Second charge plug to EVSE

...Ghost...

Looking for some view points.

I own a 3.6 and 6.6 Leaf. On occasion, I need to charge both cars overnight. Both timers are set for after midnight. My EVSE is a 7kWh with a 13Amp domestic socket built in.

We have a priority switch for the electric shower. I put gravel down in the garden, so we now park both car in the garden and I want to move the EVSE to the other side of the main entrance, because the charge cable is a trip hazard when both cars need to be plugged in.

We have not yet availed of the €600 grant toward an EVSE. The existing one was out of my pocket. So I was was thinking of two options.

a) Leave the existing EVSE where it is and have a 3.6 rated (or lower) EVSE installed on the other side of the door. I am concerned I may limit myself to a standard 10Amp charge rate here, because a full 3.6kWh might be too much when combined with the 6.6kWh. I would prefer to avoid using the granny charger.

b) Move the existing EVSE to the other side of the door and install a second charge plug (if possible) to allow me to plug both cars in. My thinking here is that the cars will split the 6.6kWh from the same EVSE and each car will only draw a max of 3.3kWh, but I could be wrong. We have 7 or hours of charging each night and usually have need 15kWh of charge per car.

I wanted to come here first before going any further and calling in an electrician. I think €600 will cover either scenario. Thank you for your help.

KCross

The pedestal type charge points have two type 2 sockets but they are generally many multiples in price to what you have.

I don’t think you’ll find a reasonably priced product for your option b

With electric shower, priority switch and two EVs what you really need is a load sensing EVSE so that’s a Zappi or a Garo. They will dynamically ramp up/down depending on your whole house load. That’s the direction you need to be looking in.

...Ghost...

KCross wrote: »

I don’t think you’ll find a reasonably priced product for your option b

I would like to continue to use the EVSE I have. Is it possible to retrofit a second charge plug to the same unit? If the unit is limited to 7kWh, the cars could not draw more than what is available from the EVSE.

The idea came to mind when I was told that I needed a 7kWh EVSE for the 6.6 Leaf, because the car would only pull what was available from the EVSE.

Something like this => https://evonestop.co.uk/collections/spare-components/products/type-1-j1772-plug-32amp-7-2kw

KCross

...Ghost... wrote: »

I would like to continue to use the EVSE I have. Is it possible to retrofit a second charge plug to the same unit? If the unit is limited to 7kWh, the cars could not draw more than what is available from the EVSE.

The idea came to mind when I was told that I needed a 7kWh EVSE for the 6.6 Leaf, because the car would only pull what was available from the EVSE.

Something like this => https://evonestop.co.uk/collections/spare-components/products/type-1-j1772-plug-32amp-7-2kw

AFAIK, its not possible (financially at least) to add an extra socket to your existing EVSE. The smarts to allow it load share are not inside the box.

My point, though, is that you dont need to throw away the existing one.

What you do is keep using the existing EVSE as is (or move it if you want) but then add a second EVSE which has load limiting capability so that both charge points can charge at 7kW as needed but if you have both cars plugged in the second charge point will ramp up/down its rate to ensure you dont blow any fuse.

You get ultimate flexibility that way.

n97 mini

Your 7.2Kw EVSE signals via the pilot line that it can provide 7.2. If you fit a second plug to the existing EVSE your 6.6 Leaf will see the 7.2 signal and attempt to draw 6.6. Simultaneously the 3.3 Leaf will draw 3.3, so no adding a second cable to your existing EVSE will work. It's also dangerous as when one plug is live, they're both live.

You do have a solution to simultaneously charge both as you currently are: plug the 3.3 Leaf into the EVSE, where it will only draw 3.3, and plug the 6.6 via the granny cable into the 13a socket. It will only draw 2.2 on the granny cable.

Alternatively if you do want to install a second EVSE you could do so on the same line. It must be a 3.6 though, and if charging both cars simultaneously the 6.6 must be plugged into that.

_dof_

You could install a Zappi on a new circuit from the consumer unit, not going through the priority switch.
Set the load limit on the Zappi to keep the whole house draw below your main fuse current, lets say 60A.
When the shower is on, and the priority switch disconnects the existing EVSE, but the Zappi would still charge the other car at some reduced current since it's running at the same time as the shower.

When the shower is not on, both cars can charge at full rate, since one would draw <16A and the other would draw <32A. Even in the future when you have 2 cars capable of 7kW charging, then the existing EVSE would charge one car at 32A and the Zappi would charge the other at 28A (or a bit less depending on whatever else is drawing current during the night)

...Ghost...

It sounds like a Zappi is the answer with the current EVSE. Thank you all for your valuable input. Perhaps the short term solution is to install an outdoor socket where the second EVSE will eventually go. This will remove the trip hazard.

KCross

...Ghost... wrote: »

It sounds like a Zappi is the answer with the current EVSE. Thank you all for your valuable input.

Zappi or Garo.

Alkers

...Ghost... wrote:

My EVSE is a 7kWh with a 13Amp domestic socket built in.

What model is it? After something similar

n97 mini

Simona1986 wrote: »

What model is it? After something similar

Rolec Wallpod "Multimode" have built in sockets.

Alternatively you could do what I did: the mains comes out through the wall into the back of an outdoor socket, and the charge point is wired into the the socket. In typical installations the cable comes out through the wall into the back of a junction box, and the charge point is wired into that. Only cost a few quid extra to have a socket, and it means I can install whatever charge point I want then after that.

EDIT: not a great photo, but you get the idea. The socket is the lower box. I've since replaced the Chargemaster with an OpenEVSE.

Alkers

n97 mini wrote:

Alternatively you could do what I did: the mains comes out through the wall into the back of an outdoor socket, and the charge point is wired into the the socket. In typical installations the cable comes out through the wall into the back of a junction box, and the charge point is wired into that. Only cost a few quid extra to have a socket, and it means I can install whatever charge point I want then after that.

Thanks for that, is there any issue with using the socket and charger at the same time?

n97 mini

Simona1986 wrote: »

Thanks for that, is there any issue with using the socket and charger at the same time?

No, as the RCBO is rated at 40 amps. If the Ampera is charging it only uses 16 amps, so there's plenty of headroom. Even with the Leaf, which charged at 32 amps, there's still plenty to run a hedge trimmer, lawn mower etc.

...Ghost...

Simona1986 wrote: »

What model is it? After something similar

https://evonestop.co.uk/collections/wall-mounted-chargers/products/wallpod-ev-multi-mode-type-2-tethered-cable-5m



I am not sure where I got mine. May have been ev one stop in the UK. It's a nicer unit than some out there.