Thank you for commenting. Thank you for your info and I would love to see pictures of your system, building and mounting system….Jody. Dale. Thank you for the information on your site. Get smart with the Thesis WordPress Theme from DIYthemes. Dale. Any and all advice is welcome and I won’t be upset if you think I’m off base and have a better suggestion. Some smaller lawn equipment and motorcycles use 6-volt batteries. You are definitely on the right track. I NEVER recommend my customers build a system with one string of batteries. My roof got the same treatment, they indexed my home in total as average of +R29 radiant loss ratio when they did the siding install. Although I have not seen a 60 volt battery bank, it is likely to become common in the future for the same reasons 48 volts is so popular now. Email photos to jody@solarhomestead.com if you get a chance. Using Your Generator to Charge Your Batteries, The Evolution of the Solar Charge Controller. We use a marine style over amp disconnect which is unheard of in the RE world. The peak charging voltage for Gel batteries is 2.3 to 2.36 volts per cell, and for a 24 volt charger this works out to 27.6 to 28.3 volts, which is lower than a wet or AGM type battery needs for a full charge. I’m considering lithium iron phosphate LifeP04 3.25v 300amps. While the battery is not being charged and not powering anything, you can use your voltmeter and get a reading. Hi Jody. When different batteries are mixed the whole battery bank will operate as well as the least AH battery in the bunch or the most worn out battery of the bunch. (Remember that VOLTS X AMPS = WATTS) or (WATTS/VOLTS = AMPS). I have seen 48-12 converters with efficiency ratings of 45-85% depending on the model. If you have any questions or something to add on this topic please comment below or contact us. A large DC breaker for the solar industry is 250 amps. LIE, Welding cable is ONLY Fine stranded for flexibility, not superior ampacity. Appreciate your meaning. Magnum does make an MS2812 that will also work nicely but unless you watch your loads carefully you will need a larger breaker, fuse and cables. At 12 volts the Flexmax 60 (FM60 | $400-$600) can only handle up to 750 watts, 24 volts – 1500 watts and at 48 volts -3000 watts of solar modules. Our batteries are 12V and we have the MS2812 inverter you mention from Magnum (an excellent piece of equipment in spite of what follows). Also, will a 12 volt 4000 watt inverter work or do I need to get a 48 volt inverter? They are also high frequency to be cheap making them unreliable. a Arrow 10×12 building is about $400 at a Lowes or Home depot. 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Please help me get this configuration better and stronger because the summer heat is about to hit and I want a refrigerator and an air conditioner at the same time which at the current moment seems almost impossible! Any variations are ‘buffeted’ by the batteries. If you run the charge from the controller through one end of each bank, doesn’t that give you uneven charging of the batteries further away (even assuming you charge the two banks separately)? Divide 2800 watts by 12 volts and the surge amperage is 233. Keep it up. A typical FLA 6 volt battery will have a resting voltage of 6.25 volts while 6 volts of lithium will rest at about 6.5 volts. I have broken all the rules to cost. 12, 24, or 48. And last you really should connect the positive inverter cable to one end of the battery bank and the negative at the other end of the battery bank. volt meter (a separate instrument) continued to indicate the same voltage coming in from the modules. Double the inverters as in our system and the maximum current will be 250 amps which can easily be handled by 4/0 cable going to the DC breaker panel with a 250 or 300 amp Class T fuse, followed by two sets of 2/0 cable (one set per inverter) and 175 amp DC circuit breakers for each inverter. Or you could source 2 24VDC nominal voltage modules instead of using 4 12VDC nominal voltage modules. But there are some of course. I don’t think you can get away without it. Now my current setup or beginner set-up as I call it is two 250 watt solar panels run to a charge controller that is 20 amp and the cheaper model. The never ending mis information about “wire size savings” and you must use fine stranded welding cable has permeated the solar world like a poison. Your battery 33,600 watt hours. Wouldn’t it just max out at 60a and not let anymore power through or would it smoke Thanks. The only difference is you have not connected the battery banks unless you have them all wired in parallel. The MS2012 has a peak output of 2800 watts for 5 minutes. How many days of storage (no wind,no sun) would you need? If I knew what you meant by tiny current I could give you better advice. Good for you trying something out like this. Some 50 amp. I want to buy 3 12 volt 12 amp batteries for a total of 6 in all, hook them up parallel to keep my 36 volt current. Deciding whether to design and build  a 12, 24 or 48 volt