Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Unable to have home charger installed?

This site may earn commission on affiliate links.
Hey, I’m new to the forum but joined as I’ve run into a problem.
Ive recently bought a used Model S (85 with dual charge). I live in the country with no gas so cooker, shower etc runs on electric. When the firm i contacted to install the home charger came round they said it would be next to impossible or very costly to install on my existing system as I’m already using most of my 100A allowances.
They said I had the following options,
1. Install on the existing system but run a cable back to the meter that would attenuate and drop what the car was taking if other appliances kicked in so it didn’t go over (they thought this would be expensive as its a considerable distance from the house to meter and house to drive)
2. Install solar to increase Amp capacity of house (I’m guessing £7-10k)
3. Get a new electric supply fitted just for the car (this is the one they recommended). I spoke to my local supplier and I’m guessing this would come in at £6-7k
4. Continue to run off my 10A granny charger which I’m currently doing and on the whole hasn’t cause me any problems.

Just wondering if any other users ran into similar problems?
 
More solar is always good. :)

If all you've got on the mains is 100A and you have some other appliances that are pretty hungry, I could easily see this happening, especially if you're asking them to install the maximum hardwired EVSE (32A x 3 phase in the UK, right?)

I don't know how much spare capacity you have on your board, or what the code is there, but another fairly inexpensive option might be to install the wall connector on a smaller circuit/breaker and limit it to a draw that's within your requirements.
 
  • Helpful
Reactions: GSP
@Saghost limit in the Tesla? I think the installers said they wouldn’t do that in case I didn’t limit and it caused a fire.

No, in the wall connector, a permanent limit that matches the circuit it's on. I don't know that much about the EU version, but in the US version there's a sixteen position rotary switch inside the housing which is set when you install the device, adjustable from 6A to 80A (US is single phase) plus a "slave" position that allows it to share a circuit with a second Wall Connector.

I'm sure the EU version has a similar setting, though presumably not exactly identical.
 
  • Informative
Reactions: GSP
The EU Wall Connector manual is here. It supports almost any kind of grid connection that exists in the EU. 230VAC single phase with Neutral (1 leg Wye), 400VAC 3-phase with neutral (Wye), 230VAC single phase without neutral (1 leg Delta), and 230VAC 3-phase without neutral (Delta).

It says:
The Wall Connector has an internal rotary switch that allows you to adjust its operating current (refer to Set the Operating Current on page 19). The circuit breaker should be rated for the continuous current of: 6, 8, 10, 13, 16, 20, 25, or 32A.

So, it's likely that you could get a little bit more than the 10 amps that the 3-prong UK "granny charger" will get you. I would see if the electrician would go for 16 amps on your existing service.
 
  • Informative
Reactions: GSP
If you've got room on your panel for a circuit, I'm not really seeing the issue. You don't run your stove/oven, water heater, clothes dryer, etc continuously. I can't imagine you're using close to 100A at any given moment, much less at night.

*shrugs*
 
Another variant on (3) is to get your existing supply upgraded to 3-phase. Probably costs similar or less than a new supply and better in that you end up with one meter, one bill (hence one monthly charge or however that's factored into your tariff), and as a bonus you can charge the car faster (11kW vs 7kW max on single phase). But it's inevitably expensive.

It's unclear how getting solar would be of any help (other than being a good thing in its own right), since you will normally want to charge your car at night when the solar isn't generating.

If you don't want the expense of a supply upgrade, your option (1) should really be quite satisfactory - most of the time you will be charging at night when all these other appliances are not in use, so the automatic cut-back on charge rate would only come in to play quite rarely. If it really needs a long cable run, then it's not the cost of the cable but the cost of digging the hole to lay it in that's significant, so you could reduce the cost by digging it yourself (or whoever normally digs your garden...). I don't quite understand the layout from your description - you say it's a long run from the meter to the house and from the house to the car parking location - suggesting you have the meter separate from the house (in an outhouse or similar)? Unless there are significant loads in that outhouse, there's no need for the measuring sensor for the power control to be actually at the meter: since you are aiming to balance the load of the house and the car charging, the sensor could equally be at the point where the power enters the house, or at the consumer unit etc. Or if the geometry suits, a feed direct from where the meter is to the car charging point and nothing needs to be installed in the house.

I would advise you to do SOMETHING rather than just continuing to use your UMC on a 13A socket. Doing that over long periods is likely to cause wear and tear on the 13A socket at least; particularly if this is outdoors. Also, if it ever fails (the socket or the UMC) you then haven't got a backup means of charging. If you can't justify the cost of 32A charging, then at least a 16A chargepoint is probably possible, giving more satisfactory charging and allowing you to leave the UMC in the car for use in case of emergency - whether at home or on the road.
 
