Refer DC Voltage Cutoff Setting

[JDub]

So I purchased a 12v Wynter fridge a few weeks ago and I've just received a GOLABS Li4 power pack with the primary purpose to run the refer. Reading up on the GOLAB - it has a DC cutoff that's set at 11.8 v. The refer has an adjustable voltage cutoff in the DC power mode. It's currently set at 12.2v. Is this a sufficient safety margin to prevent damage to it in the event of voltage drop or should it be set higher at perhaps 12.3 or.4?

Thanks in advance!

 

[tx2sturgis]

You will only get a few hours of use that way, what is your plan to recharge the power pack?

To answer your question tho, yes you will need a bit of 'headroom' between the two values. About a half a volt should be about right, meaning the fridge should shut down before the pack is fully depleted.

You might want to do some testing with canned drinks before you fill the fridge with $50-$100 (or more) worth of perishable food items.

 

[JDub]

I'm in the test process right now. Got the refer set at 45 degrees and I fully charged the power pack before connecting the DC power (it also has an AC outlet with 300w of pure sine current. Now I'm just gonna let it sit - tic toc... Another poster stated that they had the same power source and connected to their 12v fridge , it ran it for ~ 48 hours indoors according to him.

Don't know what the specs on his was but I've got the 45qt model Wynter. I've set the voltage cutoff on it higher than I think I need just to have a safety margin starting off. It's a very nice piece of kit. I'll post the results when I get them. I've got a 100w 18v flexible panel array that will direct charge the power pack without a CC coming Mon and I can always use the vehicle power plug or my inverter generator to fully charge as well.

I just want an alternative to having to carry along my heavy solar system that has way way more capacity than I need for just vehicle camping.

Cheers!

Cheers!

 

[tx2sturgis]

48 hours of total time could be around 12-24 hours of ON time, compressor running. It depends on ambient temps and how cold the stuff is that you put in the fridge. 

But yeah, sounds about right. And if your plan is 2 or 3 days camping, then it seems to me that an ice chest might be the better option.

 

[JDub]

An ice chest is what I usually use for short term trips - either that or my old Coleman 12v cooler. I'm outfitting for trips that last 2-3 weeks in just my jeep without the tent and associated stuff. Later this summer I'm planning on pulling the trigger on a 17" teardrop TT and most of what I'm getting now will go into it. I'm used to a very minimal lifestyle camping (holdover from my days in the mil) and that TT is going to be like a palace to me!

Cheers1

 

[B and C]

40° F
Keep the refrigerator temperature at or below 40° F (4° C). The freezer temperature should be 0° F (-18° C). Check temperatures periodically. Appliance thermometers are the best way of knowing these temperatures and are generally inexpensive.Feb 9, 2021

Are You Storing Food Safely? | FDA

 

[jonyjoe303]

I would keep it at 12.2 volts, or even lower if it went lower. Your going to get voltage drop everytime the compressor goes on, you don't want the fridge to shutoff when that happens.
From my calculations the golabs power station has a 23 ah battery in it. I have my fridge (joytutu 26L) set to 26f degrees and it uses 18ah per 24 hours. I also use to have a edgestar 43L which is similar to the whynter and that one use to use 26ah per 24 hours when set to 40f degrees. You should at least get 1 day of run use with your fridge at the temp you have.
Don't worry about the golabs battery running too low, its lifepo4, it can be cycle to zero percent hundreds of times. It has a built-in bms that will stop putting out power if the battery gets too low.

One thing since your running tests, if the fridge compressor starts cycling back and forth its probably because the voltage is too low or unstable (the golabs doesnt have a 12 volt regulated output according to some of the reviews I read) . I encountered unstable voltage from my 220ah lifepo4 that was causing problems on my fridge. I had to use a dc-dc boost/buck converter to fix it.
If you encounter unstable power, its an easy fix, doing what I did. Using a boost/buck converter keeps the power very stable, I have it set at 13.4 volts and when compressor comes on it only drops to 13.2 volts. Its just something to look out for.

 

[JDub]

^^^

Thanks for the insight! Very useful. Currently the power pack is still hooked up to the refer and it's maintaining 12.9 - 13 v except when cycling as you noted. Drops to ~ 12.2v. It's been hooked up for 24 hours now and I've lowered the temp in the refer from 45 to 40. It's currently reading 35 inside w 60% of charge left on the GOLAB. I've actually been researching DC to DC power regulators for use with all of my equipment but all of the one's I'm interested in are wire in's. I'm looking for a plug in and unplug variety so I can use it with all of my 12v equipment. Any suggestions?

Cheers!

 

[MotorVation]

The cigarette style plug on the Whynter causes a voltage drop as well. I know you don't have this option right now but I cut my plug off and attached it directly to the batteries with ring terminals. Just giving you a head's up

 

[jonyjoe303]

I had to build my own because with a fridge you need about 13.4 volts, you can use lower but in my tests I ran with my fridge 13.4 volts was the one where the fridge ran with no problems. Even when my li-ion 11.1 volts powerbank went below 10 volts the fridge kept running uninterrupted.
They sell 12 volt voltage stabilizers and I have one which I tried but it didnt work for me, I think because the output voltage was low, right at 12 volts.

The boost/buck I use is 2 converters, the boost raises the voltage to 18 volts, then that goes into the buck converter that drops it to 13.4 volts. Doing it this way you keep all the amps, which is what you want especially on a fridge which might peak at 6 amps when the compressor starts. I been using my boost/buck converter nonstop 24/7 for the past 4 months powering my fridge, the power it uses is insignificant (about 50ma). The fridge hasnt stop even once, before the compressor was cycling back an forth almost every other night when the voltage on my batterybank started to go low. The fridge loves that 13.4 volt dc power.

Once you set the output voltages on the boost/buck converter its plug and play. You never have to mess with it again.

 

[JDub]

^^^

I've been looking at similar boost buck units on Amazon and they're very reasonably priced but I'd like to get a plug and play stand alone unit if I can so I can switch it around with my other equipment instead of wiring each separately. I may have to do what you did and jury rig one with a cigarette lighter plug on the output side and a plug that fits the 12v terminal on the GOLAB.

Incidentally, the refer lasted 45 hours on the GOLAB. I unplugged it an hour ago since the input voltage had dropped to 12v while cycling with 24% left on the power pack. It's held a pretty steady 12.8-13v while not cycling and ~ 12.2 - 12.4 v while it's running almost the whole time but once the power unit dropped below 25% it started to drop in input voltage and I don't want to risk damaging it. I think it would have lasted to 48 hours easy if it weren't empty. Next test run I'll fill it with adult beverages and let's see how long it goes... I really like this power pack. I'm expecting the flexible 18v solar panel array tomorrow so I'll be able to give that a whirl.

Cheers!

 

[JDub]

The cigarette style plug on the Whynter causes a voltage drop as well. I know you don't have this option right now but I cut my plug off and attached it directly to the batteries with ring terminals. Just giving you a head's up

I noticed that, I had the small DC terminal cord with the cigarette plug plugged into the refer but then I tried the big 12v plug which drew it down at a little faster rate...