EV Charging - how to adjust charging amperage?

[California]

Daughter just bought a Chevy Equinox. When she comes up to the ranch I want her to charge here. Last visit we used a 120v 20a outlet.

in my shop I have an old 'dryer' 3-blade 240v outlet and an adapter from that to standard welder outlet. Fed from a 30 amp dual breaker on a 100 amp sub-panel.

I just bought the adapter to plug the modern EV cord into the old 3-blade outlet.

My question is, how to adjust down the amperage that the Equinox pulls? I see the Ultium cord/controller that came with the car can pull 32 amps, but that seems dangerously high for continuous load on the ancient farmer-wired Federal Pacific (!) breakers and circuits here. We charged this afternoon at default settings. An 'infrared' thermometer didn't find any notably warm spots after several hours. 80 degrees on the charger brick and the outlet. 85 degrees at the 30 amp breakers feeding the outlet was the maximum found. Below 80 on this sub panel's input breakers and the house (source) 200 amp input and 100 amp shop (output) breakers. But I unplugged the charger overnight just to be cautious.

Anybody have an Equinox? All I can find online is marketing junk and discussion of Chevy's previous charger, not this 2025 version.

How do I l set the EV (or charger?) to pull 24 amps or less? Any advice?

 

[dougtrr2]

Don't confuse what the cord is rated for, with what is actually being drawn in use.

Doug in SW IA

 

[California]

Don't confuse what the cord is rated for, with what is actually being drawn in use.

Doug in SW IA

True. But the question is how do I define what is being drawn?

 

[ponytug]

@California I think that is a great idea to check the temperature of the circuit! What amperage welder outlet are we talking about? 30A? 50A? (60A?) Do you know the wire gauge and metal?

I think that the Equinox has options in the charging page, but my dim recollection is that it doesn't have the option to down rate the 240V charging. But, the Equinox supposedly maxes its AC charging at 11.5kW (49A, which is at the two/three hour max for a 50A circuit)

There are snazzy wall adapters ($500+/-) that will tell the vehicle that the maximum charge rate is X.

All the best,

Peter

 

[Gale Hawkins]

On our 2016 leaf it can draw up to 26 but I don't haven't gotten away to modify that which is not a problem in my case because I have a 40 amp breaker to the outlet so I'm good up to 32.

Now the Tesla lets me micromanage the current rate.

 

[5030]

...and I just passed up a heck of a deal on a very low mileage Tesla coupe. Wife said no so I passed.

 

[California]

@California I think that is a great idea to check the temperature of the circuit! What amperage welder outlet are we talking about? 30A? 50A? (60A?) Do you know the wire gauge and metal?

When i bought my first welder, and ancient 230A - AC stick welder similar to a Tombstone, I cobbled up an outlet for it using junk on hand. Federal Pacific twin 30A breaker, 12 inches of 10 ga wire down to an ancient dryer outlet, then a used dryer pigtail to a 6-50 outlet. (Photo) This 30 amp circuit has served well for various welders claimed to need 50 amps, but I've never run the 230A welder at full output. So this 30A twin breaker has never tripped.

For welding this has worked fine. An EV draws current continually, a much more severe load than an intermittent welder. So I need to pull less current from this circuit. Maybe 24 A in daytime where I can keep an eye on it, and less overnight.

I think that the Equinox has options in the charging page, but my dim recollection is that it doesn't have the option to down rate the 240V charging. But, the Equinox maxes its AC charging at 11.5kW (49A, which is at the two/three hour max for a 50A circuit)

There are snazzy wall adapters ($500+/-) that will tell the vehicle that the maximum charge rate is X.

The adapter that came with the car is a simple brick. (New version for 2025). I wonder if it responds to an app. Or if the car can be set to draw less.

Daughter, the car owner, has no instructions on how to do this.

 

[ponytug]

This would suggest that the 30A circuit requires the GM 30A dongle (shortie cord) for the brick to turn down the charge current;

https://www.equinoxevforum.com/threads/can-we-lower-l2-240v-charge-rate-down-to-24-amps.2039/

E.g. this shorty cord for her brick;


And of course a new NEMA 14-30 outlet...

All the best,

Peter

 

[scootr]

If the car won't let you limit amperage draw (24a might suit your circuit well for fast charging) then you can get a charger that will on Amazon, big selection there.
I'm using a Seguma brand 16 amps at 220v for the Tesla. That is plenty of input for overnight charging.
5030 your wife doesn't know the fun she is missing

 

[California]

Ponytug, I found that dongle diagram and it's the prior model of charger. The 2025 Equinox OEM dongle goes into an approximately square socket on the charger brick.

Scooter, at $350 to $500 included in her new car price for this charger brick, I'll try to make it work. I've read it pulls 32 amps natively, which I think is too much for this old farm wiring.

The updated Equinox charger brick we have, has a 14-50 dongle so I bought the adapter to get from that to my 10-50 'dryer' outlet. This works great but I still want to reduce the amperage going through it.

 

[scootr]

I have that same old 10-50P in my garage, old 50a welder circuit I ran in 25 yrs ago.
I'm resisting getting the higher 32a charger after reading a bunch of charging discussions which basically showed charging at a lower amperage stressed the battery less and slowed battery degradation vs supercharging or high home charging.... but that is a discussion that can go on and on and on.

