanks

Ps. No other signs of problems. No flickering, no singe marks etc

Doesn't sound ideal.

Can you feel if one of the breakers is warm? Is it a one off, or persistent? How flammable is your porch! Consumer unit fires are rare but not unheard of.

[Get Karter]

dhutch said:

Doesn't sound ideal.

Can you feel if one of the breakers is warm? Is it a one off, or persistent? How flammable is your porch! Consumer unit fires are rare but not unheard of.

Thanks for the response. Breakers are all cool. Smell is persistent but not increasing. Going to get an electrician to check it over today.

[Get Karter]

Get Karter said:

Thanks for the response. Breakers are all cool. Smell is persistent but not increasing. Going to get an electrician to check it over today.

Turns out the neutral going into our secondary box (put in for extension work on our kitchen 5 years ago) wasn’t securely connected and had been melting the blue plastic at the loose end.

[dhutch]

Get Karter said:

Turns out the neutral going into our secondary box (put in for extension work on our kitchen 5 years ago) wasn’t securely connected and had been melting the blue plastic at the loose end.

Lovely. Good spot!

[Gary C]

RS, here's one for you

I work for a museum thats suffering from some vintage equipment failure.

As its in a large victorian mill, with many uses and a carpet manfacturing shop, I wonder if I am getting mains borne surge/spikes that could be damaging things.

I can't get my hands on a fluke 1773 or similar and wondered if there are any consumer unit mounted mains filters that we could use ?

I suppose what we really need is an isolating 1:1 transformer but thats probably going too far

Wondered if anyone has come across similar ?

[ruggedscotty]

Gary C said:

RS, here's one for you

I work for a museum thats suffering from some vintage equipment failure.

As its in a large victorian mill, with many uses and a carpet manfacturing shop, I wonder if I am getting mains borne surge/spikes that could be damaging things.

I can't get my hands on a fluke 1773 or similar and wondered if there are any consumer unit mounted mains filters that we could use ?

I suppose what we really need is an isolating 1:1 transformer but thats probably going too far

Wondered if anyone has come across similar ?

Oh the fluke analyser would be the way to do it...

What sort of power is being taked about here, what are you trying to support, and dioes it have high start up currents etc... If it is mains borne then the consumer unit surge protection could have a part to play. However.... What if the surges are originating from the equipment in the museum. That would be interesting.

Could the equipment be operated from DC ? I know thats a bit of a biggie as it would take some doing to change out your switches to dc from ac. but it has had benefits in the past at reducing harmonics and surges in some places.

back to distribution units and surge protection. This protects the installation from external surges going to the installation. However you could fit these at various places in and around to try and iron out the surges if originating within the installation.

https://www.tlc-direct.co.uk/Products/CGSRG1VCU.ht...

https://www.amazon.co.uk/dp/B0B945MDQ8/ref=sspa_dk...

https://www.electricaldirect.co.uk/browse/consumer...

https://cauk.tv/articles/power-quality-issues-tran...

[SEDon]

Kitchen extension done in 2019, there are 3 sets of lights on a 3 gang swich. 8 spots in upper kitchen, 2 pendants and 4 spots in the lower kitchen. For context work was carried out by reputable firm and done neatly. For 3 years we had no issues then the 3rd set of lights started tripping the RCD. Initially this happened after a while >30 mins of being on but then quickly started happening instantly once the switch flicked. Checked for leaks, insulation, all wiring I could, changed all the bulbs, tried a new switch but no luck. Then I tried removing lamp holder in the last spot and it seemed to fix it so i replaced it for a new one and for the last year had no issues. Then the other week it started happening again. After disconnecting the last two lamp holders it stayed on for 30 mins before tripping again. Currently removed the 2nd one leaving just the one spot on and for now it's working.

Any idea what is likely the issue here?

[AW10]

Presumably the spots are LEDs? Have a close look at each of the drivers looking for hot spots.

[SEDon]

AW10 said:

Presumably the spots are LEDs? Have a close look at each of the drivers looking for hot spots.

Sorry should have said, they are mains GU10. The lone bulb has just tripped it

[Gary C]

ruggedscotty said:

Gary C said:

RS, here's one for you

I work for a museum thats suffering from some vintage equipment failure.

As its in a large victorian mill, with many uses and a carpet manfacturing shop, I wonder if I am getting mains borne surge/spikes that could be damaging things.

I can't get my hands on a fluke 1773 or similar and wondered if there are any consumer unit mounted mains filters that we could use ?

I suppose what we really need is an isolating 1:1 transformer but thats probably going too far

Wondered if anyone has come across similar ?

Oh the fluke analyser would be the way to do it...

What sort of power is being taked about here, what are you trying to support, and dioes it have high start up currents etc... If it is mains borne then the consumer unit surge protection could have a part to play. However.... What if the surges are originating from the equipment in the museum. That would be interesting.

Could the equipment be operated from DC ? I know thats a bit of a biggie as it would take some doing to change out your switches to dc from ac. but it has had benefits in the past at reducing harmonics and surges in some places.

back to distribution units and surge protection. This protects the installation from external surges going to the installation. However you could fit these at various places in and around to try and iron out the surges if originating within the installation.

https://www.tlc-direct.co.uk/Products/CGSRG1VCU.ht...

https://www.amazon.co.uk/dp/B0B945MDQ8/ref=sspa_dk...

https://www.electricaldirect.co.uk/browse/consumer...

https://cauk.tv/articles/power-quality-issues-tran...

We have four 32A ring mains and run quite a few (read far too many) machines off one ring and given their vintage nature (40 years old some of them) earth leakage can be a little suspect.

However there real issue is machines failing and I'm wondering if mains borne spikes are pushing some vintage chips over the edge.

Thanks for the info

A SY2-D sounds Ideal. Wiring, it looks as if you install it on a DIN rail through its own B32 CB and it then protects all circuits on that CU ?

https://www.surgedevices.co.uk/wp-content/uploads/...

Edited by Gary C on Monday 20th March 20:00

[ruggedscotty]

Final sub-circuits and sensitive electronic equipment eg. Fire/Burglar alarm panels and PLC’s which are fitted more than 10 metres from the last surge arrester should have a Type 3 surge arrester fitted at the panel or equipment to be protected.

So Id be doing the DB as a seperate entity and then a surge device incorporated at each unit.

Its over kill I know but with your case you have a lot of antique devices....

I wonder if it would be worth doing your own earth electrode, and keeping that seperate for your protected equipment.

If the current draw isnt too much could you seperate and run the equipment off an isolated supply ? When in Bosnia we did this with a listening unit that was always having issues with the line interference.

1:1 isoaltion tramsformer and a locally derived TN-S distribution for your dedicated kit.

[dhutch]

SEDon said:

AW10 said:

Presumably the spots are LEDs? Have a close look at each of the drivers looking for hot spots.

Sorry should have said, they are mains GU10. The lone bulb has just tripped it

LED? With integral driver? Glass case or aluminium. I would say the bulb is fairly and putting a voltage to earth.

[dhutch]

Gary C said:

We have four 32A ring mains and run quite a few (read far too many) machines off one ring and given their vintage nature (40 years old some of them) earth leakage can be a little suspect.

However there real issue is machines failing and I'm wondering if mains borne spikes are pushing some vintage chips over the edge.

Thanks for the info

A SY2-D sounds Ideal. Wiring, it looks as if you install it on a DIN rail through its own B32 CB and it then protects all circuits on that CU ?

https://www.surgedevices.co.uk/wp-content/uploads/...

Or failing due to age? But understand giving them the best protection you can is key too.

What sort of machine are they, you say chips so obviously some electronics? Motor? Power draw?