6Amp Mcb Buzzing

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Bluejusty1

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Evening guys, I have a 6 amp Wylex mcb that is buzzing! It is feeding a lighting circuit which has a total of 40 6w spots, 1 pendant and 3 fluorescents in the loft. It's not overloaded. There are 4 rooms with dimmers in, the biggest room has 7 spots, so that's 42w. If I turn two rooms off(dimmers) the buzzing stops! I'm totally lost! I have out a lot more spots on a circuit before and not had a problem! Any help grateful!

 
Explain please duck, it's a new installation, first time I have put led throughout. Dimmers are auroras.

 
Some dimmers do cause MCB's to buzz, if you turn the dimmer up to full brightness it will probable get quieter or go away entirely.

I wouldn't worry too much about it unless is so loud it's a general annoyance. I's probably either due to the high switching frequency of the dimmer output diac causing resonance with the inductive coil in the mag circuit of the MCB or it harmonics possible causing excessive heat on the thermal side circuit. Either way you'd need to replace either the dimmer or the MCB or both with different brands. If you've got the patience to put a scope on the circuit you could make an RC filter but it's a lot of work and messing around for something that's unlikely to have any serious consequences.

 
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I have had buzzing breakers on jobs &  for  13 years in my own house. The buzzing gets louder as the lamps are dimmed. I now have LED lamps in quite a few rooms and its made no difference, am i bothered.... No.

Do a search for my breakers are humming, its been discussed here a few times.

 
What tune are they humming though ? Thats the thing Slapper !

You need to get a 32A for the bass notes :p     I've got a couple of Hager 10 Amps that harmonise just like the Everly Bros :C

 
Sorry Slapper  ...never read the original !!! :C

OK...  I have a whole consumer unit that ...when I dim my lights.. ... bursts into song like a Barbershop Quartet  & the main cut-out  hums along just behind the tempo. . 

 
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