220v charging - anyway to limit amp draw

skomarla

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Hi all,

Is there any way to limit the amp draw when plugged into a 220v? My brother in law's work has 220v outlets but limited to 20A. So when plugged in, the breaker keeps tripping. Obviously upgrading the breaker is not an option.. out of luck?

Thank you
 
To clarify, he has a pure awd but I don’t think there is meaningful difference on this front.
Anyway I figure this is a shot in the dark to see if anyone has suggestions.

Thank you
 
Your EVSE is the issue and should be the device limiting power. It shouldn't be possible to plug one in that will draw >20A into a 20A outlet. Pretty big electrical code violation. For a business, that tends to be a very big deal in terms of insurance/etc.
 
Yea that makes sense but I’m more thinking along the lines of how the LCHC has dip switches to set the draw.. wondering if there are portable solutions out there without violating code.

Still think it’s a shot in the dark but just checking with the experts here.
 
Your EVSE is the issue and should be the device limiting power. It shouldn't be possible to plug one in that will draw >20A into a 20A outlet. Pretty big electrical code violation. For a business, that tends to be a very big deal in terms of insurance/etc.
There isn't a charger, it's a 220V outlet. I use the Lucid portable charging cable with a plug adapter. So the current limiter should be the vehicle which is likely defaulting to 40A or so. The Teslas, Toyotas, etc. all seem ok with it somehow.
 
There isn't a charger, it's a 220V outlet. I use the Lucid portable charging cable with a plug adapter. So the current limiter should be the vehicle which is likely defaulting to 40A or so. The Teslas, Toyotas, etc. all seem ok with it somehow.
One of few functions of the "AC charger" is to tell the car the maximum acceptable current. Lucid mobile charging cable does that, and should tell different limit depending of the adaptor used. Looks like using NEMA 14-30 plug adapter should set the limit to 24A: https://lucidmotors.com/media/document/lucid-mobile-charging-cable-na-user-manual.pdf
 
There isn't a charger, it's a 220V outlet. I use the Lucid portable charging cable with a plug adapter. So the current limiter should be the vehicle which is likely defaulting to 40A or so. The Teslas, Toyotas, etc. all seem ok with it somehow.
It can't, because you're using a plug adapter. You can't use a plug adapter like this. The EVSE has to be aware of the current limit or be able to set the current limit.

Do not use plug adapters/extension cords of any sort with charging equipment. I'm pretty sure they say that very clearly on the label even.

One of few functions of the "AC charger" is to tell the car the maximum acceptable current. Lucid mobile charging cable does that, and should tell different limit depending of the adaptor used. Looks like using NEMA 14-30 plug adapter should set the limit to 24A: https://lucidmotors.com/media/document/lucid-mobile-charging-cable-na-user-manual.pdf

Still too much for a 20A circuit by a lot. You can't go over 16A constant draw on a 20A.

From the manual, their EVSE doesn't provide what you need. You need a 3.6kW option for a 6-20.
 
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There isn't a charger, it's a 220V outlet. I use the Lucid portable charging cable with a plug adapter. So the current limiter should be the vehicle which is likely defaulting to 40A or so. The Teslas, Toyotas, etc. all seem ok with it somehow.
welcome 🤣
 
I think this feature should have been available on the car side. It's a big miss from Lucid. It's available in most other vehicles. I think Tesla can even do this at 1A increment. For eg: If I have a 48A Level-2 charger, but I want the car to limit the amp to 40A just to be on safe side, I would expect the car to have control available.
 
I think this feature should have been available on the car side. It's a big miss from Lucid. It's available in most other vehicles. I think Tesla can even do this at 1A increment. For eg: If I have a 48A Level-2 charger, but I want the car to limit the amp to 40A just to be on safe side, I would expect the car to have control available.
And it should be relatively easy to implement it as the car has all required hardware already: it's the integrated Wunderbox who controls the current, the EVSE only tells it the maximum acceptable current using pretty dumb protocol over the control wire.
 
There is no reason to implement it in the car. It's not allowed by electrical code to connect the plug to a lower rated receptacle. It's unsafe to do this at any time.

The correct solution is to have the correct plug end on the EVSE, which will make the EVSE report the proper safe current.

There are plenty of 6-20P EVSE available, even if the Lucid one does not support it.


The only practical reason to have this on a vehicle (and you still still do it at the EVSE) is if you have a situation where you have something like solar and you want to use a properly rated circuit, but stay underneath your solar capacity so you don't draw from grid or something. The circuit still has to be rated for the full possible current of the EVSE for it to be "legal" though.
 
I'll try to clarify ... the correct outlet needs to be installed onto the circuit first that must meet code requirements.

The Lucid mobile charger will draw as much current as it can which is determined by the installed adapter ... only the correct adapter can be inserted into the outlet.
 
I'll try to clarify ... the correct outlet needs to be installed onto the circuit first that must meet code requirements.

The Lucid mobile charger will draw as much current as it can which is determined by the installed adapter ... only the correct adapter can be inserted into the outlet.
Right, was trying to avoid 'adapter' since he's using presumably a not-so-legal 14-50R to 6-20P adapter right now. Which is a thing that shouldn't exist.

The EVSE plug end must natively match the outlet/receptacle which must be wired for the proper rated amperage with a properly rated breaker. It all has to be correct/the same. You can't just slap a converter in there.
 
My understanding is that the building he works has 14-50 outlets on 20A breaker available for EV charging use while parked. This setup is the source of the problem.

He is using the lucid supplied portable charger and the plug attachment it came with (14-50).. Another adapter is NOT in the loop..

1728075463962.webp
 
Hi all,

Is there any way to limit the amp draw when plugged into a 220v? My brother in law's work has 220v outlets but limited to 20A. So when plugged in, the breaker keeps tripping. Obviously upgrading the breaker is not an option.. out of luck?

Thank you
The Lucid charger only has 2 240 options at this time. 14-50 plug that will draw 40 amps and the 14-30 which will draw 24A. Lucid does not currently have software capability to set a lower limit. It is possible, but unknown if they will ever implement.
Below is a link for a third party charger that allows you to manually set a lower AMP draw.

 
The Lucid charger only has 2 240 options at this time. 14-50 plug that will draw 40 amps and the 14-30 which will draw 24A. Lucid does not currently have software capability to set a lower limit. It is possible, but unknown if they will ever implement.
Below is a link for a third party charger that allows you to manually set a lower AMP draw.

ding ding ding! Thanks. I’ll relay.
 
My understanding is that the building he works has 14-50 outlets on 20A breaker available for EV charging use while parked. This setup is the source of the problem.
And this setup is against standards as 14-50 is supposed to provide up to 50A
 
My understanding is that the building he works has 14-50 outlets on 20A breaker available for EV charging use while parked. This setup is the source of the problem.

He is using the lucid supplied portable charger and the plug attachment it came with (14-50).. Another adapter is NOT in the loop..

View attachment 23699
Well if he ever decides he hates the place and quits, he can also point the code inspectors over there.

Unfortunately they've given you a headache, because the 6-20P chargers can actually be pretty cheap since they're only 3.6kW. The one for my Volvo was only like $170. The mobiles that have a 14-50P are generally 40A capable and tend to cost more in the $500 realm.
 
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