Mix of 16mm and 25mm Meter Tails

[7029 dave]

Yes that cutout will only except safely 16mm tails, 25mm is too big and the risk of exposed copper showing,80A is fine with 16mm tails, see loads of this type of cutout with 60A service fuse.

 

[Andief]

New on here so be gentle. The cut outs that will only allow 16mm can be used with 25mm. its a case of stepping the insulation and the inner protection then fits through the opening and the outer protection sits flush or just inside the opening on the cut out. Thats assuming its a 100 amp fuse in the cut out. Our COP states that we can use 16mm for 60 -80 amp fuses but must be 25mm if its 100.

 

[kevkdg]

New on here so be gentle. The cut outs that will only allow 16mm can be used with 25mm. its a case of stepping the insulation and the inner protection then fits through the opening and the outer protection sits flush or just inside the opening on the cut out. Thats assuming its a 100 amp fuse in the cut out. Our COP states that we can use 16mm for 60 -80 amp fuses but must be 25mm if its 100.

Hi, in this instance my fuse is fitted is 80 amp and I think the Henley Series 3 Cut Out is only rated to a max of 80 amps too.

I guess the meter fitter was happy to leave the 16mm tails in place. It was just interesting why he went with 25mm from the meter to the isolator. I guess it is future proofed to a point that way!

 

[Andief]

Hi, in this instance my fuse is fitted is 80 amp and I think the Henley Series 3 Cut Out is only rated to a max of 80 amps too.

I guess the meter fitter was happy to leave the 16mm tails in place. It was just interesting why he went with 25mm from the meter to the isolator. I guess it is future proofed to a point that way!

Your guess is a good as mine as to the 25mm cable between the meter and isolator considering the tails to the CU look like 16mm. The future proofing would be pointless in my opinion as if you went up to 25mm on the CU tails i would think you would be upgrading to a 100 amp in the cut out and the 16mm would require an upgrade as well. Ill pose the question to some of my team and see what they say but its beyond me to be honest. 25mm is fail safe to a point bearing in mind that the main incommer is generally 16mm in most installs I deal with. re another comment about identification I wish i had shares in cable ties as we have to put them on every cable x1 on the supply x2 on every load and x3 if its off peak. I recon each install = 2 rain forest trees and a monkey !!!!

 

[SHFW74]

Your guess is a good as mine as to the 25mm cable between the meter and isolator considering the tails to the CU look like 16mm. The future proofing would be pointless in my opinion as if you went up to 25mm on the CU tails i would think you would be upgrading to a 100 amp in the cut out and the 16mm would require an upgrade as well. Ill pose the question to some of my team and see what they say but its beyond me to be honest. 25mm is fail safe to a point bearing in mind that the main incommer is generally 16mm in most installs I deal with. re another comment about identification I wish i had shares in cable ties as we have to put them on every cable x1 on the supply x2 on every load and x3 if its off peak. I recon each install = 2 rain forest trees and a monkey !!!!

I am having UKPN move fuse and meter to outside wall but been told that as the Distribution Board is still in the under stair cupboard in the middle of the house, I would need to run an armoured cable from the isolator in the meter box to the distribution Board. The fuse is going to be upgraded from 80A to 100A and the armoured cable will need to be about 15m point to point. Will 25mm 3 core SWA be adequate for the the cable or should we be looking at fitting 35mm 3 core SWA over that distance?

 

[R-fur]

I am having UKPN move fuse and meter to outside wall but been told that as the Distribution Board is still in the under stair cupboard in the middle of the house, I would need to run an armoured cable from the isolator in the meter box to the distribution Board. The fuse is going to be upgraded from 80A to 100A and the armoured cable will need to be about 15m point to point. Will 25mm 3 core SWA be adequate for the the cable or should we be looking at fitting 35mm 3 core SWA over that distance?

25mm will be fine but you will also need a switch fuse within three meters of the Meter.

 

[SHFW74]

25mm will be fine but you will also need a switch fuse within three meters of the Meter.

Thanks. UKPN are fitting new fuse in meter cupboard with meter. The isolator switchbwill be fitted in meter cupboard between the meter and SWA cable. Are you saying I also need an additional switched fuse between the meter and the isolator as UKPN didn’t mention this