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power up
Has any one ever come a cross this. I went to a customers house that all ready had a two way rcd 63amp 30mil amp board fitted under the stairs on the ground floor with a shower connected on it. I was asked to install a some skt's and lights into the loft. So i ran a 6mm t&e from the ground floor board to a new two way board in the loft. And from the new board ran a small ring main with four skt's on it and a lighting cct with two lihgts on it.when i tested the the new cct's every thing was fine and all reading's satisfactory. But when i done the zs on the ground floor board the reading was fine 0.10 ohms. But when i went to put the earth back into the met there was a small blue spark and when i put a muti meter from the earth cable from the ground floor board to the met there was 110 volt's. I disconnected the l.n.e feeding the loft but had 60 volts on the earth from the shower. So reconnected the loft and disconnected the show and had 65 volt's. I removed the 6mm cable feeding the loft board from the loft board and put it into connector blocks but still had 65 volts even though i have tryed two insulation resistance testers and both read >9.99 across all three core's. So i got one meter of a three core flex wiyh a single skt on one end and with nothing else connected in the board i connected the flex in the board and had 30 volts i then pluged into the single skt a ten meter extension lead and the had 110 volts from the ground floor board earth to the met