After a couple of years of enjoying our first i-Miev, we just bought our second one. So, now we need to charge them, hopefully at the same time.
I've mostly been using the 8-amp option on the charger, which works great overnight. With a second car, the easiest option seems to be to just plug both of them into the same outlet--which would draw 16 amps. But, if I recall correctly, most houses have 15-amp circuits--although I've heard that newer houses (ours was built in 2000), have 20-amp wiring in the walls.
If you are trying to use the same outlet, first check the electrical panel to determine which breaker controls that outlet and determine if there are any other outlets on that circuit.
Then determine if it is a 15-Amp or 20-Amp breaker?
lf 20, and there are no other outlets or possible loads on that branch, then two 8-Amp EVSSE units at the same time would be hitting the max capacity rating for the circuit (80% of 20A= 16A).
If it's a 15, then two at the same time would exceed the max rating (80% of 15A = 12A).
Charging two cars EVen with the 8 amp EVSEs on a single circuit would be running a 20 amp circuit at it's absolute maximum (derate by 20% for a continuous load). My household now has two electric daily drivers (we added a 2016 Kia SOUL EV), and though I had fretted about coming up with two L2 EVSE or a load-sharing dual-headed EVSE, it's working just fine with one 32 amp L2 and one 12 amp L1 EVSE. Our vehicle usage is different each day, but whichever car has the greater need takes L2 and ensures that the other car gets plugged in on L1. Three months now without a car coming up short on charge.
If your circuit has no other loads . . . . and if the breaker is a 20 amp one . . . . then that means for sure the wire in the wall is 12 gauge and running them both on the same outlet really poses no problem - Both the breaker and the wire can handle more than 16 amps, but for safety's sake, we always de-rate a 20 amp circuit by 20% just to ensure a safe margin for continuous use . . . . and charging cars is a continuous use - Even if you were drawing 18 amps instead of 16, both the wire and the breaker would handle it, but it's not recommended for a use like this. I would advise at the very least you replace that outlet with a quality, hospital grade outlet before you begin using it to support the 16 amp load
If you do decide to install another outlet, I would advise you to make it a 240 volt outlet, assuming you have room in your panel for a new double breaker, with either 20 or 30 amp breakers - 20 for 12 gauge wire, 30 for 10 gauge wire. That opens up many other charging possibilities, both now and in the future
Don
2012 iMiEV SE Premium, White
2012 iMiEV SE Premium, Raspberry Metallic
2012 iMiEV SE, White
2021 Volkswagen ID.4 Glacier White Metallic
2014 Ford Transit Connect XLT SWB wagon
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I think that I'm going to add a Clipper Creek L2 charger. It'll make it possible to pre-heat one of the cars in the morning, as well as getting a faster charge when needed. I was hoping that I didn't need to call an electrician, but I think that this will be the most flexible and best approach.
IF that is the ONLY outlet on that breaker, AND it has 12ga wiring,
an electrician could easily convert it to 240V, 20A(derated to 16A) using the existing 12ga wiring.
The white neutral wire would be marked at each end with red tape and labeled HOT.
At max charge rate our Maeve pulls about 13.5A, so well within the 16A limit.
IF that is the ONLY outlet on that breaker, AND it has 12ga wiring,
an electrician could easily convert it to 240V, 20A(derated to 16A) using the existing 12ga wiring.
The white neutral wire would be marked at each end with red tape and labeled HOT.
At max charge rate our Maeve pulls about 13.5A, so well within the 16A limit.
Also, you can have your OEM Panasonic EVSE 'upgraded' to 12 amps and it will do 12 amps on either 120 volts L1 or on 240 volts L2. Since the car uses less than 14 amps on L2, an upgraded EVSE will charge at better than 90% of the maximum possible . . . . and, if you need to use L1, it will provide 12 amps instead of the usual 8, which is a 50% increase. Handy even if you do eventually buy some other L2 EVSE. Check out www.evseupgrade.com - Lots of us have done business with them over the years
I have 5 different EVSE's, but I still use my upgraded Panasonic every single day
Don
2012 iMiEV SE Premium, White
2012 iMiEV SE Premium, Raspberry Metallic
2012 iMiEV SE, White
2021 Volkswagen ID.4 Glacier White Metallic
2014 Ford Transit Connect XLT SWB wagon
2006 Itasca Navion Sprinter Motor Home