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Hi,

Sorry if this has been answered already but I'm nearing towards a M3 purchase.

I'm looking at the Standard Plus but for the the time being wish to hold on to my capital so will probably put off installation of a wall charger for now given that a local sparkie has quoted £1,800. This is because it's not a standard set up where I live and there's a lot of travel for the supply to come off beofre it has to be taken over a roof !

So, I've researched this online but haven't been able to clearly seek an answer. The question therefore is if was to charge the SR+ off my home circuit how much range could you put on an hour?

I'm now home working so the SR+ will sit on my drive for most of the week. There are an abundance of 7KW chargers in nearby NCP's plus the Tesla Superchargers are within reach also as I'm circa 20 miles away for one so I think I could get by without any dramas.

If I can charge on the home circuit (standard 13amp plugs / 240v etc.) more often than not the SR+ will be on charge overnight plus most of the day if needed.

Any guidance welcome!

Many thanks.
 

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The granny charger will charge at around 2.3kW per hour. So around 7 to 10 miles per hour depending on condition. Not recommended for long term use though due to the strain it would place on your wiring.
 

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Renault Zoe 50
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You can use the 13 amp socket and UMC to get by, but be careful. It’s unlikely your wiring was installed with the intent of running 10 amps through it for 20 hours. If it’s old it could start a fire.

If you do this for long periods, then turn the amps down in the Tesla to 8 or so. This will reduce any potential overheating and you won’t notice if you’re not doing huge mileages. Also install a smoke alarm at both ends, if you can.

The other cheap option is to get a 16 amp blue commando socket (as per caravan sites) in place of your socket. Then get the electrician to check the consumer unit end and cable, so it conforms to current regs. This might save you some money, as it sounds like it’s a very long cable run to the CU.
 

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I assume cost included grant? It is worth taking advantage of as probably won't be around for ever and grant installed points have to include 3 year warranty. Certainly get another quote and maybe also look if some of basic labour could be be done DIY or a labourer rather than qualified spark.

Bear in mind that apart from any referral miles, Supercharging (or public posts) cost a lot more than home charging on a cheap overnight rate, such as Octopus Go at 5p kWh. Getting a charging point sooner means you get those savings quicker and it can pay quite a bit towards cost of it - although at present most people aren't driving as much.

If you own your home then bear in mind that in a few years people will be looking for a proper charging point (just like fast broadband today) so it will be a good selling feature and maybe even add a smidge to value.

Anyway, the table below from Tesla shows that for Model 3 you will add ~8 miles an hour at 2.3kW which is max on 13A socket. On a proper 7kW home point you will get ~27!

As above, do be careful with the 13A and check plug regularly - I didn't for a couple of months at rental property and it melted on bottom. It could have been a lot worse...

Warming the car up doesn't work well on 10A either...

OUTPUT CHARGE POINTRANGE ADDED PER HOUR* (M/H)
kWModel 3Model SModel X
16.5404843
11403228
7.4272119
3.7141110
2.3876
 

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Have two Evs and get by fine with just a three pin plug. It’s modern wiring and we don’t do much mileage.
 

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Have two Evs and get by fine with just a three pin plug. It’s modern wiring and we don’t do much mileage.
Sure, but make sure you understand the risks. As well as obvious risk of the (poory designed) UK plug overheating (especially as it ages) there is -
  • If plugged into a ring mains, a loose connection (or break) could cause the circuit to overheat if other high current appliances are plugged in. Connections can come loose at any time, but often occur with vibration - such as drilling a wall.
  • Most portable EVSE do not have DC leakage protection so a fault could blind your house RCD. In that state it would not trip on a house socket or appliance, which could result in injury or death.
  • I don't think any portable EVSE protects against a neutral PME supply fault. In that case your house earth and car bodywork will be at a high voltage to true earth. In that state touching the car outside could result in injury or death.
If you want to just use portable EVSE maybe get a dedicated circuit with a separate RCD as that at least protects against all but supply fault.
 

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Just get an electrician to check everything and go for it. All these doom and gloomers don't help at all! ;)
An electrician check can verify a socket is safe, inspect all connections on a ring and is a good idea. However, they can't magic away some of those EVSE safety risks. To eliminate them you need a proper charging point installed to 18th Regs and IET CoP.

This isn't doom and gloom, it is making sure people using 13A EVSE regularly are aware of risks. If they are happy to take them fine, but I hope we don't see another "my house almost burnt" down posts.
 
