Tripping Shower

[Crannoid]

I have a 9.5kw shower running from a 40 amp rcb. About 10 minutes after turning the shower off the rcb trips. This has only just started, the shower has been in since we moved in. There is no pull cord switch, or rocker switch for the shower.
Any thoughts why this might be happening?

 

[James]

yes,
9.5kw at 230V is 41.3A
it is only a slight overload but will eventually trip the rcd.
they might have got away with it whilst it was new and all the springs in the breaker were at there peak performance.

have a look at the instructions for the shower and see what supply requirements are.
I suspect it is an under rated supply.

 

[DPG]

To clarify, it's an MCB tripping, rather than an RCD?

 

[Spoon]

Welcome to the forum mate.
As above, are you sure it's the RCD tripping and not the MCB?
The RCD tripping would imply a fault with shower or cable to the shower. Maybe some water is leaking into the shower....
I can't imagine a MCB tripping after the shower has been switched off for 10 mins from an overload point of view... Again water ingress into the shower may cause this.

 

[Taylortwocities]

Post a photo of the device that trips.

 

[Crannoid]

Hi,
Thanks for all the replies so far.

Sorry for the confusion over RCB or MCB.

Here is a photo of the offending device

 

[telectrix]

my first thought would be that the MCB has been running at it's limit for so long, it's just got fatigued. get a local spark to replace with a 45A cartridge fuse. ( unless he can source a 45A MCB.).

 

[freddo]

CGD/Lewden stuff only has MCB and RCBO current ratings of 40 or 50Amps, no 45Amp.

Very strange it trips after 10 minutes of being off. I'd be visually checking inside the shower for leaks or burnt stuff first.