battery bank is one of the bigger (and first) decisions you will make when deciding to live off the grid. As a general rule you would use a 175 amp DC breaker ($90-$200) as a DC disconnect for this inverter with a 200 amp class T fuse ($60-$90) and 2/0 inverter cables ($40-$100 each) which contain 1/4 the copper that 4/0 cables are made of. Almost everyone who is new to solar, wind or micro-hydro assumes that 12 volts is the way to go. What are the best choices for your first battery bank? There are multiple output chargers and straight 48 volt units throughout a wide-range of amperage outputs. Then the unused positive from one module and the unused negative will be 24 volt. Like I said previously fine stranded wire is used mainly for its flexibility and a little because their is more copper in fine stranded wire than large stranded wire. You sound pretty handy. For your readers, please suggest they put up a “POWER HOUSE” like a metal building and that they do not install directly onto their home. Your battery and solar module configuration will work great. Just pair the solar panels in groups of two. They look like old mouse traps. Hence the inefficiency. I still would like some clarification on a few concepts if you’re able to help. Wow. Correct me if I’m wrong. You could always put a BLUE SEAS DC disconnect switch between them on the positive side that would give you the option of using bank 1, bank 2, both or none. I agree…I am 100% against 48-12 and 24-12 volt DC-DC converters. Okay I have a ”Tiny” house 12 by 20 ft. Kobalt 24-volt max 1/2-in cordless drill/driver comes with a 24-volt max 2.0Ah Li-ion battery, charger, belt clip, double-ended driver bit, bit holder, auxiliary handle and soft bagBrushless, highly-efficient motor delivers 650-in-lbs of torque and provides long-lasting life and run time2-speed gearbox allows for drilling and driving at 2 variable-speed ranges (0-550 and 0-2,000-RPM) Hope you are having a good week…Jody. Please ask if you have anymore questions or I was unclear with this one. Even at lower power consumption levels (like 1500W — water or space heater), if the bank is lower than about 70% SOC the voltage is depressed too far and the inverter cuts out (user-defined @ 11.0V to protect the batteries). �X�I��\ Thanks for your help. Advantage or disadvantage? You could likely sell your MS2812 and upgrade to a MS4024 or MS4048 for not that much more money. One question I have; Am I able to pull 12 volts off a 48 volt battery bank for simple things like led lighting or an exaust fan for my ekolet composting toilet?? Most states have no DC loop code restrictions. And a semi cheap 11 – 15 volt 1000 to 2000 watt power inverter with a super long extension cord plugged into that. I would love to answer your questions right now however I an in Zimbabwe training solar installers (http://globalsolar.co.zw/) until Saturday. I plan on going off grid before the elections…………………Thank you in advance to anyone that will answer these questions or suggest other things to consider…………..i’m all ears. The same goes for travel trailers. So while we “can” pull up to 2800W at a time, that is 367A…about a “C/3” load. The cable would have to be 9.5/0 (750KCM) and over .999″ in diameter if using stranded wire. Sorry you are having the troubles. 3 inverters /chargers Selectronic sp-pro spmc241-au. Hi all; This is a huge amount of current. The maximium DC input to the inverter is 68 volts and the inverter’s continuous output is 4400 VA. Not quite sure how to do that or whether I should do a single bank of 48 volts/370 amps? Sorry I’ve been tardy in reply but we’ve been away for a couple of weeks. Try to bend a 4/0 solid or even large stranded wire. I am planning to renew my solar system which is off grid 3 phase. I would like someone that is not out to sell me something answer this question. I have broken the rules myself to get the job done. You will know if it is low frequency if it is heavy and not super light. Just not installed yet For one thing, Welding cable is the ONLY way to go. We heat a 2048 sq foot house with a wood stove as needed and 90% of the winter just a Empire through the wall 35,000 BTU propane heater. However as you have decided on 48 volts, you will need a 48 volt inverter. If you know anyone who wants one I’ll sell them for 9 K each and a $500 contribution to Solarhomestead.com] Most important factor is NEVER put this material in your home, on your home or next to your home. No. We now have 3 strings of 8 x Trojan L16s. Jeffery at Global Solar would be excellent to help you and is very close to you. I purchased a Windy Nation package of a single 100 watt module and controller, with the controller being a little more sophisticated than the the first but still 30 amp and hooked it up to my two existing modules (not the Windy Nation module yet) and it, too, worked well for about a week. The MS2012 is a low frequency (big, rugged and heavy) pure sine wave inverter with a massive power factor corrected (PFC) battery charger that works well with fuel powered generators. I