Speak EV - Electric Car Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
99 Posts
Discussion Starter #1
A number of months back, as part of the Renault Zoe deal, I had a Chargemaster Homecharger installed. Rather than an earthing rod they use some electronic device (can't remember what they call it) which sits next to the fuse box. This hums and having chased up on this both with Chargemaster and an install engineer (my external unit had to be replaced as the SIM component in it failed) this is normal. It's also just on the border of where I pick it up. I know in theory over time I will learn to ignore it, but I wonder if anyone else here has been in the same situation and how they got round it.

I'm contemplating buying these from Amazon to line the inside house facing surfaces on the fuse cupboard (there are a good half dozen different 'brands' for the same thing). Thoughts? Note I beleive cone/shape foam will not work as they are about reducing noise in the room you are in, not outside.
 

·
Registered
Joined
·
4,913 Posts
If you are reasonably competent then I'd try this: Turn the power off, open the offending box (assuming the fixing screws are inside), loosen the screws, push a little rubber in between box and wall near each screw, and then just nip them back up so the box is held securely but there is a little give.
In fact you may find just backing the screws off a 1/4 turn makes a difference.
 

·
Registered
Joined
·
1,221 Posts
Most often the humming is caused by a vibrating transformer or choke. It's not a fault, and damping the sound should be practical, either using that foam or by using rubber spacers if possible.
 

·
Registered
Joined
·
99 Posts
Discussion Starter #4
Cheers - it's an electrical hum - certain it's probably what @tom66 has described though I don't see how you can dampen that and I neither trust myself nor do I think there's space. Here's the offending item:
132535
 

·
Registered
Joined
·
264 Posts
We had the exact same humming noise when ours was installed. Drove me a little mad but then the sound seemed to fade away and stop after a couple of days. We do occasionally get a ‘clonking’ noise as though there’s a switch opening and closing, got used to that now. I assume it’s protecting the mains circuit so it doesn’t overload?
 

·
Registered
Joined
·
99 Posts
Discussion Starter #6
For awareness the rubber sheets have made a difference, you can still hear the hum with the cabinet closed, but it is quieter now and you can't hear it in the next room. As I only used about 4 of the 12 sheets I might try a second layer.
132803
 

·
Registered
Joined
·
4,865 Posts
Cheers - it's an electrical hum - certain it's probably what @tom66 has described though I don't see how you can dampen that and I neither trust myself nor do I think there's space. Here's the offending item:
View attachment 132535
Given that it's DIN mounted there is nothing that you can do about the noise other than try and reduce it with insulation.
I gather that the equivalent Matt:e device is also noisy but to a slightly less extent. Overall not my favourite devices both from a safety and a noise perspective.
Edited to add - the sticker saying "Warranty Void if Broken" is an interesting take - these devices are able to be altered from the factory but must not be user amended in order to stay within the wiring regs. Keep well away from them.
 

·
Registered
Joined
·
308 Posts
Looking at the picture, the most likely source of the noise is the contactor at the end of the rail on the right-hand side. These have a magnetic coil which is powered to hold the contacts closed to provide the supply to the EV charger, it's most likely this that is making the noise.

The next module to the left, the one with the warranty sticker is a voltage monitoring relay, it will have a little electronic power supply so its possible this might make some noise, but generally these are silent or very quiet. Then an MCB which are silent and then an RCBO which are silent.

You can buy silent contactors, Hager make them, but the one fitted is from a low cost manufacturer so will be a basic model.

Not much you can do really, other than trying to stop the noise getting out which is what you've done. If it really is bad/annoying/frustrating you could perhaps see about getting the contactor changed with a silent one.
 

·
Registered
Joined
·
99 Posts
Discussion Starter #9
Cheers @WithEthyl for the explanation - I should save that info away - I'm not an electrical minded person (I can change light bulbs, fuses, wire plugs, but I'd not trust myself much beyond there). Looks like a Hager replacement would be a couple of hundred quid, plus fitting, so not really an option (though might have been if my pet electrician was up for it and the sound deadening had not worked),
 

·
Registered
Joined
·
308 Posts
Not quite that expensive - they're around £55 - £70 on Amazon, but yet plus the fitting and also issues around warranty.
 

·
Registered
Joined
·
4,913 Posts
These have a magnetic coil which is powered to hold the contacts closed to provide the supply to the EV charger, it's most likely this that is making the noise.
Sometimes cycling a noisy contactor off and on will make it quieter - for a while anyway. (But the converse can also happen :oops: )
 

·
Registered
Joined
·
47 Posts
Cheers - it's an electrical hum - certain it's probably what @tom66 has described though I don't see how you can dampen that and I neither trust myself nor do I think there's space. Here's the offending item:
View attachment 132535
I’ve got the exact same setup as this with my BP Chargemaster and also have the loud hum. It’s in my garage though so it’s not really an issue as you can’t hear it in the house.
 

·
Premium Member
Joined
·
11,453 Posts
That is a lot of electrical stuff to supply a charging point. Hopefully Chargemaster are busy designing a point that has more 18th Ed safety kit built into the unit to get costs down and avoid potential noise in the home.

A bit off topic, but the EV-DB scrawled on the lid would not sit well with my OCD! Why can't installers use a label machine to keep things neat and tidy.
 
1 - 13 of 13 Posts
Top