upgrade meter tails, or downgrade main incoming fuse??

[GLENNSPARK]

Planet Spongle I think.

What groth of the electrical system, it's a house for gods sake!

i think he might mean growers tony.....

 

[Engineer54]

Regulations, guidance notes, DNO requirements, actual demand figures, and fuse sizes. To be honest the main reason I upgrade to 25mm tails is for an easy/quiet life.

I could demonstrate by readings and/or calculations that 16mm would be more than adequate. The thing is though, it's easier, cheaper, and quicker just to swap the tails out, so I do. The same goes for 10mm to 16mm main earth and 6mm to 10mm bonding in a lot of cases too.

What's easy about dressing and connecting 25mm tails into tight CU enclosures, when in most circumstances isn't actually required anyway?? I maybe missing something here, but how is it ''easier, quicker and cheaper'' to swap out, the existing correctly sized tails for unnecessary 25mm tails??

 

[SLSpark]

What's easy about dressing and connecting 25mm tails into tight CU enclosures, when in most circumstances isn't actually required anyway?? I maybe missing something here, but how is it ''easier, quicker and cheaper'' to swap out, the existing correctly sized tails for unnecessary 25mm tails??

I personally don't find it a challenge to connect 25mm tails into any db I have fitted terminals are more than adequately sized and easy enough to "dress" the 3 meters max of cable

 

[imago]

What's easy about dressing and connecting 25mm tails into tight CU enclosures, when in most circumstances isn't actually required anyway?? I maybe missing something here, but how is it ''easier, quicker and cheaper'' to swap out, the existing correctly sized tails for unnecessary 25mm tails??

They're not too bad to do into a Hager board which is what I use 99% of the time, but I take your point. A 'typical' CU change for me will be on a three bed house built from the '30s to the '70s. A lot of them will have vastly increased loads from the original or even the rewired in the '70s or '80s installation. You are quite right that they're still nowhere near the 100 or even 80 amp draw though. I find customers fall into two categories mostly: 1) Don't care what you need to do, just get on with it. and 2) Read up a bit, or had another 'electrician' in to quote. The larger group is 2). So for me to take time explaining why the 'advice' they've found on the internet, or the "You've got to upgrade the tails." statement by previous sparks isn't necessarily the case takes too long for the additional few quid difference in replacing the tails. If you vary too far from the majority 'opinion' in a lot of cases it can give the impression you're cutting corners.

 

[Engineer54]

I personally don't find it a challenge to connect 25mm tails into any db I have fitted terminals are more than adequately sized and easy enough to "dress" the 3 meters max of cable

Just not necessary in the majority of cases!!

I was talking about within the CU, not outside of it. Wasn't saying that terminals weren't adequately sized either. But your not telling me that 25mm tails in a CU, aren't more of a challenge to dress than 16mm. Most UK CU's, don't give you much room for any wiring, some are a real challenge space wise, to fit RCBOS . ..lol!!!

 

[Knobhead]

i think he might mean growers tony.....


View attachment 15772

Special regulations apply there Glenn, you need the 17[SUP]th[/SUP] edition of the Hydroponics Wiring Regulations.

 

[danf1966]

OSG .....2.2.3 minimum tail csa should be 25mm

 

[imago]

OSG .....2.2.3 minimum tail csa should be 25mm

OSG On Site Guide

 

[GLENNSPARK]

OSG .....2.2.3 minimum tail csa should be 25mm

aye and it also shows a nice diagram of a TT system with 16mm CSA main earthing....lol....

 

[GLENNSPARK]

Special regulations apply there Glenn, you need the 17[SUP]th[/SUP] edition of the Hydroponics Wiring Regulations.

the `happy funny farm` eh...lol...:rolleyes4:

 

[danf1966]

where is pic of TT with 16mm main earthing must be something wrong with my eyes.

 

[GLENNSPARK]

its the diagrams of earthing arrangements danf.....

 

[danf1966]

Have a proper look glenn..........i dont see it

 

[Engineer54]

aye and it also shows a nice diagram of a TT system with 16mm CSA main earthing....lol....

That's for those rare occassions where someone has actually provided a real TT system, with a sub 1 ohm Ra, which is by the way obtainable in many areas of the UK...

The trouble being the BGB going and spoiling everything by giving a max of 200 ohms!! Which a 2.5mm wouldn't have any problem with!! lol!!