08-08-2017, 09:32 PM
More than likely a bit of water in the outdoor cable or a joint in it. You really need a megger to check the insulation, a low voltage test may well not find any problem.
Since it's intermittent it could be a marginal insulation fault or possibly something that gets wetter and dryer from time to time.
An isolating transformer feeding the relevant circuit is a sort of fix but not really recommended as it leaves a dubious and leaky circuit outdoors just waiting to give somebody a nasty shock.
Having a single RCD protecting the whole isntallation is a nuisance. The most recent (17th ed) wiring regs require that the load be split between at least 2 RCDs. Even better is to an RCBO (combined MCB and RCD) for each circuit. Though that's an expensive method.
Since it's intermittent it could be a marginal insulation fault or possibly something that gets wetter and dryer from time to time.
An isolating transformer feeding the relevant circuit is a sort of fix but not really recommended as it leaves a dubious and leaky circuit outdoors just waiting to give somebody a nasty shock.
Having a single RCD protecting the whole isntallation is a nuisance. The most recent (17th ed) wiring regs require that the load be split between at least 2 RCDs. Even better is to an RCBO (combined MCB and RCD) for each circuit. Though that's an expensive method.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
