Rivian charger vs. other charging devices

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dmnyc

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Ok. What about a nema 1450 outlet using say 40 Amps?

or can the Rivian box support 80 amps or 90 or a 100 amp breaker?
That’s a question for Rivian support, I’m new to this.
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timesinks

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so do I understand that the Rivian hard wired wall mounted wall charger only provides 25 miles per hour? Thats it?
Yes. Because EVSEs and onboard chargers are not rated in miles, they are rated in kilowatts. The onboard charger maxes out at 11.5kW (48A at 240VAC). You could plug it in to an 80A Level 2 EVSE, but the truck is configured to accept a maximum of 48A, so you won't notice any difference in Level 2 charge times.

Since these vehicles consume more energy (kWh) to propel themselves than the smaller and more aerodynamic EVs to date (Rivian is 480Wh/mi vs a Model 3 at 250Wh/mi), one hour spent charging it at the same power level will put fewer effective miles into the battery.

11.5 kilowatts times 1 hour is 11,500 watt-hours. The same amount of energy represents just shy of 24 miles in an R1T or a whopping 46 miles in a Model 3.
 

CommodoreAmiga

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so do I understand that the Rivian hard wired wall mounted wall charger only provides 25 miles per hour? Thats it?
The Rivian hardwired EVSE can provide up to 48A @ 240V. That is 11,520W. According to the IEEE, a level 2 EVSE averages 89.4% efficiency, so of that 11,520W consumed, 10,298W actually makes it into the battery as stored energy. Rivian EPA estimate is 314 miles for the Large battery, which is 135kWh. That is a per-mile energy use of 430W. 10,298W would therefore give you ~23.95 miles of range for each hour you’re charging.

The formula is basically:

RangeGainedPerHour = ChargerCurrent * InputVoltage * ChargerEfficiency / (BatteryCapacity / EPAMiles)

You can see, based on that data, how the efficiency (W/mile) of the EV Is a critical factor when determining how many miles you gain per hour on a given EVSE.

Yeah that’s standard for 240V 30 amp household current.
The hardwired Rivian EVSE “wall” is capable of 48A. It’s ~25 miles range gained at 48A. At only 30A that would drop to ~15 miles per hour.

Ok. What about a nema 1450 outlet using say 40 Amps?

or can the Rivian box support 80 amps or 90 or a 100 amp breaker?
At 40A you could expect approximately 20 miles per hour of range gained.

You can connect the Rivian EVSE to an 80+A circuit, but it will still only pull a max of 48A.
 
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The Rivian hardwired EVSE can provide up to 48A @ 240V. That is 11,520W. According to the IEEE, a level 2 EVSE averages 89.4% efficiency, so of that 11,520W consumed, 10,298W actually makes it into the battery as stored energy. Rivian EPA estimate is 314 miles for the Large battery, which is 135kWh. That is a per-mile energy use of 430W. 10,298W would therefore give you ~23.95 miles of range for each hour you’re charging.

The formula is basically:

RangeGainedPerHour = ChargerCurrent * InputVoltage * ChargerEfficiency / (BatteryCapacity / EPAMiles)

You can see, based on that data, how the efficiency (W/mile) of the EV Is a critical factor when determining how many miles you gain per hour on a given EVSE.


The hardwired Rivian EVSE “wall” is capable of 48A. It’s ~25 miles range gained at 48A. At only 30A that would drop to ~15 miles per hour.



At 40A you could expect approximately 20 miles per hour of range gained.

You can connect the Rivian EVSE to an 80+A circuit, but it will still only pull a max of 48A.
Thanks for the explanation! Electrical current capacity is not something they teach in the standard school curriculum.
 

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The Rivian (and other "smart" EVSEs) have the potential to communicate with your utility provider (V1G) and lets them delay/slow your charge session for a monthly/yearly discount.
The smart EVSEs also allow you to track the energy you use for charging, see charging curves, etc. Neat, but not required.
Yes, it has the potential to do these things as it can connect to the internet but there is no hint in the installation manual that there is anything smart about this EVSE nor is there any suggestion or promise that the App or the server it connects to will be able to even share between two of their own vehicles. So the question is has Rivian mentioned any of this somewhere else?
 

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so do I understand that the Rivian hard wired wall mounted wall charger only provides 25 miles per hour? Thats it?
The amount of "miles" that can be loaded per hour cannot be determined because one does not know, a-prori, how much energy he will use in going one mile. As he learns his vehicle he will have a pretty good idea as to what that number will be for various driving conditions. In the interim we have the EPA rating numbers which suggest that it tales 480 watts from the wall to do a mile.

The RIvian hard wired wall charger requires a 60 A circuit (though it can be installed on smaller circuit if that's all that is available in which case the number has to be scaled down by the ratio of the breaker you use to 60A). The 60 A circuit must be derated to 48A and that means, at 240 V, power of 240*48 watt hours per hour. As the vehicle requires 480 watt hr per mile the miles per hour are 240*48/480 = 24.

