Wylex 80amp Residual Current Circuit Breaker

[gramps]

Greetings to all

Our 1960's semi has a Wyles 80amp Residual Current Circuit Breaker fitted between the mains in and the fuseboard.

In the last 10 days it has taken to randomly tripping, sometimes a couple of times a day (or night) recently not for 6 days - then again today.

There is no pattern to the tripping, it doesn't seem related to times when most power is in use, i.e. teatime with oven going, TV on etc etc and has happened in the dead of night with practically no power in use.

I have used a mini Pat Tester on all appliances and extension leads (1 for computer stuff and another for tumble drier and fridge) and everything tests out as problem free.

I have tested all sockets with a Martindale type socket tester and again all show as problem free.

We did have some redundant external wiring for floodlights but I have completely disconnected that wiring from the circuit so there is no longer any connection to that external wiring.

I realise it is probably going to come down to calling in a local electrician but would welcome any other suggestions of simple checks that I could make before taking that course.

Thanks in advance of any help offered.

 

[Evans Electric]

You made a good start anyway .     The socket tester will probably not help to be honest .      

Disconnecting outside wiring was a good move .  

Another reason can be damp , say inside  a socket  . 

Another can be an old  immersion heater  .  

The fact that the Wylex RCD is there points  to  an earthing problem  ,  presumably highlighted in the 1960s   .       

Have you recently  purchased  a new device ?  

I'd say the next step is to test the RCD  ...even modern ones go wonky for no reason ...   you need a special tester for that .      Also need  an insulation tester .    Maybe  time to get a sparky in . 

Edit :     Get him to test the incoming earth  , it may have been upgraded by now ,  which means you could ditch the RCD .    

               A new consumer would be worthwhile  ,  with  individual  RCBOs   on each circuit  is worth considering . 

 

[Phoenix]

Can we have a picture of the fusebox area including the RCD, fuseboard and supply authority fuse.

When you disconnected the outside light wiring, you did disconnect N as well as L?

What test equipment do you have, ideally an insulation tester is required, but the fault may show up on a multimeter (it may not, but theres a reasonable chance it might)

Where in country are you? Might be someone on here nearby

 

[Andy™]

I have used a mini Pat Tester on all appliances and extension leads (1 for computer stuff and another for tumble drier and fridge) and everything tests out as problem free.

I have tested all sockets with a Martindale type socket tester and again all show as problem free.

whilst PAT may show up faulty items, it will not help wit a fault on the fixed wiring. a martindale type socket tester is also going to be no help to finding the problem. youll need proper test equipment and knowledge of how to use it / fault finding if you want to find the problem

 

[Murdoch]

If its tripping when you are out or asleep this points are devices on 24 / 7 or a faulty RCD (you set up is precisely why single upfront RCD's don't comply with the regs).

Unless you are very lucky you aren't likely to find this by hit and miss testing

Have do or anybody else been "fiddling" with any of the installation recently?

It could be caused by the incoming supply

In such cases I always ask customers to keep a record of when it trips 

If I visited your home I'd be equipped with my earth leakage clamp meter!

Sorry if this isn't helpful