Solar Install - Did I do something wrong?

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Small Cabin Forum / Off-Grid Living / Solar Install - Did I do something wrong?


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MarkG Member	# Posted: 23 Jul 2014 10:23am Reply Ok, I purchased an AIMS 4kw solar kit. It included a 24v 4000 watt inverter, (8) 230 watt panels, (8) Vision 6 volt 225ah AGM batteries and 2 AIMS MPPT 40 amp charge controllers. They will be setup as master/slave once I get the correct cable, but for now they work in parallel (if that matters) Panels wired in series (2 sets of 4) and each set going to a controller Batteries wired series parallel (24 volt bank of 8) for 500ah. My problem is I have a mysterious power drain/loss somewhere. So last night I took the following readings using a volt meter. Time Read Volts Read 10:30 pm 25.6 Volts (100% charge) 11:45 pm 24.29 (95% charge) 12:30 am 25.20 (90%) 1:00 am 25.16 (85%) 8:00 am 24.58 (65%) How am I losing 35% in one night? What is running between these hours? 7 cu ft chest freezer converted to fridge. (my watt meter over 24 hours shows .15 kw used (150 watts). A few 12 watt LED lights when reading before bed Inverter running (running watts is 52.5) Did i wire something wrong maybe?

MtnDon Member	# Posted: 23 Jul 2014 03:30pm Reply Quoting: MarkG What is running between these hours? I would start the troubleshooting by first disconnecting all loads and bringing the batteries to full charge. Then let the system stand idle overnight to be sure the batteries are able to hold the charge that long. No loads at all on the batteries but leave the charge controllers connected to see if they are back draining. If that leaves the batteries still with a full charge 8 - 10 hours later I would slowly begin adding loads. Start with just connecting the inverter and leave it switched off, no loads of any other type either. Check the batteries 8 - 10 hours later. If all is still well, then turn on the inverter, but again no loads of any kind on the inverter as well as no other DC loads on the batteries. Let sit again for the test period. If that passes then connect the fridge. And so on. One and only one change to the system at a time. If you had access to a good clamp on type of AC/DC current meter that would cut the test time down to a few hours at most. With the batteries losing charge so rapidly, IMO, there is either a bad cell/battery or a large phantom load.

creeky Member	# Posted: 23 Jul 2014 04:40pm Reply It's odd. If your inverter is running 52.5 watts that's 525 watts from 10 p.m. to 8 a.m. That's a good sized load. And when your fridge kicks on it will push the battery reading down. So if you took your measurement just as the fridge kicked on you are not measuring the actual state of charge. The same goes if you're going by the stored reading on your solar controller. If the compressor on the fridge pushes the voltage down it will record the lowest voltage, whether that is the actual state of charge or not. How much power did it take to recharge the system? That'll give you a better idea of how much power the system used overnight. Nice looking system btw.

MarkG Member	# Posted: 23 Jul 2014 07:35pm Reply I appreciate your replies. This gives me something to work on. Don't go anywhere! I'll likely have more questions as I'm figuring this out.

creeky Member	# Posted: 24 Jul 2014 08:18am Reply MarkG. Don't worry. I'm 40% ; sure it's the "blinking lights" syndrome. And everybody with a new solar system goes through it. I see 12.23 or 12.24 in the morning on my system. Is that the true state of charge. No. A solar input of 30 or 40 watts is enough to push me up to 12.9 or 13.1. And I am in absorb by 10 a.m. on a sunny summer day. This would indicate I'm using about 1 kw overnight. What you're seeing appears to be normal. *blinking lights syndrome: Hey, a yellow light on my solar charger is blinking slowly. Something must be wrong. Checks manual. Oh. Blinking yellow light indicates charging. Okay. There are many variations on this theme.

MarkG Member	# Posted: 24 Jul 2014 04:23pm Reply LOL Thanks creek. I am following MtnDon's suggestion to be sure (my sanity?). So far everything looks good. Batteries held full charge overnight (no loads) so I know they are good. Tonight I will be running just inverter, again no loads. Try the fridge overnight after that. Thanks again, and I hope to get used to these lights! They're always blinking! -Mark

ILFE Member	# Posted: 26 Jul 2014 01:29pm Reply Yep. Check one load at a time. Eventually, you WILL find the culprit. I for one, anxiously await your results!

Hunterda98 Member	# Posted: 26 Jul 2014 01:53pm Reply Hi Markg, Was it difficult to install the system? I'm assuming you did it yourself. I see lots of online kits for about 10,000$ for about 2.5 kW systems. But my local installer wants to charge about $17,000. Any thoughts?

