thoughts please

[wiganspark]

i went to look at a new development yesterday that was in the middle of second fix stage,bit of a strange set up and wanted your thoughts and what regs have been contravened

external meter cupboard
3core 16mm swa terminated into plastic switched fuse then ran to consumer unit inside
terminated directly into plastic CU
inside core used as the main earth terminated into earth bar in the consumer unit
16mm earth taken from earth bar which then Is terminated onto the swa armouring by a bonding clamp to provide an earth.

just seems like an absolute mess and a long winded exercise rather than just using a metal clad switch fuse

 

[NDG Elecs]

How is the armour terminated at the switch fuse end? A proper gland should be installed on one end as far as I am aware, a 951 clamp is not sufficient. The use of plastic instead of metal is not an issue, it would be more solid and a better job in a metal clad board, but as long as the s/fuse and CU casings are not all twisted it is not breaking any regs.

Others on here will be able to give a more definitive answer as some of the above may not be entirely correct...I consider myself still learning..

 

[wiganspark]

it is terminated with a BW gland, if using a metal switch fuse the earth could have been provided there

 

[davesparks]

How is the armour terminated at the switch fuse end? A proper gland should be installed on one end as far as I am aware, a 951 clamp is not sufficient. The use of plastic instead of metal is not an issue, it would be more solid and a better job in a metal clad board, but as long as the s/fuse and CU casings are not all twisted it is not breaking any regs.

Others on here will be able to give a more definitive answer as some of the above may not be entirely correct...I consider myself still learning..

There should be an SWA gland at both ends.

In the op's situation it would have been easy enough to fit the banjo supplied with the gland at the time of installation.

 

[NDG Elecs]

There should be an SWA gland at both ends.

In the op's situation it would have been easy enough to fit the banjo supplied with the gland at the time of installation.

Yep, it would have been easy as you say.

I thought it was the case of the armour having to be properly terminated and earthed at one end as a minimum. Not ideal I know, nor good workmanship, for the sake of 15 minutes extra work....

 

[wiganspark]

There should be an SWA gland at both ends.

In the op's situation it would have been easy enough to fit the banjo supplied with the gland at the time of installation.

thanks for that but what is your thoughts on a bs 951 clamp being used on the swa

 

[BreakingBad]

is the bonding clamp for a supplementary bond only ? and not being used as a functional earth

 

[Sintra]

thanks for that but what is your thoughts on a bs 951 clamp being used on the swa

A BS951 clamp should not be on the SWA no ifs or buts.

 

[Leesparkykent]

134.1.1 "good workmanship by skilled or instructed persons and proper materials shall be used in the erection of the electrical installation. The installation of electrical equipment shall take account of manufacturers' instructions".

BS951 bonding clamps are designed for clamping on to solid pipes. The force required to make a reliable tight joint on to a SWA cable would effectively deform the cable and may loosen over time due the continued deformation of the cable.

 

[PEG]

134.1.1 "good workmanship by skilled or instructed persons and proper materials shall be used in the erection of the electrical installation. The installation of electrical equipment shall take account of manufacturers' instructions".

BS951 bonding clamps are designed for clamping on to solid pipes. The force required to make a reliable tight joint on to a SWA cable would effectively deform the cable and may loosen over time due the continued deformation of the cable.

Precisely...but sadly,there are so many people flouting this specific point,others view the plentiful examples,and accept it as conforming.

Inspected one this week,where installation was similar to the OPs',and the clamp had been fitted 150mm from the end,with SWA sheath removed just enough to allow clamp band...very neat and tidy...very wrong :blush5:

 

[Plonker 3]

Who needs a BS951 clamp!

 

[7029 dave]

Who needs a BS951 clamp!View attachment 30441

See this too many times, that's the trouble with self connect provision.

 

[Flanders]

Who has self connected That ? A plumber !!! If you terminate a cable like that you are defiantly not an electricuian

 

[rustynails]

That's an interesting picture, 100A main switch owned by electricity supplier not to be touched by average spark, a struggle to fit a switch fuse in which should be metal and they are bigger... and not to mention shoddy termination on the swa...

 

[amlu]

looks like a temp supply to a site wired by builder monkeys.
that isolator switch is to be touched by average spark to save them pulling the fuse.
terminate that swa into a small metal box alongside meter cabinet, bit of a squeeze but a switch fuse can go in there too.