Field Experience With DC Refrigerator Power Consumption and Factory Solar

Lloyd

I have searched the forum looking for an answer regarding actual experience with DC power consumption and factory solar and haven't found what I am looking for. We will be boondocking for 3 days later in the month in a 2020 T@B 400 with factory installed solar. Specifically, given adequate sunshine, how many days could one reasonably expect to have an adequate power supply to run our frig? I know the frig has quite an appetite (12-13amps) so we will be vigilant regarding power usage. I am hesitant to add a generator to our list of essential items to have with us. Your input would be greatly appreciated. Thanks.

Sharon_is_SAM

If your frig is the 2 way, it is efficient on DC.  You can run the frig on DC/solar with good conditions indefinitely.
The 3 way frig in the 320 is a DC power hog.  

If you have a 3 way frig, just run it on LPG.

Lloyd

Thanks for the input. I failed to include that we have the 2-way frig.

TNOutback

With good solar production, indefinitely.  Our first trip in our 2020 last year was a boondocking trip in the mountains, with mix of clouds and sun, and rooftop panel oriented to the north and partially shaded.  After 4 days, we left with 80% charge remaining.  If you wanted to account for lack of solar production, you could always carry a small generator with you.  The rooftop solar and the extremely efficient 12V refrigerator is a fantastic setup. 

ScottG

Lloyd said:

Thanks for the input. I failed to include that we have the 2-way frig.

The 12-13 amp consumption you indicated seems more in line with the three-way fridge running on DC (which is intended to be used only when connected to a running tow vehicle). Two-way fridges operate by a totally different mechanism, and while I don't have the exact specs, I believe their power consumption is considerably less.

Lloyd

Thanks for the input, I appreciate it. Yes, it seems the 2-way and the 3-way are 'way' different–sorry, I couldn't resist–when it comes to power consumption.

AirBoss

Just a quick follow up here to round out the variables.

Fair to say if you're running a 3-way Norcold the best course of action to preserve 12V power supply is once cooled and stocked to the gills (day prior to departing on shore power), run on 12V (or not at all) while enroute. Once camped, shore power (it's already paid for) or propane if no shore power is available. If 12V becomes sole source, be vigilant, shut it down during the night, orient the rig to maximize solar, etc.  I suspect you could get by for a good number of days or perhaps weeks if necessary if the weather gods shined on you and you don't do nothin' dumb! 

Not much of a boondocker but I'd welcome thoughts from those who are...ya' just never know...

Cheers,  

pthomas745

What we need:  people to post screen shots of their Victron apps pointing out the power usage in real time while using the 2 way fridge.  

Deb55

@pthomas745 I'd help out with that, except our 400 is at the dealer for a bathroom fan replacement. If it's still needed when we get it back, I'll post the info. Any excuse to go play in the camper! 

Denny16

The TaB 400 has a two-way fridge, so running on 12VDC with the factory Solar, we are recharging the battery completely each day, and your only free camping restriction is going to be water, and waste.  You can run the electrical with average sun till the cows come home.
cheers

MarkAl

@Lloyd you didn't state your model / year but with my 2021 320S w/ factory solar (2 way frig) it's useless in the trees and facing North. That said I can easily get a 3 day dry camp trip with my 2 - six volt battery system. If I'm kind of facing south and get any significant sun (2-3 hrs) I'm almost fully recharged. Note that pre 2021 320s and 400 models have at least 30 more (potential) watts available as nuCamp changed the panel on these. I don't have experience with the slightly higher wattage panels but I know I don't see any charging in trees and facing north. Hence why I'm building a "needs based" remote system and for use this winter.

elbereth

The Norcold NR740 in the 320 CS-S (a 2-way DC fridge) is spec’d at 3.6A when running.  The fridge cycles on and off, but it runs about 25% of the time or less, so approx 21.6 Ah per day (3.6 A x 6h run time).

Between all of our draws (liberal light, fan, water pump usage) we use somewhere in the 35-40 Ah/d range.

