High Inverter/Outlet Battery Drain

[messinator]

I’m planning a 3 week road trip through the Canadian Rockies in a month and experimented with keeping my inverter / outlets running without any load to test the battery loss.

Sitting parked and locked with the outlets on, the truck lost 16% (72->56%) in 48 hours. Ouch!! Looks like I’ll be sticking to coolers - too much draw to run a fridge and I don’t want to purchase a $300 battery so I can then purchase a $600 fridge.

Have other folks seen similar battery drain?

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[Marchin_MTB]

Thanks for the report, yikes. We use our outlets sparingly when camping. 30-60 minutes a day to cook and power a few other items so never had this kind of hit.

 

[Aardvark]

When you say "keeping the inverter on," are you referring to the internal inverter that powers the 120 V socket? Or, did you plug in an external inverter in the 12V DC socket?
If the former, that 16% loss seems huge. Thanks for the heads up. We've also got a camping trip coming up.

 

[Marchin_MTB]

I think this is why they put a timer on the inverter controls. But if these numbers are correct, the inverter eats just over 400W in standby, that does seem rather high. @messinator was the cabin nice and toasty after this test?

 

[messinator]

Right, by inverter I’m referring to the outlets sorry. The cabin was already absurdly hot due to it being 90deg in Seattle this week so couldn’t tell ?

 

[Electrified Outdoors]

Yes it keeps the whole truck awake too plus it keeps the inverter running. 20% seems like a lot but Tesla with sentry mode enabled can lose 7% a day normally when it's parked.

 

[dstraede]

Be careful with the cigarette 12-volt port. If you drain the small 12-volt battery, you will brick the car, and it will be locked, requiring many hours to get back in. This will require special ordering of a new battery.

 

[sagebrush2]

Yes this amount of drain seems only slightly higher than what I have seen. My numbers are similar, but with actual usage of a cooler and stove and going in and out of vehicle. I had concluded that actual usage drain was a fraction of drain of just having the outlets on. So I have purchased a battery to keep the electric cooler running and turn on the outlets only when needed.

 

[Riviot]

the truck lost 16% (72->56%) in 48 hours

So 8% / 24hrs, that seems about right. When we camp and use the electric blanket, have a fridge, and cook dinner/breakfast on an induction top, total loss is about 8% in 14 hours.

Be careful with the cigarette 12-volt port. If you drain the small 12-volt battery, you will brick the car, and it will be locked, requiring many hours to get back in. This will require special ordering of a new battery.

So long as you keep the outlets on, both DC-AC and DC-DC converters remain on. I've had my fridge plugged in overnight, multiple times, and 50k miles later still have the original battery.

AFA inverter generating cabin heat, I crack the windows when it's warm out but keep them up when it's chilly, it'll help keep the battery warm!

 

[docwhiz]

I’m planning a 3 week road trip through the Canadian Rockies in a month and experimented with keeping my inverter / outlets running without any load to test the battery loss.

Sitting parked and locked with the outlets on, the truck lost 16% (72->56%) in 48 hours. Ouch!! Looks like I’ll be sticking to coolers - too much draw to run a fridge and I don’t want to purchase a $300 battery so I can then purchase a $600 fridge.

Have other folks seen similar battery drain?

I use a $200 12v refrigerator connected to a $200 "solar battery" which is charged from the lighter socket. Minimal power draw. Works great on trips.

 

[Joe schmoe]

Be careful with the cigarette 12-volt port. If you drain the small 12-volt battery, you will brick the car, and it will be locked, requiring many hours to get back in. This will require special ordering of a new battery.

Im a bit skeptical about this--and I had a conversation with customer support about it last week. They said it wasn't clearly documented, but should be fine.

I'm planning a 3-4 day camping trip net week, and have had a BougeRV 23qt fridge running in my spare tire well (R1S) since Thursday. except for a few short drives, I've kept the truck in camping mode with the HVAC and displays off, but energy management set to "keep on."

As others have reported, this results in a pretty large overhead/vampire drain of around 10%/day.

The refrigerator pulls 45w in Ma mode, and 35 in Eco mode while running, negligible while idle. I can't tell that the refrigerator makes much difference at all in the HV battery drain.

As far as the 12v battery draining--this should be a specific design point. the HV battery tops off the 12v when voltage sags. I'd assume that the 12v exterior lights by themselves are at least 80-100w and we don't worry about running them for hours at a time. The headlights would probably drain the tiny 12v battery in a couple of hours at most all by themselves--I'd guess that the full 12v load wouldn't last 30 minutes

I'd question the dollar figures a bit as well--a $300 dollar battery won't run a refrigerator for long--probably need at least $5-600. And while I know you can spend $600 (or $1000) on a 12v refrigerator, it doesn't seem necessary--I paid $161 plus tax last week for the BougeRBV 23 qt which is well reviewed and seems to work well. It also fits in the spare tire well which is a plus.

 

[docwhiz]

Im a bit skeptical about this--and I had a conversation with customer support about it last week. They said it wasn't clearly documented, but should be fine.

I'm planning a 3-4 day camping trip net week, and have had a BougeRV 23qt fridge running in my spare tire well (R1S) since Thursday. except for a few short drives, I've kept the truck in camping mode with the HVAC and displays off, but energy management set to "keep on."

As others have reported, this results in a pretty large overhead/vampire drain of around 10%/day.

The refrigerator pulls 45w in Ma mode, and 35 in Eco mode while running, negligible while idle. I can't tell that the refrigerator makes much difference at all in the HV battery drain.

As far as the 12v battery draining--this should be a specific design point. the HV battery tops off the 12v when voltage sags. I'd assume that the 12v exterior lights by themselves are at least 80-100w and we don't worry about running them for hours at a time. The headlights would probably drain the tiny 12v battery in a couple of hours at most all by themselves--I'd guess that the full 12v load wouldn't last 30 minutes

I'd question the dollar figures a bit as well--a $300 dollar battery won't run a refrigerator for long--probably need at least $5-600. And while I know you can spend $600 (or $1000) on a 12v refrigerator, it doesn't seem necessary--I paid $161 plus tax last week for the BougeRBV 23 qt which is well reviewed and seems to work well. It also fits in the spare tire well which is a plus.

You don't need a big battery if it's going to be plugged into the cars 12v supply most of the time.
Refrigerators draw about 50W when they're operating. Duty cycle depends on ambient temperature but lighter adapter should have no problem keeping up. Even a small 300 Wh battery can easily run the refrigerator for a day depending on ambient.

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