Whining Sound From an MCB

[GEC]

Can anyone explain the noise coming from my consumer unit each time i start my tumble dryer.
It is connected to my kitchen ring main and starts the MCB whining when running. I have added an extension lead and connected it to different ring mains, this is the 3rd tumble dryer, changed the MCB, moved it from one RCD to the other RCD and four electricians have called and failed to resolve it without success.

HELP its driving me mad!!!

 

[telectrix]

what's the MCB rating?

 

[Pete999]

Can anyone explain the noise coming from my consumer unit each time i start my tumble dryer.
It is connected to my kitchen ring main and starts the MCB whining when running. I have added an extension lead and connected it to different ring mains, this is the 3rd tumble dryer, changed the MCB, moved it from one RCD to the other RCD and four electricians have called and failed to resolve it without success.

HELP its driving me mad!!!

Did any of the"Electricians" bother to check what current the "ring main" is drawing?

 

[telectrix]

could be busy drawing a sketch for monty python. too busy for mundane things like tumble dryers.

 

[GEC]

Its a 32Amp MCB and there are 6 double sockets on that ring. As I have said though I have attached the Tumble dryer to other ring mains in the house with an extension lead and that MCB starts making the noise then???

 

[driverman]

Have the electricians checked that ALL connections within the consumer are tight including the bus bar? DO NOT do this yourself. Electrician required.

 

[GEC]

Yes, all has been checked and even replaced the MCB.

 

[Marvo]

Either the load is very close to the rating of the circuit breaker or it could be some kind of PWM circuit like a motor speed controller that's causing it. Sometimes the switching frequency of the triac/diac can cause resonance of the mag circuit in the MCB, it's something that's also caused by other phase control devices like lighting dimmers occasionally. If the electricians have tested the circuit and checked the terminations on the neutral bar and the circuit breaker etc then it's not something I'd worry about.

If it's an annoyance you could try replacing the tumble dryer socket with an EMI filtered type. Usually they're used to protect the appliance against noise and spikes but it would also work the other way around in this case and prevent the appliance introducing noise back into the supply. I'm not guaranteeing this will work but it might be worth a try in the absence of other suggestions and I'd suggest using a trusted name-brand item, not a cheapie off EBay.

 

[GEC]

thanks for that, Its much appreciated and I will pass the information on to an electrician.

 

[telectrix]

try plugging the dryer into a surge protected extension lead.

 

[Marvo]

Good call Tel, this would work the same as a surge/EMI protected wall socket but it would be easier for an unskilled person to try themselves. Again I'd recommend buying a decent one from a recognised manufacturer, the quality of these surge protection devices and EMI filters varies greatly between the cheap nasties and the good ones. The extension lead type should be available from most decent computer shops but double check it's rated to 13Amps, some of them have a little built-in circuit breaker that's rated at 5 or 10 Amps which probably won't be high enough for a tumble dryer.

 

[Darkwood]

I had a lot of whining when I use the washer but she has to learn her place is in the kitchen!

 

[GEC]

Yes, that would save me another visit from sparky no4. I have checked the load on the circuit and there is a toaster 1000w, kettle 3000w, microwave 900w, washing machine 600w, tumble dryer 2800w and a fridge freezer which i don't know the rating of. I would have thought that this is typical of a kitchen?

 

[Marvo]

Wow, that's quite a load but I assume you don't run more than one or two of the items together at any given time.

Does the circuit breaker make the whining noise if you just run the tumble dryer without any of the other appliances?

 

[telectrix]

does it want feeding or walkies. that's usually the case in our place. oops. that's the dogs.