agree with you about the US as well as the rest of the world seeing as all the world’s currencies are fiat and backed by the US dollar which is backed by nothing. Or you could use one or two Magnum Energy 120/240 inverters. You could have a disconnect switch between them if you HAD to shut one bank down due to a defective battery. Maybe you could make a timed circuit that would do this automatically from you. But, the main reason our system works so well is that we have NO large amp appliances. I am from South Africa and want to start my own of the grid system. With this info I could give you an idea of the size of battery bank you might need. If I have a battery failure I have to remove the remove the bad battery and cut my storage to 2/3rds until I can get another battery but I am still operational. They are getting older so I’m thinking of setting up another bank and dedicating one charge controller to the new batteries. In the process of developing some experience, I bought a cheap 30 amp controller and installed it to my two, in series, modules that I constructed with cells from Amazon. You are going to need at least two more solar modules with an MPPT controller. I ordered my cabling, 6awg wire for multi panel groups, and 3/0 for inverters from Wireandcable.com for under half the cost of that “solar required wire” and made my interconnects 6v(12vdc) with typle k 3/4″ copper pipe which is capable of over 900 amps and did it for $1.20 a battery. The Mean Well inverters are absolutely dollar for dollar the best I have tried. Our main solar/wind power plant is in the shop near the house. You are so correct about 12 volts versus 24 volt systems. Many will catch fire or have a Mosfet failure in the case of high input volts from a controller. I am going to have a thousand gallon propane tank buried on the property to run the stove and refrigerator. If money is tighter go with 24 volt models (8 batteries in two strings) preferably using two strings so if a battery goes bad you will still be able to limp on half your battery bank until you get a replacement battery. Fine stranded has less air space between strands (allowing more current) than large stranded plus large stranded is almost impossible to route (bend) large stranded wire like 1/0, 2/0, 3/0 or 4/0. No other controller is made to go between a turbine and battery bank unless it is built for the specific turbine like a Bergey or Jacobs. 3 inverters ABB PVI-4,2-TL-OUTD Let’s say you went with a 2000-2500 watt inverter…you would need 2/0 (00) cable connecting your batteries and your inverter. Do I have a problem with them? As an aside, I read with interest your struggles and successes over the years, both professional and personal and I hope your endeavors continue to peak your interests, challenge your skills, bring happiness to you and your family and provide you with the feelings of accomplishment that we all seek! Please I will appreciate your support in sharing your knowledge in what is important and information. You cannot mix 7 amp hour (AH) batteries with 12 amp hour batteries. Reliability and efficiency and have been the main issues. That amount of cable is very expensive. I am in the very beginning stages of this and would really appreciate some knowledgeable folks helping me to save time and money by doing it the way I want it the first time. It is a 60 amp MPPT (maximum power point tracking) charge controller and the 60 amp rating refers to the battery voltage. After burning up a few $2500 inverters in under 1 year I swapped to Mean Well and have no losses anymore. High frequency inverters on the other hand are light, cheap and don’t have the surge capacity or reliability. Using 48 V batteries is usually a good idea in an off grid system. Outback is very pretty. They can each surge at 6000 watts. A 12 volt 4000 watt inverter is not feasible anyway as the amperage would be far too high. Another reason 12V battery banks are a poor choice for any “serious” sized system is the voltage depression that comes with large loads. I have three such banks. 300W panels 40pcs. I am sure this is too late. Use a DC 250 amp circuit breaker for your disconnect and a 300 amp class T fuse with holder for your catastrophe fuse. Thank you for leaving a comment and questions. I have an off the grid cabin. It also has the effect of making the batteries last longer due to Peukart’s law. If we compare your solar array of 11,400 watts and your battery storage of 57,600 watt hours, the battery bank is too small. Ty. Check these guys out…. 400 watts of solar produces the same amount no matter the voltage. If my fellow off gridder only needs a 2000 watt or smaller inverter, than 12 volts might be the way to go. And thats in the process now of being done. I really want this to work first time without going broke. We have both a 250 watt and 1100 watt 48VDC Exeltech inverters here as spares in case of catastrophic damage to our main Outback Power System. 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Any one doing it this way days do you want to be (!