How to reduce L1 charging rate to 600W?

Hi All - because of overload on the 120V circuit (15A), I need to reduce my charging rate from 1.3 kW to 0.6 kW (or thereabouts). Is there a way to instruct the Leaf to draw less current or have the Nissan standard L1 brick tell the charger not to draw more than 5 amps? Thanks in advance to all replies. :?:

I believe 6a is the minimum the car will draw, a EVSEupgraded EVSE will go down to 6a, I don't believe there is a way to limit the charging on the vehicle, it would need to be done at the EVSE.

edit: when I say "draw" I mean under normal charging, the vehicle will draw less during final top up but I believe your EVSE needs to be set to at least 6a to start the charging. As others said later other EVSE's can go down to 6a also(my JuiceBox does) but EVSEupgrade is going to be your most economical option.

6a is J1772 minimum spec so 720 watts is minimum. You will need to increase the available power.

EVSEUpgrade can be adjusted down to the 6a minimum. And it works, I had one with my LEAF.

Otherwise you are looking at a custom build through Open EVSE or similar.

also keep in mind that there is a inefficiency charging at lower power. Charging at 120v 6a (720W aka .72KW) will charge the car about 30% to 40% of charging at 120v 12a which by the way will pull about 1.1KW. The catch is about 200W or so is used by systems that turn on during charging and don't count towards putting energy in the battery so the lower your charge power the higher overhead is as a percentage leaving less to charge the battery.

It'll be so slow as to be almost useless and will keep your car tied up and heating all that time. It's doable just not worth the trouble.

and it'll charge even less efficiently than the quoted numbers below, costing more money from the grid to do the same charging (more waste heat in the cars systems)

Full charge rate for the 3.6KW charger was around 88.x% (maybe 88.3 or so). Less efficient at full amps
Max efficiency for the 3.6KW charger was around 89.x% (maybe 89.5 or so). But around 12a not 16a.

Max efficiency for the 6.6KW charger was around 90.x% (maybe 90.5 or so). More amps is better on this one.

Max efficiency for the 120V with 3.6KW charger was around 86.x% (closer to 86.25 or so)
Max efficiency for the 120V with 6.6KW charger was around 78% (closer to 77.9% or so)

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It'll be so slow as to be almost useless and will keep your car tied up and heating all that time.

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I agree that 600 watts would be very slow, but heating at even 12 amps on L-1 isn't an issue in normal or even normally hot weather. It adds barely enough heat to stop the battery warmer from coming on at 5F.

I wouldn't say useless, but it would take well over a day to fully charge at that rate.

LeftieBiker said:

It'll be so slow as to be almost useless and will keep your car tied up and heating all that time.

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I agree that 600 watts would be very slow, but heating at even 12 amps on L-1 isn't an issue in normal or even normally hot weather. It adds barely enough heat to stop the battery warmer from coming on at 5F.

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I get 5F or better in the summer if I charge at 120v * 12a at work. I can't say exactly how much it is because if it is cool enough the pack cools and if warm enough the pavement is baking the pack. But 5F is a safe estimate because around the midline (days in the 70s F) that is what I see.

If he is going to charge at 120v * 6a he'll get similar heating (though obviously less) and if the pack is over 80F as read by leafspy at any point I'd avoid it.

He is in Southern California meaning he'll see near Arizona levels of degradation. If he was in Washington state or Oregon I might say "eh, who cares". But a socal leaf is gonna bake and bake.

wmcbrine said:

I wouldn't say useless, but it would take well over a day to fully charge at that rate.

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If he's getting 4 miles to the kWh and he gets maybe 1 KW charge in 3 hours at that rate he gets just over 1 mile per hour charging.

A not to full 16 kWh charging session would last 48 hours.

Heaven forbid he want to charge from VLBW to full it could take more than 2 days.

If he only charges 16 hours a day at that rate he'll have a usable range of about 22 miles a day.

Not useless in the literal sense, on that you are correct, but very limiting.

Of course if he is charging at that rate at night for say 8 hours and then charges on a L2 or Chademo when at work or on a shopping trip it will at least extent his range 10 miles or so a night.

The better option is to set up a dedicated circuit for your charging at 120v. Even if you have to purchase a heavy duty extension cord to reach the leaf, it is still better than trying to limit the charging current. JMHO

Do not use 120V circuit. You have to have dedicated circuit for best results. Charging at 600W (half of that will
be used on parasitic load) will take 3 days to charge.
Upgrade your OEM EVSE brick to accept 240V and then keep it at 10A if you want.

You have a car that costs thousands and thousands. Doing some electrical work for LESS than 1 thousand should be reasonable.