Yeah that’s standard for 240V 30 amp household current.
This comment is irrelevant as the EVSE is not on a 30A 240V circuit but rather a 60A 240 V circuit derated to 48A. The closest tp 30A for such EVSE is 32A derived from a 40 A circuit derated to 32A. Such a circuit (and the mobile connector is assumed to be plugged into such a circuit even though it may, in fact, be plugged into a 50A circuit) will thus charge the car at 240*32/480 = 16 miles (2/3 of 24).

Note that battery size, charger efficiency and EPA range rating do not come into this. The EPA electric consumption is as provided at the inpit to a charger - supposed to help you figure out how much you will have to pay the electric company to drive the vehicle,
 
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Here is a site that estimates your charge time based on your amp/volts available. I have no idea if it's accurate. Someone with a EV could maybe speak to that. Rivian is loaded on the site. At 240 volt 46 amp they show you reach the on-board charger limit.

https://evcompare.io/charging-calculator/


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ajdelange

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Here is a site that estimates your charge time based on your amp/volts available. I have no idea if it's accurate. Someone with a EV could maybe speak to that. Rivian is loaded on the site. At 240 volt 46 amp they show you reach the on-board charger limit.
Clearly it is not right as the limit for Rivians is 48A.

Most people should be able to handle

mph = 0.1*volts*amps/EPA

in which EPA = the EPA kwh/100 mile number.

mph/EPA_range is the fraction of the battery capacity added in 1 hr, 100 times that is the percent of battery added per hour and EPA_range/mph is the hours required for a full charge.
 
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Is there a specific advantage to buying Rivian’s charging box as opposed to one from Grizzl-e, for example? I know the Rivian device connects to Bluetooth through the app, but I’m not sure is this is a must-have feature. I’d like to get one that can be easily moved from its wall-mount, and the Rivian box looks like it needs to be partially disassembled in order to be attached and detached.
There might be advantages to the Rivian chargers that they haven't told us about yet. Rivian's unit might be programmable to only allow charging your rivian vehicle and not any random car that plugs in. This is not normally part of the J1772 standard but the extensions on that standard theoretically support it. If I were installing the charger in a "public" place and had to pay for the power, I'd definitely appreciate some sort of automatic access control on it.

I haven't had a chance to disassemble the Rivian APK yet to see if there are any neat secrets hidden in it, but I will some point soon.
 

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Yes, it has the potential to do these things as it can connect to the internet but there is no hint in the installation manual that there is anything smart about this EVSE nor is there any suggestion or promise that the App or the server it connects to will be able to even share between two of their own vehicles. So the question is has Rivian mentioned any of this somewhere else?
I guess there is some hope to be derived from the manual's statement that slow blue pulsing of the LED bar indicicates an OTA update is taking place.
 

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Yes. Because EVSEs and onboard chargers are not rated in miles, they are rated in kilowatts. The onboard charger maxes out at 11.5kW (48A at 240VAC). You could plug it in to an 80A Level 2 EVSE, but the truck is configured to accept a maximum of 48A, so you won't notice any difference in Level 2 charge times.

Since these vehicles consume more energy (kWh) to propel themselves than the smaller and more aerodynamic EVs to date (Rivian is 480Wh/mi vs a Model 3 at 250Wh/mi), one hour spent charging it at the same power level will put fewer effective miles into the battery.

11.5 kilowatts times 1 hour is 11,500 watt-hours. The same amount of energy represents just shy of 24 miles in an R1T or a whopping 46 miles in a Model 3.
Understanding that the onboard charger is the gatekeeper for rate of charge…is that due to hardware in the vehicle or software? Would it benefit having extra capacity for future updates/ improvements? Or is this a one and done deal?
 

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Understanding that the onboard charger is the gatekeeper for rate of charge…is that due to hardware in the vehicle or software?
Technically both, but the hardware has an upper limit and i seriously doubt the Rivian is capable of more than the specced 11.5 kW
 

ajdelange

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As is almost always the case in this context the answer is that it is software which determines the current the car requests (via a signal generated in hardware - not the charging hardware) but that the software is programmed to reflect the hardware's (this time it is the charging hardware) limitations . For example a Tesla owner can set the maximum Level 2 charging rate he wants on the main touchscreen but he cannot set it, in the current crop of cars, above 48 A (in my old X I could dial it up to 72). There is somewhere in the code a parameter table and the entry for maximum charge current is now set to 48. It is set to 48 because the charger hardware cab only handle 48. If, in the future, Tesla goes back to bigger chargers, they will change the software to reflect this.
 

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What about the other charges on the market? Would love to hear people's experience with things like the JuiceBox, WallBox, Chargepoint or Electrify America. I will not be getting the Rivian charger as it requires the hardwiring, sucks because I just had a 50 AMP NEMA 14-50 pulled to my garage but most of the third party chargers work with this outlet type.
 

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What about the other charges on the market? Would love to hear people's experience with things like the JuiceBox, WallBox, Chargepoint or Electrify America. I will not be getting the Rivian charger as it requires the hardwiring, sucks because I just had a 50 AMP NEMA 14-50 pulled to my garage but most of the third party chargers work with this outlet type.
My experience so far is my ChargePoint Home Flex looks great on my floor :) I can't get an electrician to respond to my inquires and come and install. Construction is super backed up here. Amazingly, the L1 charger the car came with is working just fine
 
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