We have a 100W solar suitcase that we can move to face the sun through the day, and even with that, in Minnesota, my best charging day so far according to the Victron Connect app has been about 35 Ah.  Most days I get closer to 15 Ah, some less.  So I’m usually about net minus 20 Ah/d, give or take.

With my dual 6V, 235 Ah setup, 3 days of boondocking is a piece of cake.  I don’t even need to bring the solar panel along.  

@Lloyd, your bigger trailer is going to have bigger draws for lights, fans, water pump, etc.  But if you’ve got the stock dual 6V 220 Ah batteries and start out fully charged, you’ve got around 110 Ah to work with, and especially if you’re frugal with power usage, 3 days should be do-able.

Lloyd

Thanks for the input, very helpful and reassuring.

Kentsb

MarkAl said:

@Lloyd you didn't state your model / year but with my 2021 320S w/ factory solar (2 way frig) it's useless in the trees and facing North. That said I can easily get a 3 day dry camp trip with my 2 - six volt battery system. If I'm kind of facing south and get any significant sun (2-3 hrs) I'm almost fully recharged. Note that pre 2021 320s and 400 models have at least 30 more (potential) watts available as nuCamp changed the panel on these. I don't have experience with the slightly higher wattage panels but I know I don't see any charging in trees and facing north. Hence why I'm building a "needs based" remote system and for use this winter.

Mark,

I have a 2021 320 Css Boondock and Mine has a 12V only fridge. I observed the frig will cycle on and run for 30 seconds or so and shut off. It does this about every 5 minutes. Does not make sense. We were in very warm weather so probably 75 to 80 degrees at night. Pretty much took the battery down to the point it stoped trying to cool. Does not sound right. What is the behavior of yours durning the night?

Marceline

Kentsb said:

Mark,

I have a 2021 320 Css Boondock and Mine has a 12V only fridge. I observed the frig will cycle on and run for 30 seconds or so and shut off. It does this about every 5 minutes. Does not make sense. We were in very warm weather so probably 75 to 80 degrees at night. Pretty much took the battery down to the point it stoped trying to cool. Does not sound right. What is the behavior of yours durning the night?

Depends on the fridge temperature setting, but yes, it does cycle on and off. If it consumes an avg of 2.5amps/hour that’s 30amps over 12 hours, which is a bit bite out of a 75aH battery. For many of us with a 2way fridge the solution is more battery capacity. 

(The electrical gurus out there are welcome to fix my math & nomenclature)

CharlieRN

I'm far from an expert in any of this and in fact much of what I know comes from info gleaned from this site and specifically from a thread I started a few weeks back. As the warning labels often say: "This information is believed to be accurate, but is not guaranteed to be so and should be used with caution." 

With that said, I think the new 320 uses the Cruise Elegance 65 refrigerator. The Isotherm website states that “power consumption (W/24h) is 360" for the CE 65. That's a bit ambiguous, but my interpretation is that that Isotherm is saying the refrigerator uses 360 watts over the course of a day, or 360 Wh. That would mean the refrigerator's current use is 30 Ah (360 Wh / 12 volts = 30 Ah).

It would be great to see how the factory estimate compares to what T@Bers actually experience with the CE 65.

Verna

I had a 2019 T@B 400 Boondock Lite and camped in a dispersed campground in Southern Arizona with no electricity, just water at my campsite from December 16, 2018 until April 6, 2019. I had no electricity, only 200 watts of Zamp flexible solar panels on the roof and the stock dual 6 volt AGM batteries. I did not run out of battery power during this time. Not only was I using the inside 2-way fridge, I was also using my 50 qt ARB fridge/freezer on 12V from the 400,  watching TV in the evening through my DISH satellite and charging my Kindle, iPhone and iPad. 

I always had plenty of power. No, I do not know the specific model of 2-way fridge nüCamp used in my 400. 

I have a 2021 T@B 320S Boondock on order with 210 watts of solar and dual 6 volt AGM batteries. I expect the same results from the 320 as I had on the 400.