There was a RCD with a built-in warning light to say when near the tripping limit, think it was called the X-pole, but google seems to find non-electrical items when I feed that in to the search engine.
Today there is a move from a RCD feeding many MCB's to the use of RCBO's which combines the function of RCD and MCB, if anything it makes fault-finding harder, but does limit what one loses with a trip.
So three tools, the clamp-on
View attachment 401453 shows what is leaking, there is always some leakage, due to using AC, which means some capacitive and inductive linking, but it will only help if it has not tripped, the insulation tester
View attachment 401451 will test when no power, but it uses DC, so it can give false sense of security, and of course the RCD can be faulty so the last one
View attachment 401452 tests the RCD, and shows at what point it trips, your looking at £200 worth of test gear, and also some skill is needed to use it, I have all shown, and I did have the RCBO which covers front kitchen sockets trip, I did the normal unplug all I could, of course it was the last items, which included the dish-washer, I assumed that was the faulty item, so tested it, not fault found, so tested RCBO no fault found, and tested total leakage as you can see just 8 mA, plugged it back in, and it has now been running at least 2 months with no further trips, so even with the equipment and skill, I have no idea why the RCBO tripped.
Hi E,
Interesting, but as I'm not an electrician, and this has only happened once, I'll forget it till next time.
Thanks, C
I have 14 x RCBO's and 2 RCD sockets (latter for UPS supply to freezers) so the trip was inconvenent, but it did not really cause much of a problem. And the previous trip was traced to balcony leaking and a socket had swollen due to arcing inside it, so trip likely stopped a fire, but again with all RCBO protection was easy to turn off that circuit until leak stopped and socket changed. So all in all I like the RCD protection.