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Hello everyone, Western Pennsylvanian here, I just stumbled upon this site and it seems there are a lot of solar enthusiasts out there! Thanks for letting me join, I'm sure I still have a lot to learn and I look forward to every minute of it. :) As the title suggests, I have a 7 cubic foot...

Back when I first designed the system it had a couple problem days in late summer where it cut out. That was a deep cycle lead acid 100ah though and I had the cutout set pretty high. I also had a pwm charge controller and the roof was pitched west, not south! Any one of those improvements would...

Build a greenhouse around your hot tub and you get double the bang for your water heating buck!

October 2022 This Chinese FEENCE branded battery is available on Amazon for $279 with free shipping. For comparison Weize is currently $300, AmpereTime is $350. In the weeks since my purchase there is a new slightly cheaper battery by “IOD” that is selling for $259 but someone else is going to...

If your concerns are accurate, then post the detail of what you believe to be in error, along with a link/timestamp and what you propose is the correct info. If you're correct and there is an error, then this thread can be where that's solved. If you're in error someone will come along to...

That guy lost his **** during covid and bit the hand that had been feeding him. Specifically, he made his money selling people on his concept of urban farming, even calling himself The Urban Farmer. Then covid hit and he put out some videos calling Urban people worthless pieces of **** and...

I think we're all missing a big opportunity here. Someone with a chatGPT account should ask it what the deal is with the word "woke" and then paste its answer here. That would be pretty interesting on several levels ?

There are a lot of tradeoffs in designing I/O on circuit boards. The most accurate ones my company has made were 24 bit a/d converters with 1% resistors and even with them we had to calibrate each board on a bed of nails before assembling them. In our case the I/O was flexible so we had 2...

I have a similarly sized system on a greenhouse. The excess "dump loads" are put into heat when it's cold and ventilation when its hot or humid. If you like growing things, toss up a hoop house near the trailer and have at it :)

A century ago people filled their ice houses in the winter and year round they used that ice to feed their kitchen ice boxes. Call me lazy but I find electric refrigeration to be so much simpler.

Have you considered a sterling engine geared up to spin an alternator?

California is going to do what California is going to do. Not all of their ideas catch on in the other states

Efficiency? I prefer a single battery bank to maintain. But I'm all about a charge controller per string and I'm all about an inverter per load. Toggling inverters on as needed leaves you with no losses when the load is off, that's true efficiency. I'm just wrapping up this project:

I'm almost done with the third generation power sled for the fridge and I thought it worth an update. I've added a better controller/brain and that has allowed me to make the whole operation much smoother. There are now 4 modes based on battery level- Full Power, Basic Power, Reduced Power...

Off grid systems can be pretty safe in this respect, even ones built by folks you might not want to trust. But if you're grid tied there are a myriad of possible issues you can't easily sidestep. The smart power meter is a glaring example.

Still going strong. The battery heating experiments have been coming along nicely. I've found that with the foam insulation I maintain about 2° rise above ambient for every watt of power I apply to the heater. I have a 6w heater so in theory I don't have to tell the CC to turn off unless...

I'm not here to give advice. That said, is there a per-panel micro-inverter offering that shuts down when grid power is out? That would solve two issues, for one you could buy one per panel at your leisure as you add to the system. You'd likely be sizing the panels for the micro inverter...

In 2s 2p you'll need a charge controller that can accept 150v on cold days. For current you'll need to account for 28A on the combined wires. 14A is the max current on the non-combined strings. I'd put a 30a breaker on the series and use 4awg if you went that setup.

This thread is almost exactly what I've been working on! It seems I wandered upon it a little late as I've already cast the first stone, so to speak but it's only the first test cast and I intend to do more anyway. (That said, In my scenario I'm trying to heat concrete with an embedded...

At one point someone offered a crt-based TV with a VCR and a DVD player inside of it. For reasons unknown, they sold a lot of units and other manufacturers followed suit. In the decades since I've struggled to understand the thinking of the buyers. It seemed obvious that once any of the...

To offer a simpler explanation- You need to match the impedance of the source and the load to maximize power. We older folks are well versed in this stuff because back when we all had hi-fi stereos this came up a lot. With sound systems you need to match the impedance (resistance) of your...

It's not a temperature thing, that's what current rating protects against. This is more of a high pot thing where the insulation could cease to be effective in preventing it from shorting against any metal surfaces it's laying up against.

That is exactly right. :)

In solar-land the "best in class" fridge is a chest freezer run at 38°

To be clear- you'll now be in charge of the temp in the freezer. Before you take over that control (before wiring the relay in the back of the stat to the inverter switch) I would suggest that you power up the thermostat and watch what it does for a few days. If you drape the temp sensor in...

