Just bought 4 of these before I go any further is there any issues I need to know before buying a controller.
MPPT and if wiring in series, or series/parallel, 150 volt 80 amp or over.
I'll add to the above comment: spend the extra for a good quality MPPT controller. I first bought a less expensive unit that the manufacturer swore was as good as all of the "overpriced" brands. I ended up having to buy a GOOD controller and spent far more money than I should have, with the cost of the first one. Morningstar is a quality brand, with a wide selection of models for whatever needs you have. There are other quality brands, as well, I just happened to have good luck with Morningstar. Get batteries that have high Amp Hour ratings. If you settle for average capacity, you will find yourself looking for shore power or running your generator often. The whole solar exercise would be pointless.
If you are having professionals design and install your system, these two points are still valid. If you plan to design your own system, make very sure that you spend a LOT of time researching before you ever spend a dime on equipment.
This forum is full of folks who have gone both routes, and by using the search feature, you will find your research efforts will be a whole lot easier.
Didn't someone on this forum recently post they have an extra Morningstar MPPT 65 amp unit for sale?
We think this a a great controller, and it has an Ethernet connection for easy to programming from a computer.
With almost 1200 watts he will need a minimum of 80 amps in one controller or use several smaller ones. As said, best to buy a good quality one, I have used Morningstar, Outback, Midnite Solar and Victron with good results.
I have 3 Lifeline 8D 250 AH AGM's and don't plan on adding any more. I also want to keep using my Xantex SW 3012. I will do the install myself and so far am planning to buy the Midnight Solar Classic 150 MPPT I have book marked for the last year all the information I could find on the forum, but this is not my field of experience so a lot of searching and watching U tube videos is my next step.
When I started buying parts last year, I bought a 65 amp controller expecting it to be plug-n-play. But after buying the Suniva 285W panels, it wouldn't work. I went to the Morningstar website and used their solar calculator and found I needed the 80amp MPPT. It's worked great for the last 9 months. I initially got worried when I went over 100 ah in a day, but have no worries taking it to 180 ah. It may take 2 days to get back to "0", but batteries and controller are doing a great job.
I have a room full of pretty blue Victron products that I'm still in the process of "getting ready" to hook up. In the pile is a 85amp solar controller. I'm sure they will work fine in the mean time they sure look nice.
I won't be starting the installation until after Christmas so plenty of time to collect "pretty parts" also. But once I get my teeth into something I don't stop until finished.
Make sure you use the right wire size and circuit breakers.
Pierce has a post with sizes and part numbers along with a good description on DIY.
My Midnite Class 150 is conservatively rated for 96 amps but I think you can put at least 1500 watts of panels up top but should limit the voltage to about 10% less than the 150 volt rating. For about $500 delivered, I consider it the best on the market. It's provided trouble free service for the years we have had it installed.
I typically see a winter maximum of about 600-700 watts from our 1140 watt potential. This is with a flat installation. Summer, especially in the lower U.S. will come closer to the panel rating. Unless you are running a residential fridge, four large commercial panels should be enough to have plenty of lighting and 4K TVs plus run a latte machine and microwave in the morning without ever having to start the generator.
If you can't find my post with the sources/parts numbers/prices, please PM and I will email it.
Pierce
I have been slowly plugging away at the project. I made a battery compartment for 6- L16 AGM Lifelines. I built a battery platform that is supported by the basement floor and the ceiling above to help split or take some load off the floor. I will actually start installing "pretty stuff" Monday after I install the battery bank. I have the aluminum to mount the 4- 300watt panels and will glue them up this week also. I should achieve a fast snail like pace from now on.
Allen at Bay Marine (the BEST) told me that I would probably never see over 85 amps and if I did the controller would limit output to 85amps, so a bigger solar controller was really not needed and no damage would ever result if more than 85amps came in.
I move like a snail because I'm completely out of my element with this install. I rely on people like Allen for there advice and go with what they recommend. I move slow because I have to rely on common sense when learning as I go.
Advice from Roger Engdahl and Roger Fleming have been a huge help.
I recommend wiring in parallel, since it is a 12 volt system. The MPPT will have better efficiency converting your 31 Volt panels to 14 Volts.
That might happen, right now I am trying to figure out wire sizes for the 2 in parallel at 72 volts vs. all in parallel at 31 volts. Also I have to figure out how to get the wires off the roof. The coach came with residential refrigerator and the old vent was fiber glassed closed.
A small loss of efficiency when running higher voltages, but a lot easier to run #10 than #2 wire, Grid tie systems [selling solar power back to the electric company directly] often send 600 volts through many panels.
