I think it's another of these anomalies that crop up from time to time. It is best working practice to install unbroken conductors, but not actually a requirement of BS7671.
Cross Bonding of main bonding gas and water on PIR
- Thread starter danrich123
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This is not a recognised fault on one of the inspection boards and if a candidate insisted that was a fault and refused to seek further into that area of that board he would be failed for not identifying one of the twelve specified by C&G as pass criteria.
The recommendation comes from the NICEIC snags book on earthing. It is not a statutory or non-statutory requirement to do it.
Imagine for a moment a 70mm² line conductor and the minimum requirement for a TNC-S of a 25mm² for the main protective bonding. Would you try to loop it around the connection? Strip the insulation and twist it open and connect through it? Probably not. Using compression lugs with a suitable hole would be the favoured choice and to do it the conductor has to be broken.
I tell my candidates that if it is broken and not using lugs this is not best practice for the reasons stated in the NICEIC snags book.
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It's also in Fig 4a, 4b and 4c of the 16th Edition On-site Guide, but removed in the 17th. As you will recall, much the contents of the OSG were once part of the regulations, but were removed as being the 'good practice' parts, and not real regulations.
Yep, it does appear in section 21.4.
If you want access to BS online you can apply to a library and they will give you a code to view them (except BS7671)
seeing as it is allowed to use struuctoral metalwork as a bonding conductor it must be broken somewhere to connect to the MET and earthclamp if used.
I suggest it is just best practice in order to make it as secure as reasonably possible in all forseeable circumstances and yes I would use seperate conductors or one unbroken one to bond
I suggest it is just best practice in order to make it as secure as reasonably possible in all forseeable circumstances and yes I would use seperate conductors or one unbroken one to bond
I would think that by continuous it would mean that you cannot, for instance, take a 10mm cable to the water pipe and clamp it and then install a secondary clamp on the pipe and take a 10mm cable from there to the gas. Two lugged cables or infact two cables either side of the screw on the clamp are not an issue imo although when installing myself, and using this method I personally like to remove an inch of insulation and bend the exposed cable around the screw.
It's not supposed to be. Your test centre isn't reading the course handbook... nothing unusual there, then.
The Snags and Solutions book (Apr 2005) makes reference to 528-02-04 which is now given under 528.3.3 and states
"Where an electrical service is to be installed in proximity to one or more non-electrical services it shall be so arranged that any foreseeable operation carried out on other services will not cause damage to the electrical service or the converse"
but it says under the Snag 43 title that
"main.....bonding conductors should, ideally, not be looped from service to service"
"Where an electrical service is to be installed in proximity to one or more non-electrical services it shall be so arranged that any foreseeable operation carried out on other services will not cause damage to the electrical service or the converse"
but it says under the Snag 43 title that
"main.....bonding conductors should, ideally, not be looped from service to service"
You should have gone to an award-winning centre!Half to be expected, they managed to run the whole course without reference to GN3
You should have gone to an award-winning centre!Half to be expected, they managed to run the whole course without reference to GN3
I did
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