MarkG Member	# Posted: 26 Jul 2014 09:26pm - Edited by: MarkG Reply Well, before I could do the next test (checking just the inverter/no load), we went to TN for the weekend. As for the system, it came to 6500.00 with shipping. I had NO previous solar experience other than reading Solar for Dummies, and some internet research. I borrowed a volt meter from my father-in-law and got started. It took about 3 days to install, but I spent a LOT of time double checking stuff BEFORE, DURING, and AFTER each part was completed (there were NO instructions, just the components). Youtube is your friend... If I was to do it again I could do it in a day easy. For the money I feel it was a good deal. I was looking at Outback and others but for the same money all I would get was a 2kw system. I researched AIMS and they're no Outback but the reviews were overall positive. So, twice the kw I was sold. Also, I wanted some built in redundancy (panels in 2 series strings, 2 charge controllers, and I have a spare 2kw inverter for a backup as well). Other than batteries I can lose one controller, and or panel, or the inverter and still be able to limp along on 2kw. The only thing I'm not pleased with is the power consumption of the inverter. It does have a "power save" mode but I cannot use it with having a fridge. That being said...I've pretty much decided I'm going to get another small inverter/panel/controller and segment off the fridge to its own little system so I can shut the 4kw inverter off through the night. As for the setup, it was not that bad. Just understand that SOME things may not be included in a system and are needed. Wires the correct length (where are you going to put the batteries), does the system require a SHUNT (which is almost never included), misc wire for sensors, fuses. DC load panel and shut-offs. I probably spent another $175 on items that where not supplied which only delayed progress. It still early in the game but overall I realy like the product. Tech support sucked but thats what you guys are for! lol....

MarkG Member	# Posted: 26 Jul 2014 09:45pm - Edited by: MarkG Reply btw, this is what I ordered. Ignore the picture (they use the same stock photo for every system). Click "features" for the list of items included. http://www.theinverterstore.com/4000-watt-pure-sine-24-volt-80a-off-grid-solar-kit.ht ml

ILFE Member	# Posted: 26 Jul 2014 11:39pm - Edited by: ILFE Reply Quoting: Hunterda98 Was it difficult to install the system? I'm assuming you did it yourself. I see lots of online kits for about 10,000$ for about 2.5 kW systems. But my local installer wants to charge about $17,000. Any thoughts? A few points here: 1. Installers have to eat too, mate. They certainly are not in the business of doing it for charity. 2. Did you compare the hardware your installer would provide, as apposed to what you may buy in a "kit"? Personally, I would never buy a complete kit and install it. Nothing against the original poster here, or anyone else who went with kits purchased online. But, the kits I have seen offered, usually do not include all quality hardware, even if they have quality panels. (Now, if you can pick and choose the parts in your kit, now we may get some where.) Usually, the kits will include some off-the-wall, substandard Chinese made controller and inverter. Trust me, I have gone both routes regarding inverters and will never make that mistake again. I purposely bought two Chinese controllers to test against my MorningStar controllers - PWM vs. PWM. Guess which ones won, hands down? I had a 1,500 watts "Chinese made" inverter that - well, should have never left the factory floor. I certainly should have never picked it up at the local DHL office here. 3. Installers, if they are worth their salt anyway, will have things come to them second nature, that may never cross the mind of a newbie. It is only because the newbie is ignorant of the things they deal with on a daily basis. (Take a look at some YouTube solar "home" install videos, sometime. You will see what I mean.) Some of those people, simply put, should not be on a roof, and certainly not working with any sort of voltage! My suggestion is, find the best deal you can on solar panels and buy them. Look at a reputable store, like Northern Arizona Wind & Sun, for your controller, inverter and other installation parts. For the record, I live half way around the world. Before I will buy anything else locally again, regarding controllers and inverters, I will pay to have them shipped from the states, especially if I can get an American made product. I have seen what the "other guy" makes, and it ain't pretty. Buy your batteries locally. (Yes, how much, exactly, are you paying for those batteries and to have them shipped to you?) You can visit your local auto parts store, Wal*Mart, etc., and get some decent quality golf cart batteries that will last as long as any included in those kits online. So, before you go making any harsh decisions here, guys, please make sure you do your research first, and make appropriate comparisons. Don't just go with a kit because of the bottom line cost being x number of dollars cheaper. Trust me, they are shipping you something that is cheaper, too!

