Fuse size for 2nd battery

Just got my fridge in, starting the stress testing now;

 

53 or 42 quart?

I'd be interested to hear your impressions.

Do you have a multi-meter? I'm curious how many amps it draws, and how frequently is cycles at a given temperature.

 

Its the 53. I actually kinda like it, its not too big but large enough to pack some frozen meat and keep vegies or whatever cool. Personally I would have designed it for more room to the "fridge" section but its good enough.

Yeah I have a multimeter but I wanted to check out what it could actually do and in what kind of time frame if that makes any sense hahaha. The first night when I first fired it up it read ~74 F, I set it to 32 and let it run all night plugged into my house outlet. I recall when I woke up I saw it round 45ish, the bottles were not frozen just cool. I let it settle down for a day or two and decided to set it to 0.0 degrees F. About a day and a half all bottles in the freezer section were completely frozen and the fridge bottles were just cold.

I understand what your concerned about with the current draw and how many times it cycles. I'll update this as I go.

 

Still trying to decide which size/type battery to go with for my second battery lol.

 

If it fits your budget, I'd get something like this.

https://www.monsterscooterparts.com...er-chair-rv-marine-solar-storage-battery.html

I'm still trying to decide if I want that battery or dual 6V golf cart batteries for my camper when it comes time for replacement.

 

Oh ok. So question, whats the difference between that battery and say a AGM or gel pack from my local auto parts store?

 

Nevermind, some quick googling and I get it now. Guess Im off to my local marine or rv shop to look around.

 

Good luck, sailor.

 

You're going to see marine/RV batteries rated on "Reserve Capacity" which is the number of minutes the battery can deliver 25 amps before it drops below 10.5 volts.

You'll find solar system (and other types of true deep cycle) batteries rated in Ah (amp-hours). A 100Ah battery will deliver 1 amp for 100 hours, 2 amps for 50 hours, 3 amps for 33.3 hours, etc.

In order to compare the two types of batteries, you need to convert "reserve capacity" to Ah.

Here's a good site for that: https://sciencing.com/how-8681870-convert-reserve-capacity-amp-hours.html

Here's another good site to help you calculate your power needs: https://www.caravansplus.com.au/guides/calculating-how-big-your-battery-needs-to-be-a-44.html
(In fact, if you scroll down the page a bit, it gives a scenario for running a fridge/cooler like the one you just bought.)

The take-away is that the solar/RV deep cycle batteries are superior to the "marine/RV" batteries.

Case in point: if you take the scooter/solar battery I linked to above, and compare it to a good "marine/RV" battery like this one, you see the scooter/solar battery is rated for 100 Ah, and the marine/RV battery is rated for 62.5 Ah. They both cost a little over $200 and the scooter/solar battery is truly designed for slow, constant power delivery like we need for the application we're talking about. It's really a no-brainer.

 

Ahhh good to know, thanks for that bit of knowledge. Thanks for links too, I took a quick look and theres tons of information I need to read through haha. Is this the battery you were talking about that you sent:

$189 UPG Universal Power Group 12V 100Ah Solar Wind AGM SLA DEEP Cycle VRLA Battery 12V 24V 48V

https://www.amazon.com/Universal-Po...s=Universal+Power+Group&qid=1616135172&sr=8-1 ? Its cheaper through Amazon, saves you ~30$. I looked around and yeah it looks like you found (if this is the correct one) the most cost effective one.

 

Yeah, it appears to be the same. But to be clear, we don't know who makes these batteries, and to what specifications. We know they're made in China (which doesn't necessarily mean low quality), and that they're "generic" -- meaning there is no name brand. I might be more inclined to trust a brand like Renogy because they're a pretty well-respected solar company. But given the price difference, it may be worth rolling the dice with the cheaper/no-name battery to get started in all this. It's only $180. If it lasts 6-8 years instead of 10 years, it's still given good service at a reasonable price.

 

Thats true, they seem to look the same but might not be built to the same specs. I'll have too look at other options just to compare, I'll update as I figure out which one I decide to go with.