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How can I check my garage wiring? Is there something I can use to check that the setup will be able to support a 7kw charger

My setup is a standalone garage (about 4m from the house) with a buried cable all done when the house was built in 1987. I can afford a car but not sure I can afford another group of builders coming in and doing an underground cable to the garage as well.

Thanks
 

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It's almost certain that the cable installed in 1987 was for sockets and lighting for the garage. It's probably 4mm2 ring mains cable. What is it connected to in the garage? Turn off the mains and find a cover to take off and look at the cable. You can always compare it with cable for sale in a DIY or electrical store. You need at least 6mm2 cable for 32A, 7kW.
 

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Hi, remember you can get a grant up to £500 and any electrician can help. You will need a dedicated cable and breaker on your Distribution Board (DB) rated for at least 32Amps(A). Your house probably has a 80A or 100A incoming fuse but I bet you cannot see it because it will be inside a plastic case with a security tag. The charger itself can limit the Amps if necessary but that will lead to longer charging times. Where is your DB reletive to the Charger location and is your meter box on the outside if the house? I am doing a similar install my wife has said she does not want cables on the outside of the house so I am planning an internal route which can be very disruptive.
 

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Forgot to say that the cable size is calculatated determined by so many things so I am not even mentioning it now. Distance, location, fixing +++ and how 'good' the supply is to your house (if you have ever had a test this may be available but Electricity Company will advise) The only thing we do know up to now is operating Amps! (32).
Craig
 

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How can I check my garage wiring? Is there something I can use to check that the setup will be able to support a 7kw charger
I'm afraid it's extremely unlikely it will be able to.

Simplest initial check is what rating is the garage circuit breaker in your consumer unit.
 

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I am doing a similar install my wife has said she does not want cables on the outside of the house so I am planning an internal route which can be very disruptive.
Took the coward's way out myself and waited until the wife was away on a long school trip and then agreed a route on the outside of the house to avoid wrecking the inside. Reckon once we paint over it and remind her we've future-proofed the house she'll come round, I hope!

What you described is exactly what we went though as well. Remember though, if an acceptable route can't be found for a 7kW cable, then a 3kW might be enough (check against your average daily mileage) although I don't know for sure if that could just be run from an existing fuse box in the garage.
 

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Discussion Starter #7
I'm afraid it's extremely unlikely it will be able to.

Simplest initial check is what rating is the garage circuit breaker in your consumer unit.
Thanks and thanks to all the people who've replied.

There isn't actually a connection in the consumer unit. It goes straight from the meter. I'll see if I can get up to the fuse unit in the garage and have a look at the cables.
 

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There isn't actually a connection in the consumer unit. It goes straight from the meter. I'll see if I can get up to the fuse unit in the garage and have a look at the cables.
AIUI meter tails are only allowed to be 2m long. Aside from that, given the size of them it's extremely unlikely anyone would do a 4m underground run like that.
So either there is a fuse or breaker somewhere near the meter or you have a very unusual and probably illegal and/or dangerous installation.
 

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Obviously isolate the supply to the garage before poking about and measuring the cable size.

If you cant find the supply circuit breaker (etc) for this circuit its time to call an electrician.

regards, be safe
 

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Thanks and thanks to all the people who've replied.

There isn't actually a connection in the consumer unit. It goes straight from the meter. I'll see if I can get up to the fuse unit in the garage and have a look at the cables.
As above - safety first. You should be able to get a company to come round to provide a free estimate of the work required to install a unit under the OLEV grant. Get this done and post their recommendations here and the hive mind will interpret them for you.

FWIW I would aim for a 7 kW charge point if you are applying for the grant on the basis that it future proofs you and that it is a lot more expensive to upgrade later.
 

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2nd that from mikegs. But a local electrician will advise you for a very reasonable price seriously. I think you are in a better situation than 99% of readers of this forum. Ref separate supply to garage. A quick check will answer all your questions.
 

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Discussion Starter #12
AIUI meter tails are only allowed to be 2m long. Aside from that, given the size of them it's extremely unlikely anyone would do a 4m underground run like that.
So either there is a fuse or breaker somewhere near the meter or you have a very unusual and probably illegal and/or dangerous installation.
Eek! Hopefully there is some proper stuff in there. Given the state of the house (1980s persimmon or whatever they were called then) build I'd be worried it might be both illegal and dangerous. I will have to get it checked out anyway so maybe this is a blessing in disguise.
 

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No, there will be a circuit breaker for the underground run to the garage. You just need someone who is competent to recognise it, activate it and who knows how to check that the circuit is properly deenergised before poking around. That person almost certainly I not the OP guessing by his questions.

Also, my pennys worth is not to get the charger installation companies involved in the investigation and design side of things. They will make a mess of it, its not within their business models to do a good job.
 

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How can I check my garage wiring? Is there something I can use to check that the setup will be able to support a 7kw charger

My setup is a standalone garage (about 4m from the house) with a buried cable all done when the house was built in 1987. I can afford a car but not sure I can afford another group of builders coming in and doing an underground cable to the garage as well.

Thanks
Can I just check something. Do you need to do this. The etron charger with commando (blue adaptor) can pull 15A and give you a full charge in 20 hours (about 10miles/hour). A 6 hour overnight charge should be good for 60 miles or over 20k per year.
 

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Get a survey done, it will pay in the end.

I had an on site survey done before deciding on going ahead with the charger installation, it would have cost me £60, because the survey found the power supply was good enough I gave the go ahead with the installation.



The survey cost was covered by the installation cost.
 

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Now that sounds like me:)
Fair enough.
Seriously though, this is not like adding an extra light or socket in the house, though even those can be challenging.
This is a substantial addition and upgrade. As said above, get (or pay) someone competent to check the existing system over before getting a charge-point installer involved. Forewarned is forearmed.
 

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Discussion Starter #18
Fair enough.
Seriously though, this is not like adding an extra light or socket in the house, though even those can be challenging.
This is a substantial addition and upgrade. As said above, get (or pay) someone competent to check the existing system over before getting a charge-point installer involved. Forewarned is forearmed.
I just want to be prepared for when we get the car. Having a large double garage wouldn't be much good if we can't charge it in there. Thanks again folks
 

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A car that lives inside the garage! Now there is a novelty. :)
I commend it. We have our EVSE half way down the inside garage wall and can charge the EV (a Zoe) either in the garage, or on the drive with the cable passing out via a cut out in the bottom of the door frame at ground level. It works really well. In the winter the car is at least 5 degrees warmer than if left out on the drive, so we get more range.
 
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