10A RCBO for a lighting circuit...?

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I currently have a 6A standard MCB covering the lights in my 1 flat. I'm getting an extractor putinto the bathroom and the electrician says it will take me over this 6A current and that as the wiring is 1.5mm he can fit a 10A RCBO.

I spoke to my dad and he's sure that you can only use 6A for a lighting circuit, so who's right?
 
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whats the wattage of the fan?

edit..

does your total lighting load on that mcb go over 1380amps? (edit i meant 1380watts)

edit again...

thats 23 60watt light bulbs..!
 
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you can have a 10A for lights.. very common in bigger installs and industrial.. ( providing that the cable is sized accordingly and any de-rating factors have been taken into account.. )
 
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Thanks folks

Re: voting for the electrician, I want to make sure it's done properly and safely, regardless of whether he's liable.

I've ony got a 1 bed flat, but spotlights in most rooms (5 sitting room, 6 kitchen, 2 bathroom, so:
18 spotlights = 900w
3 normal dangley lights (2 entrance, 1 loft) = 300w?
2 extractor fans = ???w

I reckon it's close if not over. The guy fittng it said he thought the fan would take me over, hence rasiing the rating.

So is what hes' done safe and has he used the right RCBO type?
 
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With suitable cabling, the regs. allow lights with standard BC or ES fittings to be put on circuits up to 16A.
 
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The guy fittng it said he thought the fan would take me over, hence rasiing the rating.
He is wrong.
The figures you provided are 1200w without the fans. Most extractors are only 20 watts or so, but even if they were 50 each, the total is only 1300 watts, still less than 6A.

That also assumes that every single light and both fans will all be on at the same time, which is not likely. A 6A MCB won't trip at 6A anyway, it will take significantly more than that for an extended period of time.

A 10A device could be fitted, but it isn't needed.
 
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Although the 17th Edition permits 16A to lighting circuit it also says manufactures recommendations should be followed and in most lighting circuits we use ceiling roses rated at 5/6A as junction boxes so in most cases you can't use more than a 6A device to protect lighting.

Also the BA22d light fittings unless porcelain are normally rated at 2A and it relies on the lamp having an internal fuse built in. With old British tungsten lamps this was normally the case.

However many of the cheap imports of CFU don't have these built in fuses so if they fail short circuit then with greater than 6A (Which is still 3 times the rating of holder) there is a higher chance that the contacts will weld themselves to the holder which means the whole light will need removing before you can re-energise power to lights. Therefore personal I feel it is folly to exceed 6A protective device even if ceiling roses are not used as junction boxes unless all lighting contains built in fuses as would be found with most long tube type florescent lamps.

But the regulations don't directly say you can't use a 10A MCB so I am still wary as says you can't. But would say "I wouldn't."
 
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im guessing you only have 'one' MCB for the lights... not two?

upstairs/downstairs..?
 
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