  • Helpful
Reactions: GSP
Another variation: although a 'smart' chargepoint that can control the power drawn by the car is the best option, there's relatively few units with that capability. There are other options with ordinary electrical switchgear, for example:

http://www.meteorelectrical.com/dis...ro-priority-shower-board-choose-priority.html

That unit is designed for people in your situation who want to add another electric shower but don't have sufficient supply capacity - it ensures you can't use both showers at the same time. It could equally be used to ensure you can't use the shower (or some other load) at the same time as the car is charging.
 
If you've got room on your panel for a circuit, I'm not really seeing the issue. You don't run your stove/oven, water heater, clothes dryer, etc continuously. I can't imagine you're using close to 100A at any given moment, much less at night.

*shrugs*
As long as you do the work yourself, I suppose that's an option. But I wonder if a licensed electrician in the UK would.
 
Thanks guys

I’m sure I wouldn’t overuse the 100A but the installer said they wouldn’t do the installation as they cant put something in that i could potentially overload and cause a fire.
My meter is on a neighbours property (long story) so to run a cable to or from it would involve digging up his drive and land so i dont think that could happen.
I’m just trying to find an option that doesnt cost £4-8k as opposed to the £300-£600 i was expecting.

The units that attenuate themselves or i can drop down the load on the unit (ideally i could change this dependent on what else was running time of day etc?)
 
The other alternative is the eVolt with a Beon device. This is a charge point which is still eligible for the OLEV grant however it is particularly useful for properties with demand issues. The Beon device is installed around your incoming meter tails and monitors the usage. If your usage goes over your supply capacity it will reduce the power going to the charge point to avoid blowing your main fuse. It is available from about £449 + VAT from most charge point installers.
 
As long as you do the work yourself, I suppose that's an option. But I wonder if a licensed electrician in the UK would.

Panels are typically "overloaded." I sure have FAR more circuit allowance than 200A...including the 100A circuit that goes to the sub-panel in my garage.

Panels are designed to trip in the event of overloading. I obviously don't know how much his appliances are actually using...I simply stated that having usable over-capacity on the panel doesn't mean there is an issue. He made it sound like the electrician was trying to upsell him...as they are wont to do.
 
I’m already using most of my 100A allowances

I have 100AMP supply and a long underground cable that is skinny and consequence of possible low voltage at high load.

We cook electric, nice modern ovens and hobs, but the hob is induction, has "Mega Boost" on all the rings, and has a supply cable that resembles a solid copper busbar! We have two electric ovens too, and loads of computers on 24/7 sucking up some background kws (which I would like to do something about ... but that's a separate story).

I don't have second-charger, so clearly you could use more Umph than I can, but I get 20 MPH charge (forgotten how many AMPs that is - 16AMPs perhaps). If your cooker is an Electric night-storage Aga type thing I suppose that could be a problem.

So "on paper" you might have a problem, but I wonder if you actually will in practice.

I like the suggestions of equipment that will save-you-from-yourself and automatically reduce load / take action. It begs the question, in my mind, why your Sparky did not SUGGEST that. I NEVER get that sort of doom-and-gloom from my Sparky. He tells me what the REGS are, that we have a problem, and proposes options to work around that (no doubt all will cost me money!!, its just a question of me making a choice). He isn't up for doing anything illegal, but he always has a solution

I am very doubtful that installing 3-phase is anything other than massively expensive due to Electric Company monopoly. And that's not including your complicate cabling situation. I want my Electric Utility to install a better cable that gives me the service that they have to guarantee (i.e. to stay within voltage drop tolerance), I am perfectly happy to dig the trench at my cost, but they say they won't because they say I need 3-Phase, which they are quite happy to charge me for (and outrageous price)

my advice: Change your Sparky

Worth thinking about how long you need to be able to charge overnight. It will be a rare day that you come home at 0%, it is pretty rare for me to come home at 10% - if I'm on a journey I tend to want a little more "safety margin" than that, and its also rare for me to charge to 100% - and even more rare!! for me to charge from <20% to 100%. So "most nights" I only need to charge a max of 70%. At 20MPH charging rate that's 9-hours for me, and most of the time 7-hours will do. I just mention this because you are new to it, and perhaps don;t have a problem at 16AMP. Your use-case may be very different and of course you may indeed need fast-charge. Also frustrating to have that ability fitted to the car but not use it ...

I have hardly used my home charger as it is more convenient for me to charge at work

I have that "convenience" too <fx:whistles> :) but looking at my Logs I actually charge more at home than work - probably the occasional mid-week long business trip that needs an overnight charge to get back to work next day, and all the weekend to-ing and fro-ing