[Robb]

It’s a ChargePoint and it’s plugged into a 50A circuit and I’m seeing between 16-18 mph - I thought it supposed to be about 25. What everyone else getting? Amperage in the truck is set to 48 but running at 42.

thank you -

 

[Pickupman2022]

That sounds about right. You're only supposed to pull 80% of the circuit rating with a continuous load, so you should be at 40 amps max. When I've used a 40 amp (9.6 kW) I got about 18 mph. My current home setup is 48 amp (11.5 kW), which required the charger to be hardwired, not plugged in and a 60 amp circuit, Now my Rivian app usually fluctuates between 23 and 24 mph.

 

[Serh1830]

Correct. If you put in a 60amp breaker, it will pull 48amp and give you 25miles/hr at 11kW… it’s steady

EDITED: refer to user manual. I mistakenly was referring to Rivian Wall charger that states 60amp for maximum 48amp draw.

 

[Robb]

Thanks. Makes me wonder why my electrician didn’t put in a 60A breaker and hardwire the charger.

 

[Serh1830]

Easy to change. You can. Do it yourself. Be safe and kill the main. Worth changing to a 60amp.

 

[O. horridus]

Wait, OP said "It’s a ChargePoint and it’s plugged into a 50A circuit". There is nothing in that post that even hints that the charger is designed to output 48A to the vehicle on a 60A circuit, or that the charger is even capable of being hardwired.

Why would you suggest simply swapping the breaker? The existing wiring almost certainly does not support a higher current. You have no idea if the panel supports the higher load. And a NEMA 14-50 outlet does NOT support more than 40A continuous load in any case. So don't swap the breaker! It's against code and it's bad bad advice.

IF this is a ChargePoint model that can be hardwired, the electrician may have just not known that. IF the electrician used the right wire it MIGHT be possible to easily change your charger to be hardwired, but you should really have the electrician do that to make sure you're up to code.

 

[Serh1830]

I missed it was ChargePoint , and my inclination was the Rivian wall charger.

sorry the Extremely bad bad bad bad bad advice.

Wire gauge depends on length and breaker amp. I think we are talking generalities and certainly seems clear this advice comes with common sense about keeping code in mind.

 

[John B R1T]

Don't forget that required wire gauge also depends on wire type. Anything you're seeing regarding wire gauge should be automatically interpreted to be that gauge in COPPER. Aluminum is much different! Generally speaking, unless you're talking about the (huge) aerial drop to your house from the pole, you shouldn't even be thinking about aluminum.

 

[Serh1830]

PS- edited my original comment above to fix my error.

 

[Serh1830]

Thanks. Makes me wonder why my electrician didn’t put in a 60A breaker and hardwire the charger.

What’s the exact model of the charger? As you mentioned, Curious why it is plugged into a 50amp outlet as opposed to hard wired. Would be good to refer to the manufacturers IFU to see if it supports hard wire…

 

[Robb]

Thanks guys - all good and well intended. My ‘mistake’ was going with a CP charger instead of a Rivian which apparently is rated at 60A vs. the CP’s 50A. The 16-18 mph gives me what I need - and this discussion enlightened me sufficiently.

thanks again -

 

[Craignyc]

I have the charge point with a 60amp breaker, I get 11kw charging, however I spoke with chargepoint and they told me you can go to 60amp circuit to get the 14kw speed if its hardwired.

 

[mshobe]

I have Rivian's charger (on a 50A circuit which I should have wired for 60A, oh well) and I get ~17mph charge rates typically.

Interestingly, on a different,10 year old 14-50 NEMA outlet with a generic Chinese J1772 charger, it draws ~32A but the Tesla Model Y I have on that side of the garage frequently charges at ~30mph. Nearly double the speed. I'm no electrical engineer nor do I play one on TV, but does that advantage come down to software and hardware efficiencies Tesla's eked out over the years?

I'm really stunned at how much faster my M Y gets recharged.

 

[CommodoreAmiga]

Interestingly, on a different,10 year old 14-50 NEMA outlet with a generic Chinese J1772 charger, it draws ~32A but the Tesla Model Y I have on that side of the garage frequently charges at ~30mph. Nearly double the speed. I'm no electrical engineer nor do I play one on TV, but does that advantage come down to software and hardware efficiencies Tesla's eked out over the years?

The Tesla Model Y is a smaller, lighter, and more aerodynamic vehicle than the Rivian R1T. It is more efficient because physics. It's no different than how one gallon of gas will get you more range in a Toyota Prius than a Toyota Tacoma.

If you want to know the "math" behind it:

32A @ 240V is 7,680W.

A 2022 Tesla Model Y Long Range AWD has an EPA estimate of 28 kWh/100 miles. That's 280W per mile. That 7,680W you gained in 1 hour would therefore get you approximately 27.4 miles of range.

A 2022 Rivian R1T has an EPA estimate of 48 kWh/100 miles. That's 480W per mile. That 7,680W you gained in 1 hour would therefore get you approximately 16 miles of range.

 

[mshobe]

Wh/mi - right. Forgot that this isn't based on measuring a "flow" of charging energy but rather the ultimate efficiency of the machine.

A 2022 Rivian R1T has an EPA estimate of 48 kWh/100 miles. That's 480W per mile. That 7,680W you gained in 1 hour would therefore get you approximately 16 miles of range.

 

[Robb]

Yeah I wish my electrician - who has a good deal of experience installing EVSE’s and did a good job putting a new 240 circuit in our garage - had offered me the options of hardwired v. receptacle and 60A vs. 50A. I think he’s a ‘by the book’ guy and this is still a new area of tech for everyone. I guess I can always have it hardwired and a new circuit installed - right now it’s charging at 18-19 mph and 42A which is fine for my needs.

 

[CommodoreAmiga]

Yeah I wish my electrician - who has a good deal of experience installing EVSE’s and did a good job putting a new 240 circuit in our garage - had offered me the options of hardwired v. receptacle and 60A vs. 50A. I think he’s a ‘by the book’ guy and this is still a new area of tech for everyone. I guess I can always have it hardwired and a new circuit installed - right now it’s charging at 18-19 mph and 42A which is fine for my needs.

"By the book" is hardwired.

 

[tcaron3097]

That sounds about right. You're only supposed to pull 80% of the circuit rating with a continuous load, so you should be at 40 amps max. When I've used a 40 amp (9.6 kW) I got about 18 mph. My current home setup is 48 amp (11.5 kW), which required the charger to be hardwired, not plugged in and a 60 amp circuit, Now my Rivian app usually fluctuates between 23 and 24 mph.

I will be sharing a 30 amp circuit with the dryer. For my R1T what should I expect for mph?

 

[CommodoreAmiga]

I will be sharing a 30 amp circuit with the dryer. For my R1T what should I expect for mph?

12 miles of range gained per hour on a 30A circuit.

30A * 0.8 * 240V = 5,760W
5,760W / 480W/mi = 12 mi

 

[87Ducks]

On a related note, I am expecting delivery of my R1T next month and was wondering about home charging. I have a 240v 50A outlet in my garage so what is the advantage of the hardwired Rivian' charger over just plugging in with the cord in the frunk?