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Discussion Starter · #1 ·
I'm considering running the cable from the garage to my Fuse board and meter myself because the extra on quotes is quite a bit.

Can I double check that 6mm twin and earth is what is needed (17m run from inside garage, under first floor floorboards across width of house and then down under the stairs to where the meter and Fuse board is located) and e.g the Prysmian stuff from B&Q is fine and meets whatever standard required.

Also I saw in another thread a recommendation to run an Ethernet cable. It's this because some charge points need them (I'm looking at Ohme mainly which uses a sim but I think I have quite a bit of spare Ethernet somewhere).

Thanks
 

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Corsa-e 2020
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I’m sure the electricians on here will provide some educated advice. However I suspect that your choice of cable size, routing and length are going to come in for some questioning.

Even without knowing very much about electrics, if you’re going to want to charge at 7.2kW and your supply is above 230v, that cable would need to support 32amp for a sustained period which means you’re going to need a 40amp fuse.
 

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Mitsubishi Outlander PHEV Design 2.4
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You are fitting a complete new circuit from your consumer unit/fuse board, I am not an electrician, you can carryout the work yourself but will have to get the work signed off by a qualified electrician.
 

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Discussion Starter · #4 ·
You are fitting a complete new circuit from your consumer unit/fuse board, I am not an electrician, you can carryout the work yourself but will have to get the work signed off by a qualified electrician.
Ok, understand, my plan was to lay the cable loose but do the effort of lifting the floorboards and putting it through one awkward routing, not connect the ends or anything.

Alternatively I can run a dummy wire which should still help pull the cable through.
 

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Nissan LEAF30
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You will probably be OK with 6mm^2, but really you need to check what voltage is at the start of the run preferably with a significant load on the house (such as the immersion heater and electric oven on if you have them) to know what voltage drop is acceptable. Ask your Sparky what they recommend and what discount they will give you for running the cable.
Don't buy cable from B&Q - it's ridiculously expensive. Your Sparky may provide it for you at wholesale prices.
 

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Discussion Starter · #7 ·
Only advice I'd offer is to get an electrician onside before you do anything rather than trying to find one afterwards. Some are happy enough for the customer to do a load of donkey work so long as they're consulted first.
Yep good advice, will definitely clear it with the installer first. We've agreed the route but his lack of confidence of the final step of the routing is adding to his quote. I think even if I can do the leg work of showing a dummy wire route it will cut the cost. For context my dad was an electrician and I've had my fair share of being the help pulling wires as we've rewired his house a couple of time and changing sockets etc. But I'm not going near a fuse board etc.

You will probably be OK with 6mm^2, but really you need to check what voltage is at the start of the run preferably with a significant load on the house (such as the immersion heater and electric oven on if you have them) to know what voltage drop is acceptable. Ask your Sparky what they recommend and what discount they will give you for running the cable.
Don't buy cable from B&Q - it's ridiculously expensive. Your Sparky may provide it for you at wholesale prices.
At the moment I'm taking to OLEV installer companies who I'm sure are marking up the materials anyway! But thanks for the pointer, will need the drop measured.
 

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Kia eNiro 4+, White
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This is the sort of thing where the cable is expensive, but buy bigger cable as its a one time expense and doesn't cost that much more. If you think you need 6mm, then put in 10mm along with at least one, but preferably multiple Cat5e+ cables. You don't need to terminate the Cat5e's until you need them - but if you are running cable under floors / through walls etc do it right once

I initially put 6mm SWA into my garage (about a 10-15m run as it was more than I could possible use) but recently upgraded to 16mm as the 6mm wasn't enough as plans changed and evolved
 

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The cable spec required depends to a certain extent on the upstream protection and the protection offered from say nails or screw penetration. If you ever want the installation signed off, you would be advised to consult a sparky and follow his guidance with a view to getting him to complete the certification Probably best to forget the OLEV grant. Note that running cables under floorboards requires specific clauses in the Wiring Regulations to be followed. You basically have the choice of ensuring that the cable is a minimum distance below the floorboards, or is mechanically protected, or is RCD protected.
 

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The cable spec required depends to a certain extent on the upstream protection and the protection offered from say nails or screw penetration. If you ever want the installation signed off, you would be advised to consult a sparky and follow his guidance with a view to getting him to complete the certification Probably best to forget the OLEV grant. Note that running cables under floorboards requires specific clauses in the Wiring Regulations to be followed. You basically have the choice of ensuring that the cable is a minimum distance below the floorboards, or is mechanically protected, or is RCD protected.
And some building regs to follow if drilling joists too (I know these are often ignored).

it’s also often a bit of a shock how hard despooling and threading SWA is without a helper.....
 

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When I had my charging point installed, the electrician said it was fortunate the (unused) armoured cable I already had running into the garage was 10mm as if it had been 6mm, I'd have to pay for a new cable. No idea if that was legally correct or not under the regs.
 

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ID3 1st & e-Golf
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I ran the cables for my charge points. I asked for quotes on that basis as it was a long run and I wanted the cables as hidden as possible.
Once I'd chosen the installer they were happy to tell me which cable I needed, it saved them the hard work or running cables through my loft.
I bought the cable online, there are plenty of wholesalers selling online.
 
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