McKravitts- I designed the very circuit you're describing. I am using a Tracer 2210AM charge controller which comes with a high temp cutoff but no low temp cutoff. The native thermistor for my device is a 47k ntc and I've bought a $5 thermal switch to pull an 8k resistor into the circuit...

I assumed Giant Spaghetti Monster

You can get a 0° switch but these are generally fairly cheap devices so you'd have to test every one. If it triggers at 31.5°F it's probably still in spec for the part but it would be useless for our purposes ;)

I fixed that drawing for you (attached below). Why it showed lightbulbs generating energy is beyond me!

If you want the most redundant, hard to kill, no single point of failure setup then you should consider multiple charge controllers (one per string) and multiple inverters, (one per circuit). I'd still stay with 48v though. Five 2000w 48v inverts would cost you around a grand and any one...

The last thread like this one went off the rails really, really quickly. In the hopes of keeping this one grounded in reality here is the text of the law in question (which has been signed and enacted): https://www.congress.gov/117/bills/hr5376/BILLS-117hr5376enr.pdf Here is the clean...

Before you add solar panels to your system have you considered making your current setup run more efficiently? Your design appears to keep the inverter on all the time. Spend the $15 on an inkbird style 12vdc digital thermostat and wire it's cooling relay output it in series with the go signal...

In that link they're not crossing streams, so to speak. The Grid AC and the CyboInverter AC are powering different elements on different circuits within the water heater. The utility has no business having or needing a disconnect on a device that's not connected to their grid AC.

If you have a voltmeter you can check to see if it's a dry contact output. If so, it will have continuity across the two pins of the load port when it's on and no continuity when it's off. If it is a dry contact then you wire power into one side and when the load port is on that power will...

Can we back up for a second here? How many watt hours is your house bank and how many watt hours is your combination inverter device? If A is comparable or larger than B then all you need to do is plug a 100vac battery maintainer into your combination device and hook the DC cables onto your...

These pavilion lights are (from memory) 20 or 30 watts and 12vdc. More watts, more light.

I've driven past the solar farms off of rt 36 for years. They put up all of the racks years and years ago and never put the panels on them. It always seemed odd to me that they'd put in so much money but not actually make it functional. It seemed like there was some sort of scam going on...

I'm curious to hear how your project works out. I have a 7 cubic foot chest freezer I run as a vegetable refrigerator but I designed the system for efficiency and not for future expansion as you have. Also I am in Pennsylvania where the weather is a lot cooler than Texas so I am sure that...

Charge each battery independently and fully and let them sit for at least an hour after the last one is removed from the charger. Measure the voltage of each battery and make sure that each one is within a tenth of a volt of 13.6 volts. Then and only then can you stack them back into your...

Just re-read the original post on this thread and realized that I offered a solution that's not waterproof or cutting edge. Oh well. They're great for dry panel to panel wiring anyway. ;)

Your response from the manufacturer (post 70) suggests that you have a CC that doesn't support lifepo4 natively and they suggest you manually set all of the parameters under the "user" configuration menus. So what battery type do you have it set for and what settings did you select under that...

Having a 240vdc system will be difficult to charge, maintain and use. If I had that specific pile of batteries lying around I'd either put them in a 20p configuration to make a 12V 180AH battery or I'd put them in a 2s10p configuration to make a 24V 90AH battery. There are plenty of charge...

Using the built in switch would require me to attach an actuator on the switch to be able to toggle it automatically via a timer or thermostat or clock or whatever. Connecting to it electrically is far simpler than adding robotics to the mix... ;-)

It seems that your hybrid inverter is grid tied and can also charge a battery if it wants to. You've told it to only use solar to power the battery for some reason. If you change that setting back to letting it manage the battery optimally would it put 1.5k to the grid at the same time it puts...

There's no guarantee that you'll be "allowed" to sell back 20 or 30 years from now. I'd think it would be best to design it to pay for itself as soon as possible without relying on selling any back. If you get that right you can consider it future-legislation-disappointment proof by slightly...

The voltage rating has to do with the insulation on the outside, it has nothing to do with the wire itself. I suspect its a very bad idea and I think it should not be done, But- I do wonder if anyone has bought a roll of shrink tubing and encased an entire length of wire to increase its...

Yeah, if the people who wrote the manual can't tell up from down I can only imagine how much they butcher the written word!

It's the roughly 70 feet of total transmission (20m) that makes me want to go bigger than the panel sized wires quoted above. https://www.altestore.com/diy-solar-resources/wire-sizing-tool-for-12-24-and-48-volt-dc-systems/

Unless you plan to put your power into their grid the only answer you should offer this person would involve sucking on a specific appendage. Followed by an armed escort off of your property. The power companies ONLY have any say over the grid and anything that connects to it. Anyone from...

Also, what is your solar situation? Changing battery chemistry won't allow you to gather more light. I'm concerned that if your load is much higher than your array can provide then the battery size/type you use doesn't actually matter.