 

[ponytug]

Ponytug, I found that dongle diagram and it's the prior model of charger. The 2025 Equinox OEM dongle goes into an approximately square socket on the charger brick.

Scooter, at $350 to $500 included in her new car price for this charger brick, I'll try to make it work. I've read it pulls 32 amps natively, which I think is too much for this old farm wiring.

The updated Equinox charger brick we have, has a 14-50 dongle so I bought the adapter to get from that to my 10-50 'dryer' outlet. This works great but I still want to reduce the amperage going through it.

Sorry I pulled the wrong part, but you want a 14-30 dongle for reduced current. The ones above look like they just adapts
the plug to your socket, but I do not believe it tells the brick to reduce the charge rate. True?

All the best, Peter

 

[California]

I agree, I don't think the choice of dongles determines amperage.

I can't find the specific information to reduce charge current, but as Scooter said, that would be better for battery longevity.

Also in our case, pulling less current will be safer for the non-code never inspected wiring here - my primary objective. The Federal Pacific panels and breakers are a known fire hazard, long off the market.

At any rate daughter's Equinox is now charged to 100% for her return home.

 

[Quaffer]

The Federal Pacific panels and breakers are a known fire hazard, long off the market.

Why don't you just replace the panel? Seems like a prudent thing to do even without the EV issue. These panels remind me of Zinsco ...

 

[California]

Why don't you just replace the panel? Seems like a prudent thing to do even without the EV issue. These panels remind me of Zinsco ...

Everything here is poor condition, not just the panels. Its all knob & tube wiring in the walls, touch it and the hardened tar insulation falls off. This small farmhouse is so primitive that the bathroom was the first add-on. Dad's advice was just bulldoze it when he was gone, that's the advice I'm telling my kids now.

The used Federal Pacific panels that were installed in the 1960's (without inspection) upgraded service to 200 amps 240v, I think this was for the 'modern' submersible pump in the well dug at that time.

Here's an example in the basement, showing first-generation (1920's?) wiring, extended to a lamp socket using cotton covered lamp cord. Starting any project here, encounters stuff like this. I think the 1960's cabling out to the barn is adequate gauge for the EV charger there, but the quality of that project's workmanship is suspicious. So I want to reduce the EV charge amperage to where it seems safe to leave it on overnight.

Added: I should note this isn't our primary home. We have a decent house in town. This was grandparents, then Dad's, now my, retirement hobby farm (apple orchard). So upgrading anything isn't a major priority. Just patching stuff for continued usability is our preference. As I noted, this really should have been bulldozed a generation ago.

 

[scootr]

I think buying a 16 amp amazon charger is the prudent thing to do given the age and condition of the house wiring. Running anything to max capacity has risks. Risks that are avoidable. 220v 16a is all I use. Works great, reduces battery stress and system stress. Costs less than $150 Amazon. What's not to like about this solution?

 

[Quaffer]

Everything here is poor condition, not just the panels.

Understood about old properties.

But, just sayin, it's pretty inexpensive and simple to change out a panel. Eliminates one possible point of fire or failure. Not so much to redo all the wiring.

You could also always consider getting a diesel generator and recharging it from that!

GL-11000 | GL Series | 60Hz | Products | Kubota Generator

 

[California]

Daughter has departed, 100% charged.

She visits every few weeks, so I think what we have is sufficient for her visits.

We'll use 12amps on a recently installed 20 amp 110v circuit for overnight charging, and the 240v charger (32 amps??) for daytime charging where we can keep an eye on it.

If/when I buy an EV, I'll get a pro electrician out here to review what we have.

I'm still searching for how to adjust the amps requested by the Equinox.

 

[ponytug]

Daughter has departed, 100% charged.

She visits every few weeks, so I think what we have is sufficient for her visits.

We'll use 12amps on a recently installed 20 amp 110v circuit for overnight charging, and the 240v charger (32 amps??) for daytime charging where we can keep an eye on it.

If/when I buy an EV, I'll get a pro electrician out here to review what we have.

I'm still searching for how to adjust the amps requested by the Equinox.

Using the better 20A circuit to charge at 12A sounds like a good plan in the interim. I'm glad your daughter got away OK.

There are some simple service items for the Federal Pacific bus bars, and a revised busbar if you want to go that route.

FWIW: The GM "cord dongle / shortie cord/adapter " contains electronic smarts that tell the car to limit the charging via an electronic handshake at power up what the outlet is capable of- it is part of the car charging standards. The yellow ones just adapt prongs, and do not have anything to tell the car that the outlet is less powerful.

All the best,

Peter

 

[LouNY]

This would suggest that the 30A circuit requires the GM 30A dongle (shortie cord) for the brick to turn down the charge current;

https://www.equinoxevforum.com/threads/can-we-lower-l2-240v-charge-rate-down-to-24-amps.2039/

E.g. this shorty cord for her brick;
View attachment 3221581

And of course a new NEMA 14-30 outlet...
View attachment 3221580

All the best,

Peter

That is for the "old" style Chevy brick. The new ones do not have that configuration. (Closed the page before I was done, fat fingers.)
You have found the correct information the "latest" Chevy charger does allow two currant choices when plugged into a 120 volt circuit using the my Chevy app. However it does not on the 240 volt operation, in that configuration it can and will pull a max of 32 amps.
My wife's is plugged into the welder receptacle in our attached garage, which fortunately is wired adequately to handle the constant current draw of 32 amps.