S
shinypen
Hi. I'm newly qualified as a domestic installer so well aware I've got a lot to learn about the real world but...
I looked over a friends consumer unit today. It was recently installed by a NICEIC approved spark. I noticed lots that didn't seem right to me, and I'd appreciate some feedback on which bits are actually bad and which are just "how it really works on site".
1) There's no main bonding in place to either the gas or water. The certificate has all the relevant boxes ticked to say it IS there and complies with regs.
2) The tails haven't been increased to 25mm and they don't all enter through the same knockout.
3)The main earth comes through a large gland leaving plenty of room to poke a finger through.
4) It's been RECORDED on the certificate as a TN-C-S, and does superficially look like one (it's one big cutout). I'm convinced it's a TN-S. It 100 year old house. There's actually a bit of lead sheath visible near where the cable enters the house and there is continuity between this and the MET.
5) "N/A" is recorded in the Ze box. Maybe related to the confusion between TNS and TNC-S?
6) All of the Zs are recorded as 0.35 ohms. This seems conveniently the same as the TN-C-S Ze requirement of 0.35 ohms so I checked it. Got 0.61 upstairs, 0.48 downstairs and a Ze of 0.19 at the board.
7) The main fuse is still 60amp. The max demand on the cert is recorded conveniently as 60amp.
8) Inside the consumer unit, three 2.5mm neutrals have been joined by wago all in to one 2.5mm neutral and extended to reach the terminal bar. This has also happened with a 4mm neutral to a 2.5mm. Surely this has de-rated the cable?
Many thanks for reaching the end of my long post!
I looked over a friends consumer unit today. It was recently installed by a NICEIC approved spark. I noticed lots that didn't seem right to me, and I'd appreciate some feedback on which bits are actually bad and which are just "how it really works on site".
1) There's no main bonding in place to either the gas or water. The certificate has all the relevant boxes ticked to say it IS there and complies with regs.
2) The tails haven't been increased to 25mm and they don't all enter through the same knockout.
3)The main earth comes through a large gland leaving plenty of room to poke a finger through.
4) It's been RECORDED on the certificate as a TN-C-S, and does superficially look like one (it's one big cutout). I'm convinced it's a TN-S. It 100 year old house. There's actually a bit of lead sheath visible near where the cable enters the house and there is continuity between this and the MET.
5) "N/A" is recorded in the Ze box. Maybe related to the confusion between TNS and TNC-S?
6) All of the Zs are recorded as 0.35 ohms. This seems conveniently the same as the TN-C-S Ze requirement of 0.35 ohms so I checked it. Got 0.61 upstairs, 0.48 downstairs and a Ze of 0.19 at the board.
7) The main fuse is still 60amp. The max demand on the cert is recorded conveniently as 60amp.
8) Inside the consumer unit, three 2.5mm neutrals have been joined by wago all in to one 2.5mm neutral and extended to reach the terminal bar. This has also happened with a 4mm neutral to a 2.5mm. Surely this has de-rated the cable?
Many thanks for reaching the end of my long post!