You say you're losing power overnight without the lights on. Is there any chance that you've left the inverter hooked up to the battery around the clock and not simply when you need 220? Inverters chew through energy when they are powered up, even when there is zero load. If you have in...

What's your ventilation game-plan? What's your climate?

Did you put 160v into a 150v charge controller? If so it might be broken and this might just be how it acts now...

Are you saying you think this will force everyone who produces more than they consume to go entirely off grid?

Run all 8 in series and buy a 200a BMS. Your cells can presumably drain as fast as 1c which is 230a. There are a lot of 8s 200bms options out there with and without the bells and whistles of Bluetooth, etc. "8s 200A"

The best I've been able to achieve is: Energy- 160w panel Storage- 100AH 12.8v LiFePO4 Location- Pennsylvania Fridge- 7 cubic foot chest freezer Temperature- 41°f (nominal) It's been working since 2017 from spring through fall. In about 3 weeks I'll put it to sleep for the season since...

Nails, screws and wood keep the power sled out of sight. And trailcams are about but obviously they can only do so much. At some point you also have to hope people appreciate that feeding the needy is something worth leaving alone. I do wonder about the touch screen though. Probably not needed...

Buy or rent a thermal imaging camera (most attach to your smartphone). With that in hand you can tackle the top few insulation issues. That will give you a return on investment measured in days or weeks. Once you've hit the easy stuff insulation-wise you can get back to adding heat sources ?

I completely agree. However, I cannot forsee a situation where the batteries drop in temperature faster than the air in that compartment. I can get them to generate heat but not to appreciably sink any. The temp sensor is actually glued to the top of the battery case so it's probably closer...

Sure thing. This is what I'm describing:

I wouldn't lump switches in with busbars. Switches absolutely have a voltage rating as they need to accommodate for the greater possibility/inevitability of arcing at higher voltages. But yeah, other than a silly sticker from a manufacturer I don't think there can be a difference between a...

I do not. But there is a ton of info here on that topic. Take a peek at that forum and I bet you'll find exactly what you're looking for. https://diysolarforum.com/forums/bms-battery-managment-systems.23/

I'm trying to look closer at their design in the hopes that I can continue to reassure the folks I'm working with right now that our new system won't have a similar flaw. I've found a web page that purports to tell all about the system but the bottom of the two links goes to a file that's...

The short answer is that if there is a wire where you calculate that there should be 20 amps going in one direction and you also calculate that there should be 5 amps going in the other direction then in reality there are only 15 amps moving at all. The other 5 literally cancel each other out.

You're powering a desktop PC? They require 12vdc power and 5vdc power. A 12v bank and a DC to DC 5v regulator would power a desktop perfectly. No need for an inverter just to pump power into your computer's rectifier. Unless you're also running a monitor this seems like a slam dunk... Edited...

On the extension cord topic- Why not use a retractable cord? If you cut the ends off and install a male where the female is and vise versa you end up with a retractable cord that reached out towards house power instead of the other way around ;)

You're probably right. At least we're not moving back towards ammonia as the refrigerant of choice.

This is what a 1400w smoker looks like: https://www.bbqguys.com/smokin-tex/1500-c-commercial-series-electric-bbq-smoker

I use NiChrome for my Lifepo4 battery heaters. There are two things to keep in mind- Insulation and watts per foot. Insulation is important here, just wrapping the wire around a pipe will basically short it out and you'll burn something out. Always measure it with an ohm meter after...

I have piloted a solar powered boat built by the Bortons' company and it was really fantastic! https://www.solarsal.solar/ But of course they have a normal battery system and don't have the issues created when skipping that step. Like some others in this thread I am skeptical about...

Your 10 ohm resistors are built to dissipate a lot of heat (10w each). If you used one of those instead of the theoretical 100w resistor you end up with the following math: I is V/R so with a 10ohm resistor you'd be pulling 3.285V/10ohms or 0.3285 Amps. Power is V*I which is 1.0791225...

12vdc has more options than any other voltage. If you want bright, just choose a higher wattage. For example, a 10w 12vdc light (or string of lights) is REALLY bright.

Start by understanding the load your system needs to support. Specifically, measure the power draw of each of your freezers. That will give you a starting point for choosing the number of panels. Then you will need to decide how many sunless days in a row you will want to run the freezers...

Well it might well have 4 fets and not 2 (making it "modified" but either way it's never tripped me up. And 6 years later it still runs it whenever it calls for it. :) As for noise, out in that field it's hard to even hear it running, I have to put my ear to it to easily know.

Interesting. I'm just a few days away from testing my latest battery warmer and this topic is very much on my mind. This is the first time I've warmed a 5kwh battery so I've scaled up the wattage to 50W to accommodate the additional mass. I don't like the concentrated heat of the heat...

