Rcd size for caravan

[Bobikleeds]

Hello all.
I have a question about rsd size. I’ve had a fault with my old rcd last weekend in wales. Basically one of the positive wires was loose and the rcd has melted a bit together with the wire attached. Now the old rcd was 25amp. I went to the local screwfix but they didn’t have any 25 amp ones so I’ve bought the smallest they’ve had which is 40amps. It works fine now but can i leave it or should i buy 25amp one?
Thanks

 

[otherclive]

You should source a 25 amp. Just like fuses putting in a larger one potentially risks your circuit.

 

[Bobikleeds]

Will do. Thanks for the quick response

 

[VicMallows]

Disagree. If it is simply an RCD (and probably also serving as the main incoming isolator) then it is not an overcurrent device. It will have a rated tripping current (usually 30mA) and a maximum load rating. A higher load rating will make no difference.

 

[Dodger524]

Disagree. If it is simply an RCD (and probably also serving as the main incoming isolator) then it is not an overcurrent device. It will have a rated tripping current (usually 30mA) and a maximum load rating. A higher load rating will make no difference.

I agree with Vic. It's the mA rating that is important and 30mA is the correct rating.

 

[ProfJohnL]

Totally agree with Vic and dodger, the over current protection is provided by the MCB's not the RCD. The RCD is a disconnection device, and provided its burden current rating is not less than incoming supply (16A for caravans) and its tripping current is 30mA then it should be fine.

In point of fact its likely the replacement RCD purchased from Screwfix may be a better quality unit so stick with it .

 

[Bobikleeds]

Thank You all guys. Very helpfull. Cheers