diy solar

diy solar

Hello. I’m new here. 1st post. Looking for general input for electricity… remote cabin

I have an email sent to clarify. Their,website,says it uses charging current. Battery is protected from discharging, and cold charging.

I guess it really doesn’t matter as long as the battery polices itself. I can leave it all connected. But having said that, there’s no harm in charging the battery to about 75% for the winter and then disconnect, and hook back up in the spring.

for the amount of time anyone goes,out I’m the winter, just run the generator.
 
MPP Solar units also will charge with the inverter switch off.

Pretty sure Will’s setup has a big T class fuse from his busbar to the inverter.
I’ve watched a couple AIO videos by will. He does not use a fuse, and specifically says because the lfp has it’s own, that it’s not needed
 
Further to battery heater:

trophy has been charged to 75%ish. Disconnected. BIL comes out for a winter weekend. He turns on the battery. They start to heat. Will there be condensation? This is bad?
 
I think you are over thinking it. I don't know why you would pay so much for the Samlex when better, cheaper solutions exist.
We gave you multiple options for a 24v, 2000-3000watt AIO from MPP, Growatt and Midnight Solar. These were designed to do exactly what you are looking for, a low power off grid solar setup. LPF is the best battery for your setup, it's been running 1000's of systems like this for years. It's limit is low temp charging, which you see OK working around. I think you misunderstood about the heating. The recommendation was to build a small heated box to keep the batteries warm enough to use year round. That is something you could explore down the road. I feel you are hung up on just how easy the newer tech has made it. Yes you get a MPPT, pure sin wave inverter, ac battery charger and transfer switch all in one little box for under $600. Add $600 for 2500 Wh of LFP battery. A high estimate is 1$ per watt for panels, lets say 600w.
Couple hundred for odds and ends and for $2000 you have a nice little system, and it can be upgraded with more battery and panels if you find your needs change.
So the more I research, the more the AIO makes the most sense. This video is pretty much what I had in mind for hook up. “Plug” in the cabin. If needed plug the cabin into the genny. I just need to make sure I buy an AIO with good “gas mileage”, aka low consumption.

id still bypass the internal charger and use a dedicated charger.

I do like the portable version of this. I could take it home for the winter and it’ll do standby duty for power outages.

now the question is 24, or 48v?
 
I heard back from Dan @trophy. I sent the email @5:00 last night and he apologized for taking so long to respond, lol. (He responded this morning, which I thought was pretty exceptional).

he did confirm that the trophy heaters do not use their own power to heat, they only use charging current. Once the battery is proper temp it will begin accepting charge.

just waiting to hear back as to proper use/storage for our situation.
 
Its normally not like me to look at safety first but 48V can kill you, 24V not nearly as likely. If you have "others" potentially messing with this, i'd consider this point.
100% valid point

having said that my brother in law would be the only person out there. He’s not the type to play around. And we COULD just disconnect for the winter but, valid point sir!
 
Well, the whole reason I re-designed my camp's setup is because Trophy batteries only come in 48v, and it's getting harder and harder to find rackmounts that DON'T come in 48v. Plus 48v is good for anything from 3Kw up past 12Kw so expansion is an option.

I heard back from Dan @trophy. I sent the email @5:00 last night and he apologized for taking so long to respond, lol. (He responded this morning, which I thought was pretty exceptional).

he did confirm that the trophy heaters do not use their own power to heat, they only use charging current. Once the battery is proper temp it will begin accepting charge.
Good to know! I sit corrected. ?

trophy has been charged to 75%ish. Disconnected. BIL comes out for a winter weekend. He turns on the battery. They start to heat. Will there be condensation? This is bad?
You could email Trophy about that but I can't see that it would be an issue they overlooked. The battery is going to heat pretty gently and condensation really prefers drastic changes in temp to form. Doesn't hurt to ask.
 
I think your situation calls for 24v. The larger 48v systems have double the standby consumption, which requires more battery and PV. Something to consider is a 2500w 24v inverter is going to exceed 100 amps of many BMS's. Chins makes a 12v self heated battery (works off charge current just like trophy) There is a 250ah with 200a BMS. Put 2 of these in series and you would be all set.

One thing I don't understand is why you wouldn't use the AC charger function of the AIO? You can program the charge current to work with your generator capacity. Using a standalone seem unnecessary.
 
I think your situation calls for 24v. The larger 48v systems have double the standby consumption, which requires more battery and PV. Something to consider is a 2500w 24v inverter is going to exceed 100 amps of many BMS's. Chins makes a 12v self heated battery (works off charge current just like trophy) There is a 250ah with 200a BMS. Put 2 of these in series and you would be all set.

