Hi all.
First post so be gentle.
I live in an old farmhouse with pretty ancient wiring. Split consumer unit with rcd on ring main side, and a separate rcd protecting that consumer unit and supply to outbuildings (via a second consumer unit in the outbuildings).
Last Friday started getting the rcd, either the one on the consumer unit, or both, tripping out, sometimes accompanied by the 'living room/kitchen sockets' mcb going too.
Did the usual, unplugged everything in the house (except the fridge, which has it's own mcb, and the cooker, likewise). slowly started adding stuff but didn't find anything that caused a trip. Tried measuring resistance live & neutral to earth on all appliances, found a pump in the fish tank that was 3 Mohm and the TV runs at 8 Mohm, but I figure it has to be 8k or less to get 30mA? Disconnected them anyway. Still tripping out. Bloody annoying weekend.
So, my question to the panel is: In order to determine where the fault is, should I hire a Megger and test all appliances? Why is it so intermittent? Also, things like the fish tank need to be on all the time, if I temporarily remove the earth from the extension lead running that and protect it instead with a plug-in RCD will that 1) be moderately safe and 2) prevent the main RCD going if there is an issue with the tank?
Also, last night I had eveything turned on except the mcb for the suspect circuit, and the consumer unit rcd tripped - does that rule out the suspect circuit? Or could it still be a neutral/earth issue?
Or should I just call a sparky? Ta in advance.
First post so be gentle.
I live in an old farmhouse with pretty ancient wiring. Split consumer unit with rcd on ring main side, and a separate rcd protecting that consumer unit and supply to outbuildings (via a second consumer unit in the outbuildings).
Last Friday started getting the rcd, either the one on the consumer unit, or both, tripping out, sometimes accompanied by the 'living room/kitchen sockets' mcb going too.
Did the usual, unplugged everything in the house (except the fridge, which has it's own mcb, and the cooker, likewise). slowly started adding stuff but didn't find anything that caused a trip. Tried measuring resistance live & neutral to earth on all appliances, found a pump in the fish tank that was 3 Mohm and the TV runs at 8 Mohm, but I figure it has to be 8k or less to get 30mA? Disconnected them anyway. Still tripping out. Bloody annoying weekend.
So, my question to the panel is: In order to determine where the fault is, should I hire a Megger and test all appliances? Why is it so intermittent? Also, things like the fish tank need to be on all the time, if I temporarily remove the earth from the extension lead running that and protect it instead with a plug-in RCD will that 1) be moderately safe and 2) prevent the main RCD going if there is an issue with the tank?
Also, last night I had eveything turned on except the mcb for the suspect circuit, and the consumer unit rcd tripped - does that rule out the suspect circuit? Or could it still be a neutral/earth issue?
Or should I just call a sparky? Ta in advance.
