Question About Safety And Main Isolation Switch

[Murdoch]

I think that they will ONLY connect the earth once all the buildign work is complete!

 

[NewHomeowner]

Great.  Thanks again, Murdoch.

 

[ProDave]

...'.  I can open up the 'rose' in the front of the fuse, and loosen the four screws which I guess hold the earth plate securely in place, but there is no obvious 'knockout' or similar for me to route the earth cable through on the right hand side - there's little space, so I can't easily see, but to me it seems there is just the solid plastic casing.  As this is the main fuse, I certainly don't want to attempt to drill a hole in it and shatter it.

So my question is this - should I call the Electricy Supply Company and ask them to call out?  Or does anyone think I can safely attempt to create an access in the right hand side of the casing?

There is indeed a knock out

There are 4 screws under that plastic cover. There are two holes horizontally in the brass block. So you can fit two earth wires one lining up with the top pair of screws and one lining up with the bottom pair.

And there are 2 knock outs one for each earth wire entry. They can by quite tough to knock out.

 

[apprentice87]

I think you need to get a proper electrician...... What makes you think that you, have to / want to / need / should. stick the earthing conductor in here??? Do you know what earthing system they are providing you with??

Do NOT do what you are proposing under ANY circumstances......

What you need to do it this, They have provided an isolator for you, yes?? You have provided a CU yes? You should ALSO have provided a MET. They would then have connected the live terminals up to the supply side of the isolator, and they would have connected an earthing conductor [iF they were providing an earth] to your MET.

You would then have run your tails from your CU to the load side of the isolator, and earth from the MET to the CU earth bar.

john...

 

[Murdoch]

I think you need to get a proper electrician...... What makes you think that you, have to / want to / need / should. stick the earthing conductor in here??? Do you know what earthing system they are providing you with??

Do NOT do what you are proposing under ANY circumstances......

What you need to do it this, They have provided an isolator for you, yes?? You have provided a CU yes? You should ALSO have provided a MET. They would then have connected the live terminals up to the supply side of the isolator, and they would have connected an earthing conductor [iF they were providing an earth] to your MET.

You would then have run your tails from your CU to the load side of the isolator, and earth from the MET to the CU earth bar.

john...

If its a building site the supplier may insist on a TT'ed system!

I had exactly this situation a few weeks back. Nice new suppliers cut off "sealed" and the TT rod a few metre away. Courtesy of EDF/UK PN

 

[binky]

I had to move the CU!

The EDF man said they do not allow switched fuses, they do not allow isolators, or anything else in their meter cupboard!

 oh that's right, the meter cupboard that belongs to the customers if it needs repairing. WPD fit cupboard with back board marked into sections - theirs and ours, get  abit funny if you run an SWA through their side to get a suitable bend though

 

[apprentice87]

Hi Murdoch, yes, so far as i know TNCS is banned on sites, so yes, TT it may very well be!!

john..

 

[kme]

DNO`s make you laugh.

I`ve had two supplies installed to a HED, with nothing else on site.

Metering company were a bit iffy - I chucked a rotary iso on the wall, and the guy terminated into there. He also decided he "had to" seal the HED, which WPD had left loose, for me to remove the fuses on upcoming works ( THEY didn`t want a 1.00 am callout to pull fuses.) . They even left me a pair of size 10 KV gloves - cos mine had failed an inflate test earlier..........