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As well as obvious risk of the (poory designed) UK plug overheating (especially as it ages) there is
I managed to melt a shuko socket with one. So not just the design, but more the age and quality of any connections.
 

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Of course you should get an electrician to inspect it and tell him what you intend to use if for.

It’s very likely that he may say the wiring, RCD and socket all need to be changed. At which point there’s probably not much difference in a proper EVSE setup.
 

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Discussion Starter #11
Of course you should get an electrician to inspect it and tell him what you intend to use if for.

It’s very likely that he may say the wiring, RCD and socket all need to be changed. At which point there’s probably not much difference in a proper EVSE setup.
My sparkie has come back stating that it should be fine so long as it's no more than 13amp. He wired this place 3 years ago and it's all new wiring & fittings etc. I was aiming to use an extension reel from an external 13amp socket in the yard to the front and plug in from that? Will that work?
 

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Discussion Starter #13
Try it. Hopefully the voltage drop won't be too much.

Keep an eye on the plug that it doesn't get too warm.
Cheers. You know you said in an earlier post (above) that to turn down the Tesla amps to 8 - How do you do this?

Again if I'm going to plug in a 20m standard extension reel into the external 13 amp socket will this be OK?

Many thanks.
 

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Cheers. You know you said in an earlier post (above) that to turn down the Tesla amps to 8 - How do you do this?

Again if I'm going to plug in a 20m standard extension reel into the external 13 amp socket will this be OK?

Many thanks.
If you go into the charging screen, there's an option to set the Amps once plugged in.

In terms of a 20m extension, I don't know as I've never done it. The general advice is not to do it or keep the extension short.

If you have to do it, I'd go and get a heavy duty extension that's actually rated to a continuous 10 amps or more.
 

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Cheers. You know you said in an earlier post (above) that to turn down the Tesla amps to 8 - How do you do this?

Again if I'm going to plug in a 20m standard extension reel into the external 13 amp socket will this be OK?

Many thanks.
If you must charge using a 13A socket and extension lead at least use a decent lead that has a waterproof socket and preferably a RCD. A drum is rarely a good idea unless you fully unwind it and ensure it is excellent quality. The one I use with my jet wash I certainly wouldn't use to charge a car for several hours.


Officially extension leads are not allowed for two reasons (a) it keeps potentially unprotected cable between plug and EVSE short (b) There is less risk of EVSE being submerged in water - they are NOT waterproof.

Presumably if you arrive home with low charge you don't might waiting many hours to go out again? Or do you have another car you can use?
 

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Discussion Starter #16
If you must charge using a 13A socket and extension lead at least use a decent lead that has a waterproof socket and preferably a RCD. A drum is rarely a good idea unless you fully unwind it and ensure it is excellent quality. The one I use with my jet wash I certainly wouldn't use to charge a car for several hours.


Officially extension leads are not allowed for two reasons (a) it keeps potentially unprotected cable between plug and EVSE short (b) There is no risk of EVSE being submerged in water - they are NOT waterproof.

Presumably if you arrive home with low charge you don't might waiting many hours to go out again? Or do you have another car you can use?
Thanks. Yes it has to travel from the external 13 amp socket position across the yard by approx 20m. There is use of another car but reading through and judging by all of the above posts seems to me that it's best to spend the money & get a wall charger.

Tesla have just emailed. suggesting could be mid November so I need to get my skates on!
 

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Actually just realised that the quote I've had includes for the £350 OLEV and excludes VAT so in total his quote is £2,566.80 !!!! For a Rolec.
 

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Actually just realised that the quote I've had includes for the £350 OLEV and excludes VAT so in total his quote is £2,566.80 !!!! For a Rolec.
You need to get another quote. If you try a larger electrical contractor they will be able to use lower cost labour for some of the work. People often think the local one-man-band sparky is cheaper, but it doesn't always work that way especially as most are registered for VAT too.

Using a quality extension lead and Tesla UMC is OK as a temporary measure while you sort out charging point.
 
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Actually just realised that the quote I've had includes for the £350 OLEV and excludes VAT so in total his quote is £2,566.80 !!!! For a Rolec.
Do you have a breakdown of the costs? What’s the cost of running the cable out 20 metres? This might be what’s driving the cost.

In which case you can get out there with a shovel one weekend. :)
 

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As per the previous posts keep it at 8amps max. That’s still 2kWh continuous for 20 hours or more. You don’t want to find the weaknesses in your electrical circuit at 3am with the smoke alarm blaring.
 
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