Solutions for two ev chargers

[DansDan]

Hi,

I'm looking into solutions for someone wanting potentially two ev chargers and wondered if anyone here has had experience with this.

They potentially, depending on price would like two ev chargers fitting to the house facing the drive, one either side of the front door but only for charging one vehicle at a time currently.

It seems the options are...

1. Install two chargers on two seperate circuits, assuming the supply can cope with the demand if both were to be used at some point in the future at the same time.

2. Install one circuit to a switch over device that can be switched from A - B - Off so that only one charger can be used at a time. My only concern with this is I know connectivity can be an issue and start up/sync times when a unit is powered on/off for example.

3. From what I can gather, some ev chargers are capable of being daisy chained on the same circuit and, if two cars were to be plugged in, they are smart enough to load balance between themselves, reducing the charge rate. Can anyone recommend a brand that does this in the UK or have you fitted them?

Looking forward to your input!

Thanks

 

[MoserV8]

Hi,

I'm looking into solutions for someone wanting potentially two ev chargers and wondered if anyone here has had experience with this.

They potentially, depending on price would like two ev chargers fitting to the house facing the drive, one either side of the front door but only for charging one vehicle at a time currently.

It seems the options are...

1. Install two chargers on two seperate circuits, assuming the supply can cope with the demand if both were to be used at some point in the future at the same time.

2. Install one circuit to a switch over device that can be switched from A - B - Off so that only one charger can be used at a time. My only concern with this is I know connectivity can be an issue and start up/sync times when a unit is powered on/off for example.

3. From what I can gather, some ev chargers are capable of being daisy chained on the same circuit and, if two cars were to be plugged in, they are smart enough to load balance between themselves, reducing the charge rate. Can anyone recommend a brand that does this in the UK or have you fitted them?

Looking forward to your input!

Thanks

We could have really done with a little more Info to be honest , the whole Subject of EV Chargers & Suitability is without doubt a highly specialised subject - ive seen lots of very misguided information, yes and some on YouTube as well! If your customer is only wanting to charge 1 vehicle at a time why would they want 2 chargers? What supply does your customer have? For Example a Volkswagen ID4 will charge at 11KV - now then, that means roughly the charging circuit will be drawing 48Amps for the entirety of the charging cycle. Few houses have the capacity for this with running other appliances, therefore most would have to make do with a 7KW Charging Point - which on my last customer, was 31.6 Amps continuously , at a charging rate of 18 Miles per Hour, an overnight charge for them of 8 hours - would not fully charge their car. To simplify this you need to know what distances they cover in their vehicles each day, why they actually need to chargers when they are only going to charge 1 car? What the incoming supply is rated at, What their current electrical demand is in the evening, because at the time people come home and plop their car on charge, is also the time, the showers are run, ovens are put on, heating etc etc You then need to workout what surplus you have and size the charger accordingly, allowing as well for the correct protection and specialist earthing when you instal it.

 

[littlespark]

I’ve had the same conversation with a customer.
Wanted two outlets. (He doesn’t get his first EV until April) and the choices are very limited.

There is one on the market I know of which is 1 unit, 2 outlets and you program which car is charging at what time. Which if I remember is a Project Ev unit.

There was another, whose name escapes me, which is advertised as “up to three units on one fuse” Meaning the units must talk to each other to balance the load to not exceed the maximum rating of the fuse.


Because of the lack of choice, my customer decided for just one charge point, and he would choose which car to plug in.

Most, if not all charge points now come with load management, to protect the main fuse.

 

[PeakSteve]

I've done this with 2 Zappis (the customer already had one and wanted another).
I upgraded the existing SWA supply cable's MCB as far as I could (45A I vaguely remember) and installed a small outdoor consumer unit (each charge point MUST have its own over-current protection) with Main switch and 2 x B32 MCBs (the Zappis dont want additional RCD-protection). Zs was sufficiently low to comply.
I connected 1 Zappi to each MCB, and fitted the Master Zappi's current monitoring clamp on the Distribution Circuit supply and set it to limit to 45A (as well as the Zappi's main monitoring on the household's 100A supply). In the Zappi set-up you can then assign either a sharing of available power, or a priority for one over the other.

So in this case, if the household total requirement exceeded 100A, OR if the current in the Distribution Circuit exceeded 45A, the Zappis would reduce power accordingly. {As required, firstly application to the DNO for 100A was made and permitted]

I'm fairly sure some of the better makes will have similar facilities.
And if it all goes wrong, the 45A MCB would trip anyway!!!