RCD consumer unit

[Will4928]

Since my old fuse box was replaced by a RCD new consumer unit about 2 months ago there have been  two RCD trips which were immediately reset. I have been told by an electrician that in order to reduce the likelihood of future false trips I need to unplug all appliances after use.

Could you enlighten me on the reasons for this. Many thanks

 

[Andy™]

there should be no need to unplug anything. if its tripping then there is a fault and its doing its job. it could be something on the fixed wiring or an appliance, in which case unplugging it will stop it tripping, however the appliance should then be repaired / replaced.
 

 

[Doc Hudson]

Since my old fuse box was replaced by a RCD new consumer unit about 2 months ago there have been  two RCD trips which were immediately reset. I have been told by an electrician that in order to reduce the likelihood of future false trips I need to unplug all appliances after use.

Could you enlighten me on the reasons for this. Many thanks

The reason for this is incompetent advice in my opinion. Electrically intact appliances and wiring will not trip an RCD during normal use or if left connected while not in use. If something is tripping then, there is a fault somewhere on your installation that the RCD is detecting and thus removing the power to prevent the risk of electric shock. The thing you need to do is identify the faulty appliance or wiring and get is repaired or replaced. This may be more difficult to do if you have a badly designed fuse box where one RCD is connected to several circuits. (There is a wiring regulation that requires fuse box configurations to be designed to minimise inconvenience in the event of a single fault, i.e. not relying on a single RCD for large parts of the installation). If your installation was correctly tested and certified when the fuse box was replaced, (2 months ago), then all of the fixed wiring should have been tested and documented on the multi-page electrical certificate you received once the work was complete. So that would narrow the problem down to appliances / accessories connected. But if you don't have the full installation test certificate, it is possible that the wiring has not been fully tested, so it could also be faulty cable somewhere? But unplugging items is a completely unnecessary exercise, for correctly wired and electrically intact installations. You may have a badly designed installation with too many circuits with natural leakage approaching 30ma all connected back to the one RCD?

Doc H.

 

[Murdoch]

I'm wondering if your recollection of the advice maybe incorrect... or incomplete.

In cases of "random" RCD trips, its often a good idea to unplug unnecessary items to help eliminate them from the "cause". 

Chief suspects are normally items with heating elements in them ........ such as kettles, irons, toasters, washing machines, microwaves, tumble dryers, immersions, cookers etc .. fridges and freezers can also cause trips due to the compressors in them

I normally suggest to clients that they keep a  record of what was being used when the trip occurs ............. to help narrow down the issue.

As for any testing ........... I would suggest getting the RCD's re-tested and compare the readings with those on the certificate you were given, plus ramp testing them to see when they trip. A test using an earth leakage clamp meter may also make sense too.

Hope this helps

 

[kerching]

Quote......This may be more difficult to do if you have a badly designed fuse box where one RCD is connected to several circuits. (There is a wiring regulation that requires fuse box configurations to be designed to minimise inconvenience in the event of a single fault, i.e. not relying on a single RCD for large parts of the installation).....unquote

my point exactly!   1 RCBO per circuit, you know it makes sense 

 

[Will4928]

Thank you for all your replies. I forgot to mention that there was a  double faulty socket  ( after the two trips) where a plug could only 90% engage into either socket. The double socket has since replaced  so it is possible this may have contributed to the problem. This was done last week. I have to now wait and see....