One thing I don't understand is why you wouldn't use the AC charger function of the AIO? You can program the charge current to work with your generator capacity. Using a standalone seem unnecessary.
what does “exceed blm” mean? The max current in/out? I.e I could use charging current As a guide?

yes I,can program charger current. I just thought more efficient to use seperate charger. I’ll need a,seperate charger anyways as I’d take my battery home for the winter.
 
Well, the whole reason I re-designed my camp's setup is because Trophy batteries only come in 48v, and it's getting harder and harder to find rackmounts that DON'T come in 48v. Plus 48v is good for anything from 3Kw up past 12Kw so expansion is an option.


Good to know! I sit corrected. ?


You could email Trophy about that but I can't see that it would be an issue they overlooked. The battery is going to heat pretty gently and condensation really prefers drastic changes in temp to form. Doesn't hurt to ask.
based on my set up Dan recommends taking the battery home for the winter and charging it every 3 months. Condensation “could” be a problem, but also said the 100 watts heats gently. I could wrap the battery in plastic.

honestly solar for the summer. Genny in the winter for BIL. He’s been doing it that way,for years, and he doesn’t go out more than a handful of times.
 
what does “exceed blm” mean? The max current in/out? I.e I could use charging current As a guide?
Inside a LFP battery is a controller called a BMS that balances the cells, shuts off charging when too cold, and limits the discharge current among other things. Most bog standard LFP batteries have a BMS that's limited to 100a of discharge current at whatever voltage. So if you have a 12v 100Ah battery with a 100a BMS, the maximum it can discharge is 12v * 100a = 1200w of power. For a 24v system with 100a BMS batteries that would be 24v * 100a = 2400w maximum power. If you connected that to a 3000w inverter and loaded it up running the hot plate, the hair dryer, the TV, and the MargaritaMaster-9000 at the same time the BMS's would shut off the batteries output at 2400w before your inverter could reach its peak 3000w.

Most rackmount batteries are 48v but have that same 100a limitation, but 48v * 100a = 4800w of power which is more than enough for your 3000w inverter, but not enough to feed a 6000w inverter.

The ways around that are to either A: find a battery that has a 200 or 250a BMS built in doubling your wattage capacity (24v * 200a = 4800w, 48v * 200a = 9600w) which are a little more difficult but still available, OR B: get multiple batteries to help spread the load (2x batteries * 24v * 100a = 4800w, 2x batteries * 48v * 100a = 19,200w) which is what many people end up doing, especially if they're connecting bog standard 12v batteries together to get up to 24v or 48v systems.

I think your situation calls for 24v. The larger 48v systems have double the standby consumption, which requires more battery and PV.
Not quite. The split phase units like the MPP 6048 units are double the standby of a MPP 3048 because it's just 2 of the 3048's in the same box. The 6Kw units draw about double what a 3Kw unit draws, but EG4, MPP, and Growatt 3Kw-ish units all draw about the same standby wattage. It's mostly a factor of how big the inverter is, not the voltage base.

You could do 24v and a 3Kw inverter, but you wouldn't be able to use Trophy batteries (or almost any rackmount style) as they're only available in 48v and if you ever wanted to upgrade your system you'd have to change battery setups to 48v to get over 3Kw for the most part.
 
Inside a LFP battery is a controller called a BMS that balances the cells, shuts off charging when too cold, and limits the discharge current among other things. Most bog standard LFP batteries have a BMS that's limited to 100a of discharge current at whatever voltage. So if you have a 12v 100Ah battery with a 100a BMS, the maximum it can discharge is 12v * 100a = 1200w of power. For a 24v system with 100a BMS batteries that would be 24v * 100a = 2400w maximum power. If you connected that to a 3000w inverter and loaded it up running the hot plate, the hair dryer, the TV, and the MargaritaMaster-9000 at the same time the BMS's would shut off the batteries output at 2400w before your inverter could reach its peak 3000w.

Most rackmount batteries are 48v but have that same 100a limitation, but 48v * 100a = 4800w of power which is more than enough for your 3000w inverter, but not enough to feed a 6000w inverter.

The ways around that are to either A: find a battery that has a 200 or 250a BMS built in doubling your wattage capacity (24v * 200a = 4800w, 48v * 200a = 9600w) which are a little more difficult but still available, OR B: get multiple batteries to help spread the load (2x batteries * 24v * 100a = 4800w, 2x batteries * 48v * 100a = 19,200w) which is what many people end up doing, especially if they're connecting bog standard 12v batteries together to get up to 24v or 48v systems.


Not quite. The split phase units like the MPP 6048 units are double the standby of a MPP 3048 because it's just 2 of the 3048's in the same box. The 6Kw units draw about double what a 3Kw unit draws, but EG4, MPP, and Growatt 3Kw-ish units all draw about the same standby wattage. It's mostly a factor of how big the inverter is, not the voltage base.

