10mm² is now the norme for this purpose. It’s the continuous high load thing as opposed to the rated capacity.
A lot of the 3 position HC./HP contactors (which are designed for use by water heaters) are rated 25A max, so no. However you can get simple contactors up to almost any rating.
If you’re talking about putting in a contactor for a 7kW EV charge controller then you’re wasting time & money. Any decent charger can be programmed &/or can be wired to respond to the téléinfo port in the Linky i.e. délestage/load shedding. Failing that most EVs have a charge timer built in which you could use.
For all the reasons that others have already mentioned it’s not a good idea to have potentially live wiring in a panel that appears to be isolated. However, all distribution boards require tools to access inside so are considered to only be opened by competent people. Even then labelling would be polite!
I did once wire several small gîtes onto one supply that used simple contactors (triggered by the Linky C1/C2 contacts) at a central distribution board to trigger further HC/HP contactors in the individual installations i.e. the main contactors were just a dry contacts for the trigger circuits that were fed back there from each gîte.
Thanks Badger - I shall run a length of 10mm as you suggest. It is a pig of a job to pull cable under the house, so if I am going to make a dedicated EV circuit, then I might as well future proof it. I am sure my needs will be served by a granny chsrger on HC though. Ajob for Monday. The car should be here next week.
If you are using the Granny charger , you really don’t want to restrict yourself to Night rate .you will want it on all evening to morning . Assuming 16KWhr per 100KM and a 2 KW charger you would need 10 hours..maybe more in winter when you need lights and a warm car … Charging is not 100% efficient.
See how you get on with the granny charger on HC for the first few months and then decide if you need anything more substantial- you might be pleasantly surprised.
Considering the hassle of pulling through a 10mm SWA cable on my home and establishing a new granny socket cable to an exterior socket on a dedicated run, there isn’t much difference, certainly something I am considering at the next year’s visit.
I am sure the time will come when I dhall resent paying the price to fill up my other ‘fun’ cars to the point the EV will take over and I will need a 7kW charger - but when the time comes, with the now 10mm (thanks again Badger) cable in place, it will be an easy/quick change…
Good choice. Some pain now that will be worth it in the long run.
It’s certainly worth a try, especially if you have a rapid charger not too far away so you can quickly top up in the event of unforeseen need.
As I’ve already said, you can use the car 's inbuilt programming to charge on HC only - check your allocated time(s) on your electricity bill.
However - TOP TIP - don’t forget to overide the car’s timer if you ever use a public AC Level 2 charger. As at home on your granny charger it will wait until your programmed HC period starts i.e. you could leave it for 4 hours & come back to no increase in charge
N.B. Inbuilt timers do not effect DC rapid charging in any way.
It might be that plastic prices have soared …If I were doing that task I would by preferences get a gain 25 mm diameter ..and put in my 3 wires . And then pull the lot as a Single run from the distribution board to the target location .. . .The alternative is armoured 3 core cable which will be more rigid. . Both wire costs are similar. Of course without a site inspection no decision can be made .So I would leave that decision
You cannot use single core outdoors, (underground) it has it’s own classification cable. I did years ago before I found out but last summer replaced it all with compliant cable.
Use of single conductors inside gaine is only permissable outdoors above ground. If buried one must use double insulated R2V cable inside a red gaine at 500m depth minimum.
Also any gaine outdoors must be UV proof e.g. rigid IRL is OK but flexible ICTA is not (however UV proof flexible gaines are available, at a price). Gaines carrying single insulated conductors must also be sealed against water ingress & designed to drain if they do get water inside.
All in all using double insulated cable is a lot simpler, either surface clipped or ‘style Metro’ in open IRL gaine.
I’d need to check my tables but I suspect that 3 x 10mm² singles probably exceeds the one third maximum fill capacity of 25mm diameter ICTA, & possibly that of IRL too.
I appreciate too that the actual connection of a 7kW charger needs someone with the right paper - we had this conversation many years ago when Gites de France advised it a good idea to give visitors a car charger that I did not pursue for this reason and cost - well done as I have only had about three EVs in all this time, who each have said car charging is not expected in the same way that a petrol pump is not expected - each one has been more than happy to plug in whilst shopping…
But I diverse. I hear what you alll say about inbuilt timers, but honestly, I have real hate relationship with any timer - even a basic egg timer seems to go wrong with me! I like the re-assuring thump from the board at 21:00… so I will go ahead to install an HC array - now my question:
It would work but in my view is totally pointless.
