Earth rods...do i need one?

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ok so thats all a tad clearer, best find a compitant adult to check it out then...many thanks for your time and knowledge..cheers
 
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As a sort of aside though and to temper my obviously 1970's electrical system I trump my own with a friends "hillbilly" electrical system that is currently reducing her house to darkness by eating those low power bulbs, her supply of "proper bulbs" is fast running out!
 
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As a sort of aside though and to temper my obviously 1970's electrical system I trump my own with a friends "hillbilly" electrical system that is currently reducing her house to darkness by eating those low power bulbs, her supply of "proper bulbs" is fast running out!
Interesting. Even a "hillbilly" electrical system didn't really ought to eat low-power bulbs/lamps - sounds like she might need an electricioan as well!

It would be good if you could give us an update after an electrician has looked at your setup and 'deliberated'!

Kind Regards, John
 
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Well currently im on a hunt for an electrician....which round here seems not as easy as one might think. I will keep you informed when i find one. Again thanks for all taking the time to answer my questions cheers..
 
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Well currently im on a hunt for an electrician....
If having no luck you could ask in a letting agency for the name of one of the electricians they use. If that seems odd..... some agencies have a set of tradespeople they use who are reliable and sometimes charge less as the agency feed them work and they don't need to advertise.
 
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If her supply of "low power bulbs" are the non-branded cheap-as-chips variety, this will go a long way to explain it. As will lamps used in oft-used rooms, like lounges, kitchens etc and those with a high frequency of switching.
 
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securespark";p="2900829 said:
If her supply of "low power bulbs" are the non-branded cheap-as-chips variety, this will go a long way to explain it. As will lamps used in oft-used rooms, like lounges, kitchens etc and those with a high frequency of switching.[/quote

Its probably more to do with a set of electrics that seem to out of the arc, the first time i saw the lights dim when the kettle went on i was surprised. But it sort or matches the "farm house" style by farm house i don't mean the sort u get on "escape to the country" more the knackerd landrover, overflowing septic tank and having to bail out the living room if it rains a lot.
 
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oops its taken a while to put finger to keyboard but i did get a electrician to look.....and ... he pointed out the earth rod. I protested that was next doors, he pointed out next doors was along a bit (in my defense, ours is in a different place from all the others in the street. )...the earth wire goes inside the platerboarded porch and out to perfectly good earth rod, that i thought was next doors...i felt an idiot but the guy tested it laughed and said better safe than sorry...again thanks for the info.
 
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So what did he say about the Voltage-operated Earth Leakage Circuit Breaker??

It is no longer deemed safe to have a TT supply (as you have - ie one with an earth rod) without RCD protection.

You need to get RCD protection.

OR a PME conversion done by the DNO.

But if you have PME, you'll need PEB's to gas and water pipes and any other pipework coming in from outside, like LPG or oil.
 
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It is no longer deemed safe to have a TT supply (as you have - ie one with an earth rod) without RCD protection. ... You need to get RCD protection. ... OR a PME conversion done by the DNO. ... But if you have PME, you'll need PEB's to gas and water pipes and any other pipework coming in from outside, like LPG or oil.
Are you suggesting that main bonding is not required in a TT installation?

Kind Regards, John
 
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Er, no. :oops:

Rather, what I meant was that it is crucial in a PME install.
 
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Er, no. :oops: Rather, what I meant was that it is crucial in a PME install.
That's what I rather assumed - but I thought it should be clarified that Main Bonding ('PEB' if you prefer), to incoming service pipes etc., is essential in any electrical installation, regardless of the type of earth.

I agree with you that it is particularly important with PME, but (under some fault conditions) it can also be very important with TT. If, for whatever reason (e.g. no RCD, or faulty RCD) no RCD responds to an L-E fault (and, in general, no OPD will respond to such a fault in a TT installation), then the potential of the installation's MET, CPCs and exposed-conductive parts will rise to not far short of full line voltage. If there were unbonded things (e.g. pipework, aka extraneous-c-ps) within the premises which were close to earth potential, that situation would obviously represent a serious hazard. The saving grace is that there will usually be 'incidental' connections between CPCs and extraneous-conductive-parts, but one obviously should not 'rely' on it.

Kind Regards, John
 
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If, for whatever reason (e.g. no RCD, or faulty RCD) no RCD responds to an L-E fault (and, in general, no OPD will respond to such a fault in a TT installation),
Why's that .. is it because you shouldn't assume that a TT earth will be low enough impedance to trip and over current device?
 
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If, for whatever reason (e.g. no RCD, or faulty RCD) no RCD responds to an L-E fault (and, in general, no OPD will respond to such a fault in a TT installation),
Why's that .. is it because you shouldn't assume that a TT earth will be low enough impedance to trip and over current device?
Exactly. It's not so much a case of 'not assuming' that - but, rather, of assuming that the opposite will virtually always be the case. A standard domestic TT electrode will rarely result in an earth fault loop impedance less than about, say, 40Ω. With that sort of impedance, a negligible impedance L-E fault will only result in a current of 5.75A - not nearly even enough to trip even a B6 MCB on a lighting circuit, let alone higher-rated MCB on other circuits. That's why all circuits in a TT installation must have RCD protection.

Kind Regards, John
 
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