Existing 5amp switches on 6amp circuits

[Paul P]

Hi This may seem a silly question, I heard a rumer that you can't keep the old 5amp light switches if you replace a consumer unit and fit 6 amp mcb's. I think it is a load of tosh. Does anyone have a definite answer?

 

[hasel5]

O load of tosh mate

 

[Sintra]

The switch is limited to the load that it switches not the load of the circuit. I would say it's a load of tosh.

 

[7029 dave]

Rubbish

 

[Flanders]

As long as the load connected to the light switch is 5 amps or less then I can't see a problem

 

[Plonker 3]

Imagine a 13 amp socket on a 16 amp radial circuit, it's not dissimilar.

 

[Octopus]

Or a 13A socket on a 32A circuit!

 

[Darkwood]

Paul P... exactly where did you hear this rumour?

We have a lot of ears to the ground on here and this is a new one on me although complete rubbish- half the equipment in any installation wouldn't comply if this scenario was correct

 

[Engineer54]

Hi This may seem a silly question, I heard a rumer that you can't keep the old 5amp light switches if you replace a consumer unit and fit 6 amp mcb's. I think it is a load of tosh. Does anyone have a definite answer?

Have you been listening to one of those 17 Day whizz kids by any chance?? lol!!

 

[Sintra]

It's probably another way of scamming the poor customers after they have been convinced to change their perfectly good consumer unit.

 

[old_sparky_RE]

http://www.electriciansforums.co.uk...85039-light-switches-mcbs-size-reg-536-a.html

A question I posted 2weeks ago as we were being inspected and Reg 536 was quoted as the reason for failure!
Overcurrent is fault current or overload current (see430.3), so with this in mind all 5A switches must be fitted with 5A MCB's !!!!!!!!
Common sence is NOT allowed. Do as I say.

 

[Engineer54]

Apart from being a complete load of rubbish, you try finding a 5A MCB!! lol!!

This inspector clearly doesn't understand the basics of what he's inspecting. Did he put anything down in writing by any chance??

Oh and by the way, over current and fault current are completely different and have completely different and separate mechanisms within MCB's (or MCCB's etc) eg thermal & magnetic, for the protection for each type of current.

As for the minimum sized lighting cables, as related too in you're link, this is common practice on larger sized projects, and we too have 2.5mm minimum for lighting circuits, but that is only for ''Fixed or Installation wiring, not factory supplied equipment etc.

If anyone else is sacked because of these idiots, take the company to court for unfair dismissal, ....and then see what happens!! lol!!

 

[pepparz]

ive got loads of 5 A MEM MCBs there type 1 to BS3871 category of duty M6, order code; 51QEB.

 

[Engineer54]

ive got loads of 5 A MEM MCBs there type 1 to BS3871 category of duty M6, order code; 51QEB.

Will they fit a modern CU though?? And come to that, do/will they comply with 17th BS7671?? Those Type 1/ 2/ and 3's must have been out of production for years now....

 

[Kamikaze]

You can still get a load of 3A mcb’s. :smile5:

 

[old_sparky_RE]

In reply to E54

All recorded and 'repaired' with 277v 20A switches c/o US Goverment funds.

I know and understand the difference and functions of an OCPD it's just the 'gate keeper' software we have stops me adding those smiley face things to show when I'm being pedantic !!

US contracts company for DOD (US Goverment), employment contract signed in Dubai, working in/on NATO, Crown and US soil in Afghanistan... likleyhood of winning anything ZERO.

 

[Engineer54]

In reply to E54

All recorded and 'repaired' with 277v 20A switches c/o US Goverment funds.

I know and understand the difference and functions of an OCPD it's just the 'gate keeper' software we have stops me adding those smiley face things to show when I'm being pedantic !!

US contracts company for DOD (US Goverment), employment contract signed in Dubai, working in/on NATO, Crown and US soil in Afghanistan... likleyhood of winning anything ZERO.

You have never mentioned where you are, or what Code or Reg system you are working too. Unless i'm missing something, i'm pretty sure everyone here thinks you're talking about a UK situation. Not sure how you retrofitted American typical 20A toggle switches in a UK back box mind!! lol!!

 

[Flanders]

Imagine a 13 amp socket on a 16 amp radial circuit, it's not dissimilar.

But a 13 amp socket will only have a max load of 13 amps as the fuse in the plug top would protect it,(unless someone has shoved a euro plug in it ) but a light switch does not have any local over load protection so although as I stated, as long as the max demand on the 5 amp light switch does not exceed 5 amps then there is no problem but if the switch is supply a load of 6 amps then it does not comply .

 

[MDJ]

Total Rollocks, the amount of 32 amp Switch fuses bolted onto 200 amp busbar chambers and the cables only 6mm2 is very common, so a 5 amp switch connected to a 6 amp MCB is no problem at all, what a silly thread.

 

[HappyHippyDad]

The switch is limited to the load that it switches not the load of the circuit. I would say it's a load of tosh.

I've thought about this before and thought about asking the forum.. Its not rare to see the switch with a neutral in it which means if its at the beginning of the circuit its taking all the current, not just what its switching?

Or a 13A socket on a 32A circuit!

Also thought about this! :smiley2:

I'd be interested to know how we can use sockets rated as 13A when the current running through them could be as much as 32A? Even though the 32A is unlikely, it's certainly possible to be well over 13A at times. I guess the sockets are able to take much more than 13A, but it seems a bit misleading to rate them as such.