MPPT Charge Controllers: Page 2 of 2 | Home Power Magazine (https://www.homepower.com/articles/solar-electricity/equipment-products/mppt-charge-controllers/page/0/1)
12V 18Ah CB19-12 Sealed Lead Acid AGM Rechargeable Deep Cycle Battery FREE... (http://www.ebay.com/itm/12V-18Ah-CB19-12-Sealed-Lead-Acid-AGM-Rechargeable-Deep-Cycle-Battery-FREE-SHIP-/321802123491?hash=item4aece6b8e3:m:mEE0opf6IdaMGYHmkKtGL8A)
I use 3 of these in one of the race cars to eliminate the alternator . They test @ 22-23 AH. Would 20 of them make any sense for a Solar bank?
Price wise batteries a good deal, but you would spend a lot on wire and connectors
Lots of ways to do this.
Be sure to use a big enough controller and all of the appropriate fuses or CB. Add a big OFF switch if you want. You need appropriate fuses atbthe battery connection end as well.
I connected the panels in parallel, I didn't want a combiner box on the roof, cables mostly run under panels or along side AC units, easy to secure and they are out of the way.
With four panels you will have 8 wires. A couple of these, 3/4" hole, 3M 4000 UV and stainless steel screws and you are set.
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Running all the cables down to a place where you can fuse each panel separately and then connect the controller is much easier and more servicable that combining them on the roof.
I used a Victron MPPT controller. Flawless. There are other choices as well.
Think this through well, where will all of the parts and wires go? Having a good plan makes the doing easier. If you are not sure, ask more questions.
Super easy to just go to solar panel wiring | eBay (https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR1.TRC0.A0.H0.Xsolar+panel+wiring.TRS0&_nkw=solar+panel+wiring&_sacat=0) and order up some #10 for either one of your designs. I bought a gray plastic electrical box with two inlets for my electrical flex conduit and the third opening is larger so I just drilled the roof above my compartment I used for the controller. Use a stud finder to make sure the hole clears any aluminum frame members. The solar wires are very easy to cut to length and put the connectors on. So easy that I laughed when I did it the first time. You then connect the positive of one panel to the negative of the other one with the quick connect couplers and feed the TWO remaining wires (one from each panel) with the 72 volts through the flex conduit, push the conduit through the box on the roof after feeding the wires down. I used Adel clamps to secure the conduit to the roof under the panels. I used GE Silicone II to seal all holes through the roof. Use a label machine on the wires so you always know where each one came from.
The advantage of the series wiring is you will have less loss (not much either way) and only two wires through the roof so easier to keep neat and wire to a bus and then to the controller. I used large welding cables to essentially bring the battery to the controller. Bringing the big cables up to another bus where I made a short run to the controller connectors with smaller wires. I ran everything through two breakers for the panels and two breakers on the battery side. I also put in a fuseable link where the big cables connect to the main bus down in the compartment. I used backerboard everywhere I could to reduce any possibility of fire. Here is the link to all the photos: https://goo.gl/photos/9KGwM2Zk28f5s4NW8 Even if you only bring two wires from one conduit down, it's nice to have a electrical box on the roof with room for two for future expansion and also a removeable lid so you can feed the wires down. Our installation is slightly more complex as I chose to incorporate the breakers above the Midnite controller.
So, looking at the photos, why didn't I make a continuous run with the big cables rather than putting in a small box? My cables were not long enough plus I wanted to tap into the 12V for a couple of audio amplifiers.
Chuck, I will be at the SB Airport fire station until sometime on Sunday if you want to drive up take a look. I have the tarp off getting ready for the trip so I can take photos of any/all(s) part of the installation. Will email a diagram/schematic in a couple of hours.
You share the same love of the June Lake area that we do. Never crowded and no need ever for AC. Photos from Oct, 2011: June Lake 2011 - Google Photos (https://goo.gl/photos/rEmJ9WcWaR2y7BZE6)
Pierce
Place panels where they won't get shadows from roof top equipment. Some panels will not work if one cell is in a shadow
Wantabe
Ours still get good output even if partially shaded. Naturally, best output in full sun and especially if the sun is directly overhead. We will have almost full voltage from the panels but no amps before the sun is even up. Amazing. This is the reason the controller manufacture likes to keep the voltage 10 percent below the rated controller specs. Solar panel voltage is rated at 77 F degrees. Below that, the voltage is HIGHER and if in freezing temperatures, the voltage can be much higher than the rating. Some controllers either will not turn on until the voltage drops or in some cases, the high voltage will severely damage the controller. All things to consider when selecting the voltage you bring into the controller.