If you just rely on the HC signal you are tied to the times it starts & then there are usually 8 hours of uninterrupted use*, which could (if the EV needed a lot of charge) preclude you from running other things in the HC period (dish washer, washing machine, some heating…) as, theoretically, your EV could hog 7kVA of your subscription, which might only be 9kVA, or maximum of 12kVA on monophasé.
As an aside one of my EVs draws 6,6kW in Level 2 mode & I’ve only got a 9VA subscription. We run a dishwasher, washing machine & some background heating during HC & due to allocating time slots carefully we’ve never exceeded our maximum load.
Using the EVs own timer, or the Level 2 charger’s programming, means you could just charge it at the start of the HC period & (maybe up to 5 hours, giving you 30-35kWh) then time other devices to use the remaining 3 hours.
Another factor to consider is space in your distribution board. A Level 2 charger will require at least 3 modules of space (2 for the Type F or A interdiff, 1 for a 40A disjoncteur) & your 40A contactor then requires 2 more modules & involves more connections to potentially go bad at some point.
*Some areas have 6 hours overnight & 2 at lunchtime, & there is a move to offer this split more widely so that people can use cheaper power in the daytime to make use of excessive solar in the grid.
Adam… Most Level 2 charge points will have built in timing applications ..The Charge point is basically a microcomputer with a few power contactors added ,so including sophisticated timing and communications is basically free to implement on Wi F . So if I have to , I plug in the EV during day or evening and charges at 1.6KW , but once 11pm strikes, it immediately moves to 7.3KW ,until the car has charged ..or until 8am. when it reverts back. .There is also a facility in most EVs to defer charging until set times or days ..but that can cause glitches …If you plug into a public charger it might do nothing until the preset time is reached ..Of course a button pushed on the charge point or the mobile phone application would give the 7.3KW , at any time requested .
Basically I am saying that for a Level2 , you don’t need an external HP/HC as the unit is genuinely set and forget ..it will remember and even were there power failures etc . once WiFi is re established the clock will adjust. And with Level 1 or Granny lead , you usually will need an extended charge time anyway.. I see that Badger has basically said the same thing while I was writing this
I appreciate that I am jumping all around the place, without even taken delivery of the car yet! So, I will hold fire and go with my idea of the granny charger to see what it gives me and with a bit of gained knowledge, then look to the future in more detail. In the meantimes, I’ll still run the 10mm cable tomorrow but just a straight connection on a 16A MCB. I can physically plug in at 9pm…
Your above interests me - I have a 15kVA subscription…
Thanks. See above! I shall back off, play with the basic charger and maybe come back in a few weeks for a more advanced lesson after I have investigated what timer the car offers.
You will have a triphasé supply then. This creates some potential problems.
If you are buying an EV with monophasé Level 2 charging then you will have to restrict your EV charge rate to a maximum of 25A/5kVA unless you want to trip the whole supply due to overload of one phase (& assuming nothing else heavy uses that phase, which is unlikely unless your house was badly wired by someone who didn’t balance things across all phases nicely).
Not all Level 2 chargers will do that so if you need/want the full 7kW you’ll need to increase your supply size to at least 24kVA, with a consequent increase in standing charge.
If you are buying an EV with triphasé charging then you’ll be able to use an 11kW charger, the load of which will be split across all your phases i.e. approx. 4kW per phase. Theoretically this would avoid a supply size increase, but depending on what else you are running you may still need to ask for more.
According to Energie .. 15KW is the maximum value at which single phase is delivered ..and by 18KW it must be 3 phase supply . Moreover they they state that depending on circumstances any premises from 9KW tariff upwards can opt or be recommended to go 3 phase … . .Whether you see this as fortunate or not depends on your circumstances … 3 phase fittings and appliances are more expensive , but then more trouble free … 3 phase motors in heat pumps or milking Parlours etc for instance are smoother , and a EV charge point would be capable of 11KW . Incidently every modern EV in Europe ..with the possible exception of the AMI will take single or 3 phase in the .connector.
- each one has been more than happy to plug in whilst shopping…