You could do 24v and a 3Kw inverter, but you wouldn't be able to use Trophy batteries (or almost any rackmount style) as they're only available in 48v and if you ever wanted to upgrade your system you'd have to change battery setups to 48v to get over 3Kw for the most part.
I’ll never worry about tripping the bus. Cabin is 1 single circuit. Once I set up an ac panel I’m going to put the cabin on a 15 amp breaker to protect the wire.

im looking to power starlink, poE acces point. Cpap, some lights, a smart Tv (Orr Tv and Apple TV) and,charge our iPads and phones. Don’t think I’ll ever need. 6000w inverter
 
Will there be condensation?
Condensation happens on the cold item not the warm item
now the question is 24, or 48v
id use the 24V for the safety reason mentioned; as well as you have some failure proofing with four 12V batteries.
the more the AIO makes the most sense.
Just need to plan adequate solar to handle the idle consumption imho. I am not highly likely to have a predilection for not-component equipment that I depend on but I love my tiny 1012LV-MK; the built in charger and the automatic functioning eith programmable parameters is just easy. Poor winter solar is where it “bothers.” Not an issue for you.
 
Condensation happens on the cold item not the warm item

id use the 24V for the safety reason mentioned; as well as you have some failure proofing with four 12V batteries.

Just need to plan adequate solar to handle the idle consumption imho. I am not highly likely to have a predilection for not-component equipment that I depend on but I love my tiny 1012LV-MK; the built in charger and the automatic functioning eith programmable parameters is just easy. Poor winter solar is where it “bothers.” Not an issue for you.
Battery is cold. As it warms… condensation. Maybe. Confirmed by trophy.

24v safety totally valid.

planning for higher self consumption kinda valid, kinda not. Power saved is money not spent. Not to mention the point of solar is “green” reuse, recycle, etc. it’s cheaper to not have to power something than to make allowance for it.

but yes, that AIO form factor, hard to beat.
 
Alright I’m now confused about auto transformers and AIO units.

a 120 AIO come with a neutral right? If I buy a 240 AIO it only has a black and red, no neutral and I’d need a transformer?

or do I have this wrong? We don’t have 240 at the cabin and I don’t see the need? (Maybe ac but I thought ac was a no no on solar)
 
If it's 120/240 split phase then it will have a neutral . You don't have to use 240 ac with split phase but it's there if you need it.

Yes, AC would be very taxing on a medium sized PV system. Not that you can't use it but if your battery bank will get depleted in short order or your PV can't replenish your batteries fully the next day then your system shouldn't be expected to run AC. Friends in my area are running 1 ton Mini Split AC on 2000 watt inverter generators. I run my 5000 BTU window unit at night on my 2,000 watt generator using about 3/4 gallon of gas.
 
Alright I’m now confused about auto transformers and AIO units.

a 120 AIO come with a neutral right? If I buy a 240 AIO it only has a black and red, no neutral and I’d need a transformer?

or do I have this wrong? We don’t have 240 at the cabin and I don’t see the need? (Maybe ac but I thought ac was a no no on solar)
Not too long ago when the AIO's were first hitting the market they were all built for EU power which is 220v/N and to make them work with the US electrical system you needed an autotransformer that would kick that 220v/N and split it into 120v/120v/N since that's how our power system works. Since then many companies have come out with units that will do the 120v/N or 120v/120v/N that the US power system uses so there's no need for an autotransformer anymore.

In short, don't worry about it and just get the unit that works with your local power system.
 
Just some more random thoughts after many hours of reading, watching, learning.

im not interested in a cheap, Chinese made AIO unit. Will has had issues, and I just want something that will work, work reliably, and no fuss. If I have to pay more then so be it.

im leaning towards either a Morningstar based system (inverter/charge controller), and battery charger or possibly some Victron stuff (multipluss2 and charge controller). Likely I’ll go with Morningstar for no reason than I already have the suresine 300. It’s got a tank like build quality.

the only question now is how to size? I can’t “properly” size because there’s nothing normal about the cabin. It can go days sitting empty and require no sun, and it can be occupied for,weeks at a time with people staying up till 3am, watching Tv, and leaving lights on.

do I size for OUR needs? And when THEY use the cabin when the battery dies, it dies? (They can run off the genny?)
do I size for 24/7 starlink, 10,hours of Tv, and light on all night, and cellphones charging?

I honestly just need to power starlink (turn off when not using) let’s say 800 wh, 5 hours of Tv (750wh), c pap (60wh), and lights/iPhone,chargers.

im thinking 3 panels around 1400 watts, 1 trophy battery @5100 wh, and a charge controller that allows for future expansion (60A is,enough ?)

I know, this isn’t the “usual” way to do solar, but there’s nothing “Usual” about the place.
 
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