MarkG Member	# Posted: 27 Jul 2014 09:43am - Edited by: MarkG Reply All good points ILFE. I for example spent months looking at my options with the money I had to spend. I researched each piece of any kit individually. Panels, controllers, inverter, and batteries, to include the company/manufacturer (everything in my "kit" was from the same company/manufacture so no hodgepodge). How long have they been in business? What are the warranty and return policy? I looked to Amazon and Google to see the cost and reviews of each piece as well as downloading the manuals to evaluate all the functions based on my needs (here are my charge controllers for example). http://www.amazon.com/AIMS-Solar-Power-Charge-Controller/dp/B007L6E68S/ref=sr_1_1?ie= UTF8&qid=1406466808&sr=8-1&keywords=aims+mppt+charge+controller Manual - http://www.aimscorp.net/documents/SCC40MPPT.pdf If you are comfortable with doing the work yourself and willing to do the research before hand you can find good deals in such a competitive market...just know what and who you are getting for your money. As for the batteries? I got "free shipping" on the batteries. No, they did not inflate the price either, as they were still $80.00 per battery cheaper than buying the same ones off Amazon, and they are offering free shipping too. http://www.amazon.com/Volt-Cycle-Solar-Power-Battery/dp/B00J5RMG24/ref=sr_1_1?ie=UTF8 &qid=1406471292&sr=8-1&keywords=vision+3fm225+agm+battery Trust me, unless you live next to the plant you are paying for "shipping" regardless of where you buy... -Mark

creeky Member	# Posted: 27 Jul 2014 11:45am - Edited by: creeky Reply Mark I thought MtnDon's instructions were clear enough I didn't need to add to them. I just wanted to say that after a few years on the web and watching "newbies" launch systems you tend to see the "blinking lights" syndrome, um, a lot (as in "been there"). What's more likely. Blinking lights syndrome (common) or bad battery (rare)? And it's nice to see someone sharing a "kit" experience. I've seen mostly "diy" here. Btw. have you found your phantom load now that you're able to rule out a bad battery? Or is this just the natural state of things with your lead acid battery pack (ie. low voltage readings caused by a temporary high load). I suppose one advantage of the diy approach is you get to cherry pick. The best from everyone. But a kit will have the advantage of being tried and tested. (ILFE, europe has some amazing new inverter/chargers if you're still looking. TBS is a name to look for(edit: maybe Samlex in Europe?). Tho I would quibble about some of the features (too big an inverter, too small a battery pack)... your kit was a really good price... I think the best I've seen. Does your 6.5k include tax. So can we call it 7 k. That would be less than $2/w installed. wow. And building in redundancy. excellent. So, as Hunter points out, is your 3 days and some fiddling worth 7k? I would think so.

ILFE Member	# Posted: 27 Jul 2014 03:25pm Reply MarkG, thanks for the reply, sir. creeky, thanks for the lead. The farm is 100% off-grid, though. (I may have neglected to mention that in my previous reply?) An inverter / charger would not be very suitable for my situation.

creeky Member	# Posted: 27 Jul 2014 04:18pm Reply not to go off topic: but: ILFE. tbs has a bunch of inverters. i thought you might like a supplementary charger for your rainy season as an inverter / charger is ideal for off grid. to clarify: an inverter/charger is one that inverts dc power from batteries to supply ac power. the /charger portion is used when a larger than inverter supplied power load is required or when the batteries are low and need recharging and no solar is available (your rainy season?). the /charger is built in with an "ats" or automatic transfer switch. which means if you connect a generator it will simultaneously charge your batteries and supply power to your loads. note that my farm is 100% off grid as well. for 5 years now. 1 year no power other than a genny. 4 years on solar. I use a genny powered battery charger for my 2-3 month cloudy season. I run it up to 2 hrs a day. 1 hr morning and 1 evening. cost me around 50 bucks last year for gas. so pretty reasonable. two winters ago I saw a day with 0 watts solar - and that's with 1kw of panels in good working order... so pretty cloudy indeed.

MarkG Member	# Posted: 27 Jul 2014 04:31pm Reply I'm still in TN at the moment creeky. Will continue my "test" when I head back on Monday. I think I found part of my problem. I did not have the charge controllers negative wires going through the shunt (only the voltage sensors were) so I was not getting a correct SOC. I relocated the cables correctly and it reset the controllers. Reprogrammed the controllers and got a full (correct) charge reading. Then I had to leave for TN. I think between the inverter draw (and possible fridge compressor) on the battery at the time I was using a volt meter to check charge state I was getting bad numbers (as you stated in your post). As for the system: No sales tax. Came to 6500.00 and change. It also qualifies for the 30% federal tax credit too. I agree on the inverter size to storage. My current usage (pun intended) is well below the inverter size...but it's room to grow I guess. I wanted to learn how to install my own solar and though frustrating at times it was a lot of fun. So, a "kit" kinda made sense as I know all the peaces were meant to go together I just had to figure out the puzzle was put together.

creeky Member	# Posted: 27 Jul 2014 04:50pm Reply what a deal. makes me so happy to see prices continuing to drop. nice. you're going to have that system for many decades (and I certainly wish we got a tax credit in the great white polite north). congratulations.