Pierce
Does anyone know for sure or will anyone take the time to contact a or their battery maker and ask if the slow charging that solar induces versus the inverter/charger or alternator method affects the batteries life?
I understand it's a necessary evil but the info ahead of time might offer alternatives like equalizing lifeline AGM's more or less often.
Gels cannot be equalized. Non lifeline AGM's cannot be equalized.
The 20% of capacity charge rate mentioned I have seen used by most, if not all, battery makers and was built in our coaches systems.
Unknown how or if it will affect the cycle life or capacity.
Any actual info around?
There was an alternate slow charge method I think on lifelines website.
Like I said a necessary evil. Maybe. Just what exactly may we be doing and is there anything to worry about long term.
The MK engineer mentioned many ten to twelve year life oem gel installations in Foretravel already and the factory's latest mods might double their life.
At $2k+ for a battery system the info may or may not be needed
Craneman, Consider the Magnum PT-100 controller. 100A 200V. If my math is right, will handle your 4 panels in series so only 2 wires to run.
PT-100 MPPT Charge Controller | Magnum Dimensions (http://www.magnum-dimensions.com/pt-100-mppt-charge-controller)
Craneman, Consider the Magnum PT-100 controller. 100A 200V. If my math is right, will handle your 4 panels in series so only 2 wires to run.
PT-100 MPPT Charge Controller | Magnum Dimensions (http://www.magnum-dimensions.com/pt-100-mppt-charge-controller)
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The new Magnum looks good, has almost the exact same specs as the Midnite Classic 150 but seems priced about $200 more at $590 vs $800. The display is very limited compared to the Midnite plus it does not seem to be internet capable. Magnum up until lately worked with Midnite on quite a few projects. Located close to each other.
MPPT Solar Charge Controllers | Easily Compare The Best Brands (https://thesolarstore.com/mppt-charge-controllers-c-40_41.html)
Midnite Classic 150
12V to 72V Nominal Battery Charging
Built-in Ground Fault and Arc Fault Protection
Internet Ready Via Ethernet
Additional Communication Via RS232 and USB
20 Megabytes of Data Logging Storage
Remote Monitoring Via Internet
Supports up to 2 displays (up to 1000 feet away)
Comes With a Battery Temperature Sensor
5 Year Manufacturer's Warranty
Made In The USA!
I like to review all the new models and have no problem moving on to something better when it comes along. Just has to provide better specs, warranty, options, and price.
Pierce
Or this one.
Victron BlueSolar 85 Amp 150 Volt MPPT Charge Controller - Model 150/85-MC4 (https://baymarinesupply.com/solar-wind/charge-controllers/victron-blue-solar-mppt-charge-controller-150v-85amps-mc4.html)
You can get the bluetooth dongle for $50. Free app on phone or tablet. Nice thing is you do not have to run wires for a remote display.
Alan, the owner, will give you good advice and a discount for being on the forum.
Lots of info to digest. I have no need to allow for expansion as the 4 panels are all that will fit without modifying something on the roof. I will wait a little longer on the controller but the Midnight looks like the best bang for the buck. I am hoping to keep as much equipment in the bays as possible. DW doesn't want her kitchen modified so I can monitor things, so looking for another location. Maybe the original line monitor area.
Pierce I will PM you and try to get up there to look at your system.
The Victron looks like a player too. Installing the controller close to the batteries or the main bus has the big advantage of short heavy cables between the controller and the house batteries. The bluetooth dongle Victron uses means quite a bit less hassle wiring. Locating the controller below would have saved me a lot of hassle. I might have installed the controller below and remote mounted the display/control panel. We don't use the storage to anywhere close to capacity so it was not a problem. That little compartment was a handy height though.
Everyone's prices see to have inched up almost $100. Perhaps it's summer.
Pierce
The Victron is about 1/2 the size of the midnite solar classic. As you can see I don't have much extra room.
The little box on the front is the dongle that connects to your phone or tablet. You can change settings and get real time and historic information from it.
They sell the Victron that I would need for just und $650. It would save time and money on the large cables as I could mount it in the battery compartment.
Victron Blue Solar MPPT 150/85-Tr 85 Amp Solar Charge Controller Regulator |... (http://www.ebay.com/itm/like/252349724510?chn=ps&dispItem=1)
I changed my post to read for the 150/85 Do you think the 150/70 is adequate?
