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ExArmy

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when doing an inspection i came accross a radial circuit serving 4 points, the IR between L-N @500V was 0.00 Mohms, on continuity between L-N I got 25 ohms. when I then energised the circuit and clamped the live, no current being drawn. I have yet to take any fronts off as it was just an inspection and i didn't want to start faultfinding, i'm almost certain i got the whole of the circuit and everything was unplugged and they were just plain 2G sockets with no neons, but this one has baffled me. surely if the reading was that low, then there would be about 10A being drawn?
 
Door bell transformer, boiler plugged in, in a cupboard, PIR light, alarm spur, forgotten mobile phone charger plugged in behind bed headboard. These are some I've found recently.

I always do IR at 250v first. L - N value of 0.2 - 0.3 MegOhms usually finds a neon or load plugged in somewhere.
 
Last edited by a moderator:
I would be careful testing between L-N at 500v on an inspection, you may find yourself in trouble if you fry something! I would always test LN-E global at the board and if the result was satisfactory record that for all circuits. If the reading was low then maybe break it down, if you really want to test l-n, soft test at 250v first. I had poor readings about a month ago it was an old mobile charger plugged in, socket hidden the wardrobe.
 
when doing an inspection i came accross a radial circuit serving 4 points, the IR between L-N @500V was 0.00 Mohms, on continuity between L-N I got 25 ohms. when I then energised the circuit and clamped the live, no current being drawn. I have yet to take any fronts off as it was just an inspection and i didn't want to start faultfinding, i'm almost certain i got the whole of the circuit and everything was unplugged and they were just plain 2G sockets with no neons, but this one has baffled me. surely if the reading was that low, then there would be about 10A being drawn?

Are you any further forward with tracing the above?
 
went back today, explained why I was back and said there must be something hidden somewhere that i'm missing as I'm getting a dead short L-N. both of them and me ratched about for 5 minutes before giving up, they were adamant that there was nothing else there. and then just as i got in the van i noticed a light on the outside shed, went back and knocked on the door "theres a light here on your shed, is there power to it?" and the guy replied "yeah thats where the freezer is" !! so then he opens up the shed and theres a double socket of the radial, and a light off the main lighting circuit. so I tested them and they were ok. mystery solved! now i can sleep at night.
 

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