ILFE Member	# Posted: 27 Jul 2014 07:14pm - Edited by: ILFE Reply Quoting: creeky ILFE. tbs has a bunch of inverters. i thought you might like a supplementary charger for your rainy season as an inverter / charger is ideal for off grid. I'm sorry. What I mean is, we use solar exclusively. We have no mains, no generator, no hydro generation, no wind turbines. Solar is the only way we generate power. If the batteries get too weak, then we are simply SOL until the sun begins to shine again. On a more positive note, I am currently using / testing a Midnite Kid controller. I have learned, from the Midnite Staff, that you can seriously over PV the unit with no worries. No matter how much PV you add to it, it will only allow 30 amperes to the batteries. So, my test plan is to add so much PV that, even during overcast days, enough energy will still be harvested to charge the batteries. If this works out like I hope it will, I am going to purchase another Kid for the array at the farm and transfer my current controller (MS ProStar 30m) to another array solely to charge batteries for the neighbors.

MarkG Member	# Posted: 27 Jul 2014 07:21pm Reply Quoting: ILFE you can seriously over PV the unit with no worries. No matter how much PV you add to it, it will only allow 30 amperes to the batteries. Now that's cool.

ILFE Member	# Posted: 27 Jul 2014 07:23pm Reply Quoting: MarkG Now that's cool. Yeah, it is too cool. I learn more about what it can do, every day.

creeky Member	# Posted: 28 Jul 2014 11:09am Reply Hey ilfe. I went the over panel route since day one. Morningstar controllers also reliably handle over amps. And, with 60 amps charging while I should max out at 750 watts I've seen a record of 932 watts one very cold winter day. Course it is there for cloudy days. I was also quite pleased to find that the second panel set hugely decreased my genny time. You will like. That kid looks pretty good. If you're putting up that much panel, tho, why not go more amps on the controller too? Get even more of the power into your batteries.

ILFE Member	# Posted: 28 Jul 2014 12:19pm Reply creeky I know nothing of MorningStar's MPPT controllers. My experience with them is limited to PWM controllers, so far. The MS controllers I have are, for the most part, preset and automatic in what they do. Well, aside from a few settings prior to connecting them, they are. The Midnite Kid has an interactive display, up to and including setting the maximum amperes allowed for the load and battery, allowing up to 30 amps. I like the look, the style and the functions available with the Kid. It has an option of working in parallel with other units in "Follow Me" mod, or bully / wimpy mode, where two of them work together as one unit. I think, up to 12 units can work together in "Follow Me" mode. The main reason I have for over loading the controller with PV was to see how well it performed on cloudy / overcast days. I doubt I would keep more panels attached to the controller than it reasonably needs, especially during the long dry season. Here, that's when we have ample sunny days, where even an under PV'ed bank could stay full charged.

spencerin Member	# Posted: 28 Jul 2014 10:13pm - Edited by: spencerin Reply Quoting MarkG, "It also qualifies for the 30% federal tax credit too." I have a 120 sq. ft. cabin and a small solar system that cost $900. You bet your you-know-what I claimed that tax credit!

MarkG Member	# Posted: 29 Jul 2014 08:09am - Edited by: MarkG Reply From the Department of Energy's web site: Solar-electric property There is no maximum credit for systems placed in service after 2008. Systems must be placed in service on or after January 1, 2006, and on or before December 31, 2016. The home served by the system does not have to be the taxpayer's principal residence. Though my wife and I live in our off-grid cabin full time that last one is a great benefit for others with weekend cabins.

creeky Member	# Posted: 29 Jul 2014 11:01am Reply Ilfe. I like the sounds of the kid. My experience is all morningstar. Love my mppt 60s. The kid has lots of nice features I see. Follow me, and load diversion are two that catch my eye. Very useful. The ms 60 has built in Web server ... really addictive watching charge levels climb and fall. Does the kid have Web monitoring? Another advantage of over paneling is when the batteries are charging/ed and you're running a higher drain device. Mark will like 4 kw come laundry day for sure.

ILFE Member	# Posted: 5 Aug 2014 04:50am - Edited by: ILFE Reply Quoting: creeky Does the kid have Web monitoring? creeky, First, I apologize for such a late reply. Not sure why I am not receiving notifications of new replies to this thread. Anyway, no. The Midnite Kid does not currently have web monitoring. It does have LAN cable connections, and a mini-a cable input to upgrade the firmware. I keep all the specs and information that I collect on the Kid controller, in this folder: Midnite Kid (on Dropbox)