R
Ringo
Got some mystery wiring to figure out - here's the problem (bear with me!):
There's a fairly tatty 3-phase board supplying the workshop where I work. Took the cover off (isolated!) to see a bit of a spaghetti situation, but all in all not too bad. Old colours, spiderwebs and the like. What concerned me was the single 1.5 red cable hanging free ready to liven up everyone and everything (so I thought). There were no empty L terminals, only one ring which was complete... but there was a connector block very nearby with the 2 ring CPCs running into 1 terminal and a single CPC run from the same terminal in the block to the earth bar. Meaning the opposite terminal of the block was empty. Not screwed down though!
With me so far? Good.
It crossed my mind that the loose red was for some reason being used (wrongly) as a CPC and had fallen out of the block. So I got the long lead out and started hunting - tracked the other end (?) to a 3-phase isolator for a CEE socket. In this isolator everything seemed to be in order except there was a 4th red cable, meaning 6 cables were running back to the board (3L, 1N, 1CPC + extra red). This extra red was terminated in a connector block, but connected to nothing else from the block. In the next pair of terminals on the connector strip was the CPC coming from the isolator casing, connected back to the board. For some reason. Continuity fine.
However, I then attached the end of the long lead to this rogue red at the block in the isolator, and tested for continuity back at the board. I got a reading at the other loose end, *and* across the E bar *and* the N bar, nothing between any other phase. So somewhere along the way something connects to something else. But what and why? I know this needs more investigation, and I'll be doing just that, but while I wait for the go-ahead to tear part of the ceiling down and rip the cabling out to start again, does anyone have any ideas about what I may be missing? Any experience or technique that I haven't come across yet that may explain it? Nothing else is fed from this breaker (nothing I can see anyway) - it's a dedicated 3-phase breaker for this one socket.
Thanks.
(Edit - it's possible that at the isolator this rogue red was stuffed in with the CPCs at the block, running back to the block in the board with the ring CPCs! But then why the continuity with N?)
Whew!
There's a fairly tatty 3-phase board supplying the workshop where I work. Took the cover off (isolated!) to see a bit of a spaghetti situation, but all in all not too bad. Old colours, spiderwebs and the like. What concerned me was the single 1.5 red cable hanging free ready to liven up everyone and everything (so I thought). There were no empty L terminals, only one ring which was complete... but there was a connector block very nearby with the 2 ring CPCs running into 1 terminal and a single CPC run from the same terminal in the block to the earth bar. Meaning the opposite terminal of the block was empty. Not screwed down though!
With me so far? Good.
It crossed my mind that the loose red was for some reason being used (wrongly) as a CPC and had fallen out of the block. So I got the long lead out and started hunting - tracked the other end (?) to a 3-phase isolator for a CEE socket. In this isolator everything seemed to be in order except there was a 4th red cable, meaning 6 cables were running back to the board (3L, 1N, 1CPC + extra red). This extra red was terminated in a connector block, but connected to nothing else from the block. In the next pair of terminals on the connector strip was the CPC coming from the isolator casing, connected back to the board. For some reason. Continuity fine.
However, I then attached the end of the long lead to this rogue red at the block in the isolator, and tested for continuity back at the board. I got a reading at the other loose end, *and* across the E bar *and* the N bar, nothing between any other phase. So somewhere along the way something connects to something else. But what and why? I know this needs more investigation, and I'll be doing just that, but while I wait for the go-ahead to tear part of the ceiling down and rip the cabling out to start again, does anyone have any ideas about what I may be missing? Any experience or technique that I haven't come across yet that may explain it? Nothing else is fed from this breaker (nothing I can see anyway) - it's a dedicated 3-phase breaker for this one socket.
Thanks.
(Edit - it's possible that at the isolator this rogue red was stuffed in with the CPCs at the block, running back to the block in the board with the ring CPCs! But then why the continuity with N?)
Whew!