What's your actual objective, BroomJM? You have a 200w solar panel and you say you want to drive a 25w heater. Surely there's more to the story than that? If not, then why not buy a cheapy 25w (30w would be better) solar panel and drive the heater with that? The cost of the cheap panel...

"So, I can be generating 3.0kw from the solar panels, and when I connect the batteries, this generation figure drops " If you have no load then you are generating zero power until you hook up the battery. If you're not putting it into a load then you are not harvesting it at all. Edit...

It appears as though you were targeting 38-42° as your minimum battery temp. In retrospect would targeting 34-36° have allowed you to ride through long enough? Or was snow load a multiple day event that would have failed either way?

Do you have an ftdi chip (or equivalent) lying around to convert 485 pulses to USB serial port packets?

Very neat test. I've always danced around modifying the fridge itself as I've wanted that component to be plug-n-play and end-user replaceable. But your mods on the starter and choosing to use the built in thermistor instead of dropping in a second one really is a cool approach. :)

"The disconnected battery won’t charge with my trickle charger" Once you get it woken up and trickle charging I'd wonder if the system runs better without the dead weight of the drained battery. Did removing the dead one solve the issue?

Are you saying that the previous owner ran the AC unit with the existing inverter and battery bank? If so, it seems like your inverter is just fine for the task. What you need is access to more energy (more panels) and more storage (more batteries).

As others have said, inductive loads have inrush currents that exceed their runtime draw. LRA stands for "Locked Rotor Amps" and you need to allow enough power to overcome that. In the case of an AC inductive load you need an inverter with a large enough capacity to ride through the spike...

"The tank volume is 90-100 litres. The tank also has a 1000w, 240v immersion heater." Disregarding AC/DC, let's say to heat 100 liters of water one degree C, you need: Kilowatt hours = (4.2 × 100 × 1 ) ÷ 3600 = .1166kwh. If you were delivering a full 1K watts to the tank for one hour...

I've been re-reading your posts in this thread and it's clear that you've taken your batteries down to their cutout point a few times now. It's possible that one battery is dead or it's possible that you're just draining them down to 0 all the time. One quick modification to the design will...

I buy these 6 pin pre-built connectors. (One side can be 8 pins but I just ignore/snip the add on 2 pin part. Cut these in half and you've got a very handy connector all ready to go. If you put one side on a terminal block then you only need to solder and shrink wrap the 6 lines coming from...

Close. Three sets of two panels each would be better. They will top out at 99v which is well under the max of 145. And 30.7 incoming amps would be well below your 80a max. Cheers

In addition to mentioning what you're trying to do (series, parallel, etc) it would be useful to snap & share a photo of the inside of the patch panel on the back of one of your panels so we can see the configuration of any diodes already installed.

It's just a resistor, there is no positive or negative. Hook it up any direction you like. :)

From what I could gather from the video, the whole system seemed odd. They keep the massive array on the roof DC all the way to the basement where they convert it to AC to feed a rectifier 10 feet away that converts the AC back to DC to tend to the batteries. Then those batteries seemed to...

The title doesn't say that this system has an AIO but there are a lot of posts trying to make such a system work. A normal system would not have those issues. In a component-based system all you need to do is wire the generator go-signal through the courtesy output on the charge controller and...

Part 13, the Truck battery is not well labeled. Is it hopefully 24V?

KNX is still popular in certain European circles but it's making no inroads globally. BACnet is still riding high after beating LON to death and should be the default open protocol to consider. Obviously modbus is a very real option too. But you generally need a computer to tie it all...

I feel more specifically that he sold snakeoil to urbanites, then he lost his mind and started calling all of his customers worthless idiots. It seems clear that he always thought that, that's just the group he had been fleecing at the time. Now he's decided that the Off grid folks are primed...

Pa. It gets cold here, there are single digit lows here this time of year but it very, very rarely goes below 0f. The smaller system has been set up for years, the new 24v one is in a new shed and this is the first winter in it so I don't yet know how cold it might get. Ask me next year and...

Mine arrived. The boxes were each torn up during shipping and there were a few scrapes on the panels but nothing electrically wrong. These panels are pre-configured for stand alone use or for series use as they have bypass diodes built right in. As I am in a design phase and am moving...

This one: https://www.amazon.com/FEENCE-LiFePO4-Rechargeable-Trolling-off-grid/dp/B0BDD196Y5/

I use this when I'm topping off a 24v bank. It's gentle and takes a long time if you have a lot of aH to fill but it works. https://www.amazon.com/LiFePO4-Battery-Phosphate-Rechargeable-Protection/dp/B0CF62DW36

You state that the comms are likely for: Coordinating charge termination That's where I think the comms would stop the issue the OP has found with his system.

That's a good point to make. Commercial BACnet controllers and even evidently some PLC's will run off of 24vac or 24vdc. That is surely an advantage over diy options like Arduino or Raspberry Pi type setups.