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Discuss Help !!! Main switch tripping in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

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Hi Everyone,

Sorry if I am being stupid with this ( its late and i'm very tired)

Still learning and have had a call from a customer that their main switch (not mcbs) keeps tripping everytime they plug in a hoover, heavy duty drill, microwave, kettle into the socket circuit (all the house sockets are on the same ring circuit - 32a type b 2.5mm cable). The socket circuit works with all other items plugged in ( tv, fridge etc)

It also trips when they turn on the shower which is on its own circuit (45a type b) 10mm cable.

I am presuming this is an overload problem?? without seeing it yet thats all the info i have.

Can anyone help me with this? Has anyone come across this before? Could it be something else?

I hope you can help


The Innkeeper
Staff member
I would say that the main switch that they are reffering to is an RCD protecting multiple circuits. If so then i could be a number of things. The RCD would need to be tested first off to make sure it is working correctly.


Thank you, if the RCD is working correctly what would you then suggest?


Scouser and Proud of It
Respected Member
a thorough test for leakage either on appliances or on the circuits. always difficult when you have an RCD/main switch for the whole installation. process of elimination . could be a combination of leakages taking the RCD above it's tripping threshold.


Electrician's Arms
My money is on the fact its a RCD and there's a N-E fault!
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