Home EV charging - circuit breaker rating
Discussion
You need a 4mm cable minimum depending on how far away your garage is from you board - most will fit a 6mm and this will give you a 7.5kw charger which it what I have. Charges our Zoe in around 3.5 hours. This is a not a "fast charger".
A standard 13amp socket will be wired in 2.5mm cable and if often reffered to as a "granny cable" and will take around 12 hours to charge.. not really suitable for everyday use.
A "Fast charger" is typically 22kw but you will need 3-phase power and most houses don't have it. Will charge the car in around 1 hour 15 minutes,
A "Rapid charger" is 43kw, 3-phase and will charge your car to 80% in around 30 minutes.
Most chargers come FOC when you buy a new EV. I now have two from two different deals as the last one came with the car and first one was a government initiative. Which ever you get, it is not a DIY install from a 13a socket in your garage and will require a professional installation.
A standard 13amp socket will be wired in 2.5mm cable and if often reffered to as a "granny cable" and will take around 12 hours to charge.. not really suitable for everyday use.
A "Fast charger" is typically 22kw but you will need 3-phase power and most houses don't have it. Will charge the car in around 1 hour 15 minutes,
A "Rapid charger" is 43kw, 3-phase and will charge your car to 80% in around 30 minutes.
Most chargers come FOC when you buy a new EV. I now have two from two different deals as the last one came with the car and first one was a government initiative. Which ever you get, it is not a DIY install from a 13a socket in your garage and will require a professional installation.
LordFlathead said:
Which ever you get, it is not a DIY install from a 13a socket in your garage and will require a professional installation.
...and a certificate. Its not worth dicking around with (especially when there are grants to cover much of the cost) because when you burn your house down through a bit of dodgy DIY you will have an interesting conversation explaining what accidental damage cover is. This is not wiring a mains plug.The OLEV grants for chargers have dropped a bit - good news its a fairly flat rate £195 for a 16A charger. I paid the extra 90 for a 32A powerpoint to go with uprated charger on our Leaf.
In terms of wiring it was a fresh ( and beefy ) cable from the Consumer unit.
I didn't have space for another breaker either but the sparky combined a couple of low power circuits I had for lights to create a "space"
In terms of wiring it was a fresh ( and beefy ) cable from the Consumer unit.
I didn't have space for another breaker either but the sparky combined a couple of low power circuits I had for lights to create a "space"
My home one was run direct from the electricity supply outside the house in the wall mounted meter box. Electrician connected a separate circuit breaker from the house feed side of the smart meter. So, nothing needed adding to the consumer unit in the house (which is just as well as it hasn't any spare spaces left). Cable was very, very large - not sure what the breaker rating is but think it's a ridiculous 68Amps!
Doe that make sense to anyone?
Doe that make sense to anyone?
Lgm50 said:
My home one was run direct from the electricity supply outside the house in the wall mounted meter box. Electrician connected a separate circuit breaker from the house feed side of the smart meter. So, nothing needed adding to the consumer unit in the house (which is just as well as it hasn't any spare spaces left). Cable was very, very large - not sure what the breaker rating is but think it's a ridiculous 68Amps!
Doe that make sense to anyone?
Cable on mine is 6mm (3x6mm cores) and armoured so it's pretty thick & rating is something like 72A). The breaker is also 68A (IIRC) but importantly had to have a particular surge characteristic to cope with the inrush current on our Renault Zoe. I believe more expensive EVs have some sort of 'soft start' to limit this inrush.Doe that make sense to anyone?
essayer said:
LordFlathead, did you get the charger installed when you bought the Zoe? Did they do a good job running cables back to the fuse board etc or was it surface mount, simple and fast style..?
We have a ring serving our garage but suspect it's only 2.5mm
Charger (the 2nd one) is due to be installed shortly as I'm waiting for a new distribution board to be fitted. The first install was neat with an armoured cable being clipped to the wall low down. We have a ring serving our garage but suspect it's only 2.5mm
Your ring main will not comply with the IEE regs, it needs to be on its own circuit.
Lgm50 said:
My home one was run direct from the electricity supply outside the house in the wall mounted meter box. Electrician connected a separate circuit breaker from the house feed side of the smart meter. So, nothing needed adding to the consumer unit in the house (which is just as well as it hasn't any spare spaces left). Cable was very, very large - not sure what the breaker rating is but think it's a ridiculous 68Amps!
Doe that make sense to anyone?
Renault Zoe has issues with "spikes" so they advise a specific breaker with a higher inrush current. Having said that, the first installation has never tripped my breaker and is a standard Type 2, 32amp, wired in 4mm 2-core. However, the new install even though only 20 metres away will be wired in 6mm 3-core as others have stated.Doe that make sense to anyone?
O/T
A useful tip I have employed to offset EV electricity usage at home was to buy four 105a/h leisure batteries which are connected in a 48v string. Using the economy 7 tariff from BG, I charge these up off peak at 7.2p/kwh along with the car. Then during the early evening, a dedicated ring circuit fed by a pure sine 3kw inverter provides power for my computers, the fridge, lighting etc - everything but the oven, induction hob, washing machine, dryer and room AC's. My electricity bill is now the same as it was before I bought the car! I'm looking at buying more batteries later on. Sorry for the off topic convo, but it's nice to know that you can reduce your electricity bill with a small capitol investment
Quick q - Chargemaster have booked us in tomorrow but also said we need an isolation switch. This will delay delivery of our car etc 
I note that some naughty person has already removed the tag from the fuse and from the meter tails cover, could they potentially wire a second pair of cables into the meter, or split the tails in some way?
I note that some naughty person has already removed the tag from the fuse and from the meter tails cover, could they potentially wire a second pair of cables into the meter, or split the tails in some way?
They would use a Henley block to split to a second CU as you describe.
It's just a junction box with massive terminals, not an expensive item nor arduous for them to fit.
ETA: get them to install isolation switch before the henley block, it's useful to have one for any future electrical works to avoid the need to pull incomer service fuse (the bit with missing tags!)
It's just a junction box with massive terminals, not an expensive item nor arduous for them to fit.
ETA: get them to install isolation switch before the henley block, it's useful to have one for any future electrical works to avoid the need to pull incomer service fuse (the bit with missing tags!)
Edited by donkmeister on Thursday 7th April 17:56
Nathanbarley said:
Main incoming fuse can only be moved by the Supplier or local Network Operator.
What Nathan said.Although as the tags are already missing on your service fuse the spark may be open to the idea of doing it themselves.
Note that pulling a service fuse exposes live parts that are essentially unfused I.e. lethal. Don't be tempted to do it yourself (I can see you won't but you never know who will read in future and think "hmmm, I can do that!")
Gassing Station | EV and Alternative Fuels | Top of Page | What's New | My Stuff