Testing the Rivian as a ‘backup’ power source

[MountainBikeDude]

Are you able to target the output of the outlets through the display, I know you can turn them on and off, but is there a sub menu within that functionality?

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[jjswan33]

Are you able to target the output of the outlets through the display, I know you can turn them on and off, but is there a sub menu within that functionality?

Not that I am aware of, I can’t even find any information about what is being drawn, a display showing power out would be useful.

 

[the long way downunder]

Almost certainly a ground loop. They ran into this at TFL trying to do the same thing with the Ford F150 (not the lightning, but still had power available). Check out this video about 2:30 in.

Right, I assume it's ground detection.

 

[the long way downunder]

Here's the info from the owner's manual. I'm sure if I take a watt meter and fan heater, it will deliver 1500W to a single outlet. I guess I could run it for an hour and then view the truck through a thermal camera and see what warms up … : )

 

[the long way downunder]

1500W confirmed

There's two outlets in the bed. I plugged a fan heater in and switched it from 700 to 1000 to 1500W (which surged to 1594W briefly.) No problem.

 

[lostpacket]

What are the chances this would be possible from the J1772/CCS port if you had an external inverter?

Also is there a way to bond the ground back to the truck's neutral? I am assuming the ground fault is being detected because the ground and neutral are bonded at the service entrance / panel?

(disclaimer: I am very much not an electrician, hence the possibly dumb questions)

 

[Zoidz]

Inrush current can be 3 to 7 times the running current on a refrigeration compressor. That will exceed the rating of the Rivian inverter. Here's the electrical specs for a Tecumseh AE4440Y refrigeration compressor, this is typical of a full size home refrigerator. Note that while the Rated Load Amps (RLA) is 5.82 Amps, the Locked Rotor Amps (LRA) is 32A. On a cold start, the inrush current can approach the LRA in the first 100 to 200 milliseconds. That's almost certainly the problem. You won't see this surge on any consumer current monitor. It happens too fast. 2nd image is an example of the current at startup of a refrigeration compressor.

You could try putting a soft start inline with the refrigerator. That may or may not help.

 

[the long way downunder]

What are the chances this would be possible from the J1772/CCS port if you had an external inverter?

Also is there a way to bond the ground back to the truck's neutral? I am assuming the ground fault is being detected because the ground and neutral are bonded at the service entrance / panel?

(disclaimer: I am very much not an electrician, hence the possibly dumb questions)

That's "vehicle to load" or V2L (also V2X "anything" and V2G "grid" and V2V "vehicle" … it's all just taking shape.) If Rivian has built the right hardware into the truck, V2L is easy and requires only a dongle from CCS to a suitable connector to power a house (you can read about this as done by Ford with the Lightning or the F-150 Hybrid.)
A tech at Rivian told me the charge port is undergoing a complete redesign. Hopefully Rivian will offer V2L and I imagine the charge point is the logical/easy place to tap into power for a Rivian-designed winch (though I'm told the winch project was recently cancelled .)

 

[jjswan33]

Inrush current can be 3 to 7 times the running current on a refrigeration compressor. That will exceed the rating of the Rivian inverter. Here's the electrical specs for a Tecumseh AE4440Y refrigeration compressor, this is typical of a full size home refrigerator. Note that while the Rated Load Amps (RLA) is 5.82 Amps, the Locked Rotor Amps (LRA) is 32A. On a cold start, the inrush current can approach the LRA in the first 100 to 200 milliseconds. That's almost certainly the problem. You won't see this surge on any consumer current monitor. It happens too fast. 2nd image is an example of the current at startup of a refrigeration compressor.

You could try putting a soft start inline with the refrigerator. That may or may not help.

As I said in my follow up above the circuit on the Rivian trips even when there is no load as soon as it is connected to the transfer switch. So I presume it is the ground loop as proposed by @PAFDenver

.

 

[pc500]

I tested 1750 watts and it worked fine. 2200 tripped it.

This was with a resistive load ie a hair dryer and space heater.

There's some buffer in there but it might not be as much as you need.

Although it's not the 2000 of your yeti I suppose it's probably tripping for other protective reasons unrelated to draw.

 

[ajdelange]

I did check and the truck will run my GZ battery charger but apparently it will only push my 600W charger at 355.7W.

That's about as fast as the 6kWh Yeti will accept charge so that can't be blamed on the truck. The big clue here is that the charger is isolated from ground (no earth pin on the plug) whereas the little transfer panel isn't. Thus the "system" is grounded in 2 places and a gfci trips.

You can still do what you want to do but you will have to get an isolation transformer ($$$).

 

[ajdelange]

It's probably an appropriate place to note that the Rivian is not intended for this sort of service. It's inverter is low power, single phase and apparently equipped with protective circuitry to prevent damage to itself if people try. Compare to the inverter in the CT or F150 which are much more robust biphase inverters intended to be able to operate hefty 240V loads at a construction site. The Rivian inverter is designed to run your Espresso machine at a glamping site.

 

[Zoidz]

As I said in my follow up above the circuit on the Rivian trips even when there is no load as soon as it is connected to the transfer switch. So I presume it is the ground loop as proposed by @PAFDenver

It wasn't clear to me that the load was disconnected when you plugged in. Specifically, does it trip with the transfer set to Line, and all load breakers off?

 

[jjswan33]

It wasn't clear to me that the load was disconnected when you plugged in. Specifically, does it trip with the transfer set to Line, and all load breakers off?

Yes exactly.

So I investigated further the Rivian trips out as soon as you try to plug it into the Transfer switch. I tried both with the switch set to Gen and Line. I guess it is some sort of safety built in against this use case.

 

[jjswan33]

I tested 1750 watts and it worked fine. 2200 tripped it.

This was with a resistive load ie a hair dryer and space heater.

There's some buffer in there but it might not be as much as you need.

Although it's not the 2000 of your yeti I suppose it's probably tripping for other protective reasons unrelated to draw.

Yeah the GZ is 2000W but with 3500W surge I guess the Rivian is 1500W with some surge capacity to handle the inrush of things like a refrigerator or a power tool.

I will do further testing at some point, for my camping setup I will need to know whether I need to add a more powerful inverter.

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