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Thread: Twisting earth wires together

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    Twisting earth wires together

    Many people who use twin + e or surfix etc seem to think it is not important to actually terminate the earth when twisted together, no load, no power , twist is tight enough, what ever the reason. Well they clearly dont understand what actually happens when there is an earth fault and the current which flows in earth conductor during an earth fault, the temperatures etc. They also dont realise that the earth wire is the MOST IMPORTANT PART of an electrical installation, not the red wire or black wire especially when it comes to faults.

    As some qualified electrician who have some idea what they are doing know that there is constantly expansion and contraction as the wire is loaded generating heat, no matter how small. When it comes to earth wires, you will only know how good the termination is when there is a fault. High fault currents create high temperatures, if the termination is not done correctly chances are that the fault will go somewhere else and not down to earth, where is is suppose to.

    I also find it rather disturbing how inspectors who carry out inspection report treat the earthing as if it is not as important as they should, i can see this by the results on the COCs which, most inspectors just write 0,2 ohms or 0,02 ohms which is a clear indication that they didnt carry out thorough earth test. I have watch how some just use a buzzer and if it makes a noise they regard it as earthed. I believe a loop impedance test should be carried out at each and ever socket outlet and at light fitting with exposed metal parts, with the results recorded at each point, just imagine, that R450 coc would suddenly go to R1450 or would it, once you know what reading you should get, it is easy to just fill it in like people do with the earthing and bonding results.

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    Sparks (02-Dec-12)

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    My favourite is when I find a house with no incoming earth with the supply cable, well the earth cable is there but it just isn't doing much. I do a loop test at the mains position, no reading or a very very high reading, usually picked up from the bonding on the water pipes or something or the metal meter box is actually in the ground. i give the customer a report saying they need to get the municipality out to check why there is no incoming earth. Yes, there is an earth wire there but its somehow not connected to properly. They come out, put a volt meter across live and earth, 230V, then leave. Yes, There is 230V but they don't do a loop test. You sit and explain to them the problem and you get blank looks. After about 4 or 5 visits they send a clever guy who understands and then it gets sorted.

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    Wait till till you do a power quality recording and indicate that there are volt drops or events like spikes and stuff. They still havent found a clever enough guy to understand, so they just up the transfomer tappings.

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    You mean they have kleva guys working there, wow I am impressed
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    I had this problem with volts dropping to 130v. The only thing I can think of was that the over head cables was stolen and replaced small segments with aluminum and I am in the last house of that transformer. The way the clever council fixed it was at the pole there are 2 transformer supplys thy switch me from the one to the other

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    Gold Member Sparks's Avatar
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    When I get a bad loop result I just phone the monkeypality myself and the same day they send someone to rectify it. That is one of the advantages of being on a good footing with them. In one suburb I was getting voltages of 168, I promptly called Sias and he sent someone out to connect a logger for 3 days. This was done simultaneously at a few houses in the area. The result was a whole suburb being rewired. Low supply voltage can become more costly to the supplier if everybody claims new appliances.

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