Home L2 Charging: 40A versus 48A

[Windsurf]

I recently purchased a ChargePoint Home Flex with a NEMA 6-50 plug at list price. NEMA 14-50 model is out of stock in most places, delayed shipping and costing more.

Anyway, I'm torn between hardwire install with 240V/48A supply/60A Breaker (estimated range per hour of 36 miles) and plug-install with 240V/40A supply/50A Breaker (estimated range per hour of 30 miles). Would appreciate hearing from owners who have one of the 40A or 48A setups (doesn't have to be a ChargePoint EVSE) with their pros and cons. My chosen electrician has quoted $150 difference between hardwire and plug install; not enough to sway me one way or another; wire-run of 35 feet from breaker panel. I plan to carry the Ford-supplied EVSE w/cables in my frunk as I know the NEMA 14-50 plug is more prevalent across the country.

Thanks for any input you provide!

I have both one hardwire, one 14-50. 2 EV. Difference in cost from my electrician wasn't $150. I put in the plug because I use it for other 240v tools in my garage. Will say that it is nice to get the faster charge when I get home with a low charge. I do notice it. But if you want the 240 plug for other things it's more convenient.

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[ridgebackpilot]

I don't have an EV yet but I'm in the market for one. Also, I have s solar system too (10 kW panels, 30kWh storage, 9kW continuous power from my inverter). One thing about a higher amp charger is the demand it puts on the inverter. A 240V/32A charger demands 7.7kW -- meaning my 9kW inverter can supply that plus 1.3kW more (for the house's other electrical needs) before pulling from the grid. A 240V/48A charger will pull 11.5 kW -- I'll automatically pull at least 2.5kW from the grid (plus whatever else the house needs at that time).

I'm planning to upgrade my solar system (including doubling my inverter) to reduce this issue. I bring it up because it might be best to have two charger outlets: a lower amperage charger and a higher one (more liable to pull from the grid, but if you need the power you need it). If you come home near empty and have a long trip soon -- use the higher amperage one. If you come home with 3/4th's of a "tank" and have nothing but a 40 mile round trip commute planned the next day, user the lower amperage one (less likely to pull from the grid).

And that's not even getting into if your solar inverter has a "smart load" feature or something like that where it'll power a certain circuit panel only if your home batteries are charged to at least a certain percentage (more then enough power to make it through the night on stored solar power, might as well use some of that for charging the EV, but only as long as the home batteries are charged above that threshold).

@Tell It Right Do you have NEM and EV rates from your power provider in Alabama? What that allows me to do is sell my solar power back to the grid during peak and mid-peak hours, and charge my EVs from the grid during off-peak hours only.

My solar system is smaller than yours, so while I could charge the EVs directly during the day, I find it less expensive to offset my use of the grid during peak times of day. The Powerwalls allow me to power my house during peak hours, but they wouldn't last long if I charged the EVs during that time. So I simply send solar power to the grid during the day and charge the EVs overnight to take advantage of off-peak pricing.

 

[Tell It Right]

Sorry for the late reply. My power company doesn't do net metering. And we do have EV rates, but we have to pay a higher monthly flat rate to participate in it.

 

[Logal727]

I’m perfectly happy with my Grizzl-E set to 32A, never have been in a situation where that wasn’t enough.

 

[dtbaker61]

I’m perfectly happy with my Grizzl-E set to 32A, never have been in a situation where that wasn’t enough.

exactly....
so the included mobile charger plugged into a standard 14-50 outlet is 'enough'

there is literally no need to buy a dedicated charger or hardwire.... just use the included mobile charger.

 

[Logal727]

exactly....
so the included mobile charger plugged into a standard 14-50 outlet is 'enough'

there is literally no need to buy a dedicated charger or hardwire.... just use the included mobile charger.

Aside from the reliability issues of the FMC

 

[chrisGT]

For me the most important feature for a charger is to have adjustable Amperage from a mobile app (not having to remove the charger cover like the Grizzle).
Why? When I want to recondition the 12v battery, I set my charger to 20A, which increases the charge time, and thus the time the 12v gets conditioned. But if I want to get a quick charge because I need extra range I can increase it to 40A.
And yes I have used Carscanner to monitor the 12v battery during charging and it gets charged to a much higher SoC when I charge at 20A.

Switching to low amps can also be useful if you want to run simultaneously other big electrical loads like an oven, dryer, A/c and your house is current-limited like the old 100A installations.

 

[dtbaker61]

For me the most important feature for a charger is to have adjustable Amperage from a mobile app (not having to remove the charger cover like the Grizzle).
Why? When I want to recondition the 12v battery, I set my charger to 20A, which increases the charge time, and thus the time the 12v gets conditioned. But if I want to get a quick charge because I need extra range I can increase it to 40A.
And yes I have used Carscanner to monitor the 12v battery during charging and it gets charged to a much higher SoC when I charge at 20A.

Switching to low amps can also be useful if you want to run simultaneously other big electrical loads like an oven, dryer, A/c and your house is current-limited like the old 100A installations.

if you want to give your 12v battery a long charge, there is no need to charge the HV slower.... Although I suppose you *could* just use the mobile charger with 120v tail, and let it charge for days...

- turn on your MME
- disable the auto-off setting
- leave it 'on' as long as you want... it will be holding the LV system at 14.5v which will get your LVB up to 100%

 

[chrisGT]

if you want to give your 12v battery a long charge, there is no need to charge the HV slower.... Although I suppose you *could* just use the mobile charger with 120v tail, and let it charge for days...

- turn on your MME
- disable the auto-off setting
- leave it 'on' as long as you want... it will be holding the LV system at 14.5v which will get your LVB up to 100%

Have you tested either of the scenarios you described? I have..
Plugging at 120v does not seem to recondition the 12v battery the same way as 240v.
Also if you leave the car on but you are not inside (open driver door, get out and close the door) the voltage on 12v terminal drops to 13.x instead of 14.x and then it takes forever to increase its SoC.

 

[dtbaker61]

Have you tested either of the scenarios you described? I have..
Plugging at 120v does not seem to recondition the 12v battery the same way as 240v.
Also if you leave the car on but you are not inside (open driver door, get out and close the door) the voltage on 12v terminal drops to 13.x instead of 14.x and then it takes forever to increase its SoC.

I'm just offering options on how you CAN give the LVB an extended charge. I don't actually think it is even required since 'normal driving' should provide adequate charging of the LVB. The easiest way like I said is just to leave your MME 'on' overnight, whether you are charging or not.

 

[Blue highway]

exactly....
so the included mobile charger plugged into a standard 14-50 outlet is 'enough'

there is literally no need to buy a dedicated charger or hardwire.... just use the included mobile charger.

I agree this will work... and does for many. My reasons for not using the Ford cable daily is so that the Ford charger stays in the car if for whatever reason it's needed away from home I have it... and the Grizzle is a physically much more robust device for daily use.

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