Shower intermittent tripping

[Mab40]

hi

i have a creda 9.5 Kw shower which some time trips and some times does not it is on 10mm2 cable with a DP ceiling switch and a 45a mcb
any suggestions please.

 

[mfarrow]

What trips? the MCB? Does the tripping device have a 'test' button on it?

 

[Mab40]

Yes the mcb trips,no test button.

 

[mfarrow]

Well if it only trips when the showers actually running then I would suspect the shower is the culprit.

Is there a 30mA RCD protecting the circuit?

 

[Mab40]

no just the mcb it is on an old wylex rewireable fuse CU

 

[mfarrow]

In which case for the sake of about £7 you might as well try replacing the MCB first before calling out an electrician.

Just to be clear - it does only do this when the shower's operating, not at any other time?

 

[Mab40]

yes only when the shower is running but not all the time could go days with out tripping and then trip 2-3 times.

 

[nozspark]

What is the capacity of the Main switch

is it 60A or 100A?

60A main switch wylex boards are not rated for 45A MCBs!

 

[Steve]

60A main switch wylex boards are not rated for 45A MCBs!

I wish I had kept it for evidence (for myself), but I could swear my old 8 way Wylex standard rewireable had a 100A main switch. It also had a 45A MCB fitted with no problems. Wooden back. It only had one block of fuseways.

Though I may be dreaming. And 10mm² cable was a barsteward to get into the terminal holes

Knowing what I know now, and having seen the photos of burned up Wylex standard's I wouldnt fit a big shower on one.

 

[mfarrow]

I wish I had kept it for evidence

and I wish a had a picture of the box in B&Q for a 6-way 60A board in with a 40A MCB exampled on the side. Buy hey, go figure.

 

[nozspark]

Guys....

I was taking about the old Wylex Standard (Domino) boards!!

 

[Mab40]

Main switch is 100A

 

[Steve]

Guys....

I was taking about the old Wylex Standard (Domino) boards!!

So was I . . .

my old 8 way Wylex standard rewireable had a 100A main switch. It also had a 45A MCB fitted with no problems. Wooden back.

 

[mfarrow]

Guys....

I was taking about the old Wylex Standard (Domino) boards!!

Me too!!!