One other concern I've read about is that above certain elevations, when the air gets thin. If the circuit boards aren't coated or designed correctly. They can arc and destroy themselves. I believe Schneider equipment has a lower altitude rating for this reason. This is what I've read on other...
There is one other thing that you need to keep in mind. If you put your panels in series, watch the maximum input voltage.
As a fellow cabin owner just south of International Falls, it gets darn cold here! As the temperature drops, the panel VOC rises! I have a 48v system with the panels wired...
A couple more points to think about,
1)A 100w panel doesn't usually output @ 100%. I'd figure 80% (80w) at best.
2)Did you figure anything for ac?
3)Electronics don't run at 100% efficiency. Various efficiencies for various types.
It sounds like you are on the right path, and have a...
I thought it was very cool also! When I found it, I was looking for a solution for my cabin. Most operate on ac like the one below. Although it has a dc motor. A person might be able to run on dc with a converter. But a lot more $$$...
You might want a charger that has temperature compensation for charging voltage. The colder your batteries the higher the charging voltage. Some batteries limit the charging voltage. All depends on the battery manufacturers recommendations.
Ed
I think a couple 6v golf cart batteries would work for you. In Minnesota, we currently use them in our cabin. As long as they are charged, they won't freeze. Cold lead batteries last longer than hot ones. You could build a taller insulated box that isn't totally airtight. That would allow the...
You could use something like this also. A little pricier, but would only need one panel, and could be under battery voltage. They do make one for lithium...
If your looking for a SCC I believe the Midnite Kid can handle it. 30a from somewhere around 12v all the way to something like 72v. Marine rated.
https://www.midnitesolar.com/pdfs/10-268-1_REVT_Kid_Manual.pdf
Thank you both, timseletric and wpns, for your response. I think I understand both of your responses. And I agree that there is no motivation for a battery builder to make the certification test more difficult. It's sounds like a nail biting process as it is. I will plan accordingly.
As far as...
I think something like this would work. You may have to put it on a timer because of the high cfm. But you would recover some of your heat and it's 12v. I haven't used one and I don't know the quality of the product.
https://balrvproducts.com/product/25110-air-port-fresh-air-exchanger-obsolete/#
Not sure how big your looking for. But I bought a dc ceiling fan from Home Depot. I think it is 68" in dia. On low it uses about 3 watts. On high I believe around 30 watts. 9 speeds total. From 3000 cfm on low and something like 12500 cfm on high. I verified the low power draw at lower...
This may also be an option. I haven't used one of these before, but look promising. I've seen used ones on ebay. They are Bluetooth, custom charge profile, and lithium compatible. They make other sizes also...
One thing that I haven't read in the post is the VOC of the panels. My 48v system is located in Northern MN USA. We often get -40F / -40C (same temperature) or colder. The record is -62F and is only 20 mile away as the crow flies. I've read that in order for a mppt charge controller to work...
I do like the way fromport has separated the positive/negative from each other. Also, that they are on the "outside" of the pack. This can reduce the chance of shorting out the batteries when installing the cables.
It can also be slightly modified if you want the posts closer for running cables.
I saw that also. Is it 7" or 12" minimum clearance? The way it is worded. 7" meets fire code. But you need 12" for normal operation. So it sounds like 12" minimum. ???
My wife's cpap makes all the led lights blink in our cabin. It is a small draw, (50w ?) but makes the whole cabin blink. To minimize the effect, I played with the output voltage. The way it was explained to me is that the inverter and power transformer resonate with each other. Could be...
I agree. Here is a link for an example I was looking at. Voltage drop shouldn't be a issue.
https://www.amazon.com/12V-24V-Daylight-Voltage-Lighting-Interior/dp/B07Z219ZDP/ref=mp_s_a_1_5?crid=OTYBAIYS29J&keywords=12-24v+led+light+bulb&qid=1670435278&sprefix=12-24v+led+light+bulb%2Caps%2C308&sr=8-5
I haven't kept up with this post, but I have a year old picture of a Home Depot fridge that kinda impressed me. I was there a few weeks ago and it appeared to be still available for the same price. Around 11 cubic in size. Sorry about the quality of the photo.
One question I have for the OP. Your original draw figures of 40 w X 20 hrs, etc. Did you also include the inverter idle power consumption? My Victron inverter uses 15w per hour. 15w X 24h = 360w
Some use 40w per hour 40w X 24h = 960w
On a small system these extra details matter. On a large...