pewter
Conspiracy Theorist™
Earthing can be smaller if not TNCS .... i think
Supplementary Bonding Question
- Thread starter Dairyspark
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Dairyspark
Member
Yeah that's the one I mean pewter 
TNCS is Deffo 10mm bondage incase of broken PEN conductor on the DNO side.
But with TT / TNS as long as it's in good condition and there are no signs of heat damage and readings are of less than <0.05ohms then it doesn't need to be upgraded as far as I know.
But with TT / TNS as long as it's in good condition and there are no signs of heat damage and readings are of less than <0.05ohms then it doesn't need to be upgraded as far as I know.
unless mechanically protected (which it won't be) main earth can be as small as 6mm
:slap
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Dairyspark
Member
Consumer unit was change 10 years ago, sockets were rewired 15 years ago and the lights havnt been touched since he moved in 21 years ago lol
Dairyspark
Member
Any more advice on this please
Rob_the_rich
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why is supplementary bonding in the bathroom relevant to alterations to the ring and lighting circuit in the kitchen/lounge?
The BGB 132.16 says "..the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate."
Looking at ADS (411), supplementary bonding is not mentioned as a requirement of the protective measure, it is an additional protection in a special location, not relevant to the kitchen.
But any extraneous-conductive-parts found on the property would need main equipotential bonding as in 411.3.1.2
The BGB 132.16 says "..the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate."
Looking at ADS (411), supplementary bonding is not mentioned as a requirement of the protective measure, it is an additional protection in a special location, not relevant to the kitchen.
But any extraneous-conductive-parts found on the property would need main equipotential bonding as in 411.3.1.2
pewter
Conspiracy Theorist™
I agree
If altering the kitchen i wouldnt worry about the bathroom. I would advise about the bonding, and that a new consumer unit to RCD everything would make it all a lot safer, and not require the bonding.
If cost is an issue, just protect the circuits you are working on.
If altering the kitchen i wouldnt worry about the bathroom. I would advise about the bonding, and that a new consumer unit to RCD everything would make it all a lot safer, and not require the bonding.
If cost is an issue, just protect the circuits you are working on.
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On TT main earth as small as 2.5mm protected against mechanical damage and sheathed isn't it?
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There is NO SUCH THING as MAIN EARTH in a normal install.
Dairyspark
Member
I'm not worrying about the bathroom, it was to see if the bonding in the kitchen needing replacing, or if the main bonding would be sufficient lol then the only regs I could find were to do with special locations and cost is the main reason I'm only changing the ring circuit to and RCBO
If it is "extraneous" then it needs proper bonding. Supplementary bonding is just that, it is not the same as "proper" bonding.. do the tests Andy told you about to see if they are extraneous first... If they are, then they need proper bonding back to the MET
Test between any simultaneously accessable exposed conductive parts too. There should be very little resistance between them as they should all be earthed by means of the supply CPC. In any case, the resistance between them must be such that the max voltage that could appear between then is 50V, This means, that in the case of circuits protected by a 30mA rcd, the resistance between them must be LESS than 1666 ohms.
Check between exposed bits or extraneous bits and anything else conductive, if the result is more than about 22 - 25 Kohms forget about them, if less, but NOT less than 1666 ohms, supplementary bond them.
john...
Test between any simultaneously accessable exposed conductive parts too. There should be very little resistance between them as they should all be earthed by means of the supply CPC. In any case, the resistance between them must be such that the max voltage that could appear between then is 50V, This means, that in the case of circuits protected by a 30mA rcd, the resistance between them must be LESS than 1666 ohms.
Check between exposed bits or extraneous bits and anything else conductive, if the result is more than about 22 - 25 Kohms forget about them, if less, but NOT less than 1666 ohms, supplementary bond them.
john...
Dairyspark
Member
Great thanks for all the help guys
thanks for all the help guys 
