Buzzing noise from mains fuse box

LordGozer

Member
T6 Pro
Hi all

We have been away in our van conversion a few times now and each time have been kept awake by a loud buzzing coming from the mains fuse box in the wardrobe. It starts buzzing when there must be load being drawn from from the battery as you can hear the fridge switching on followed by this noise. Even switching on a led light will cause the buzzing.

Does anyone know what this may be please, it's incredibly annoying. So much so that I may not hook up the the mains at night.

Thanks
 
Are you talking about a mains 240volt fusebox ?
If so I would definitely get it checked out, I don't want to sound to drastic but worst case it could be a loose cable/bad connection that's sparking or arcing inside the fusebox which is potentially dangerous as can cause excess heat
Best case you have some form of rcd or rcbo in there and it's the device itself causing a buzzing which is not right but not unheard off, this wild still need to be changed as is not right

I am a sparky by trade and I find the most common issue like this we come across in houses is when the copper busbar that connects all the fuses together at the bottom is installed incorrectly by either not tightening the screws or inserting the 'prong' part of the bar behind the catch that tightens up on the bottom of the mcb/rcd causing a bad connection
If your confident with a screwdriver you could try disconnecting the electric in your motor and removing the cover of your fusebox and go through all the fuses/screws in turn and check they are all tightened up but either way I would recommend getting it checked by a pro

If you have any pics post a snap of your fusebox
 
Thanks @Pauly very much appreciated. I'm certainly not confident poking around in there, its newly converted so it's back the converters, unfortunately this will be the second time back to rectify issues. 7 hour round trip though.

Will give them a call first though.

Thanks again for the advise, this forum is amazing.
 
My comments are speculation as without seeing it cant be sure but just wanted to make the point its best getting it checked over but i would feel bad if you made that trip only to be told nothing was wrong !!
 
@Pauly the converter thinks it is the charger buzzing and are sending me a new one to fit myself to save me the 7 hour round trip.

Hopefully this will fix it
 
I will do. We are off to Scotland in a few weeks so hopefully the charger will sort it. Having said that we will be driving most days, doing the NC500, so probably won't need an electric hookup, should be able to rely on the leisure battery.
 
We get a slight buzz from our battery charger - only really notice it when first on hook up after being sat in the drive for a while though. Assuming that your fridge runs from the 12v circuit, it makes sense that you notice it after the fridge compressor kicks in, i.e. battery drop by fridge so charger kicks in to top up.
 
Many but not all electronic circuits that change voltage levels will include a transformer. This basically is two coils of wire wound around a laminated core. To work they require the supply to be alternating like the mains does. if the laminations come loose then the alternating magnetic field causes them to buzz at the frequency of the supply, usually 50 hz ( mains frequency). It's not normally an issue if it's not too loud but it will not get better and if it does get loud then it will get warm. If its new and it buzzes get the supplier to exchange it. Like anything these day's there are cheap transformers and quality ones. Science lesson over.
 
Update

Replaced the charger, easy job to do once I managed to get to it, hidden behind a panel in the cupboard below the gas hob.

Much less noisy than the old one but still a definite buzzing coming from it. Will see what happens over the next few weeks whilst on holiday as its really only noticeable at night, daytime noise drowns it out.
 
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