The Victron 150/70 gave just a bit of clearance for my 3-300 watt panels. This is one of those places where almost big enough doesn't work well. The 85 will be better. You may never need the capacity but you need enough for the maximum possible event.
Point taken.
Better to have it and not need it than need it and not have it.
I ran 1200 watts for a while and even in the best conditions [ south, summer and sun directly overhead] never saw more than 960 watts coming in. That is about 80 amps. As the controller will shed any load over its limit, 70 might be okay but I would go with the 85 amp model. If you buy wire, controller, fuses etc from Alan at Bay Marine he will give you a nice discount.
With your coach [I had the same one] you can mount the controller in the battery compartment and only need less than 2 ft of heavy cable from controller to batteries. Running the twin lead 10 gauge into the compartment is pretty easy.
When you say twin lead 10 gauge were you running them all in series?
With my current setup, I am running in series, but my VOC is only 120 volts. With 4 panels, your VOC would be 160 volts, a little too high. I would run series/parallel which will give you 80 volts at a max of 15 amps. You would have to join the two strings on the roof but could run 10 gauge down to the controller. Bay Marine website has a wire size calculator that tells you what size wire to use at a certain voltage and amperage.
Bos'ns' Corner - Wire Size Calculator (https://baymarinesupply.com/bosns_corner_wire_sizes)
Check out these DIY videos from AMSolar in Eugene, OR. Diagrams and Videos (http://amsolar.com/rv-solar/support/) Excellent reputation and they will ship product. This week I bought this combiner box Rv Combiner Box - Roof Mount Combiner Box. Solar Panel Combiner Box (http://amsolar.com/rv-solar-panel-kit/combiner-boxes) and a few of their accessories RV Solar Panel Mounts - Mounting Solar Panels on RV - RV Solar Panel... (http://amsolar.com/rv-solar-panel-kit/mounting-accessories). I also bought all of the wire, I especially liked their round 10-2 wire ( Roof Wire - AMS Custom 10ga Duplex) for the roof wiring of the panels Power Inverter Cable - RV Battery Connection - Solar Power Connection to grid (http://amsolar.com/rv-solar-panel-kit/cables-connections) This round 10-2 wire in a round jacket worked terrific with their round weather proof connectors to the roof vent and combiner. I cannot recommend with enough enthusiasm. I may pay a little more for their products, I do so because I know they have quality products and they are always there for me when I need info and accurate explanations.
Finished! I am so glad I saw this lengthy video from AM Solar, and watched prior to installing my system. I ended up abandoning my purchased combiner box and Renogy 10 gage connecting cable. I substituted AM Solar's Roof C Box and their round 10/2 cable from panels to C box, and their small 3M type cable to roof tabs. I am more than pleased with their Roof C Box. It made installation easier, water tight, and now easily expandable. (Although I doubt I will; my previous solar was MPT 150 watt for 10 years and it met 90% of my needs, now with 2 @ 280 watt panels, MPPT controler, I believe I am set). Easy access for large wire size to controller, water tight, room for expansion, genuine quality, comes with easy to install glue down 3M tape.
Roof C-Box (http://amsolar.com/rv-combiner-box/20-roof)
are those 140 watts each? look to small to be 280 watts each
Yes, 65 inches by 40 inches. The pictures are of LG280S1C-G4 280 W each, the LG ones Wholesale Solar sells now are 300 W, approx the same size 66 X40. This is the spec sheet for the two I have. LG280S1C-G4 | LG Mono X® Plus Module | Forward Energy | GridReady | Products... (http://www.lg.com/us/business/solar-panel/all-products/lg-LG280S1C-G4) and Wholesale Solar specials Solar Panel Sales - Solar Power Systems for Sale (https://www.wholesalesolar.com/specials) I bought them there because they seemed to be of good quality and I could drive to pick them up and back in one day as they are out of Lake Shasta, CA. right on the CA/Oregon border off Hwy 5.
Typical 280-300 watt 72 cell commercial panels are usually 65 to 76 inches by 39 inches and about 2" thick. With that length and assuming a 1 1/2" roof clearance, three mounts down each side should be used.
Pierce
I used 12" long mounts (made by my metal guy) bent at the correct angle for the roof curve. One at each corner, lots of VHB tape surface. About $10 per corner. Well bonded VHB tape has a 91 psi tensile strength.
I have 4 connection points on each of the panels on my roof.. I tested them for 2k miles at speeds of 80 mph + headwind and they are holding well. Unbelievable actually .. Made a VHB believer out of me and I am not easy just ask my wife
I recommend about 4 inches of roof clearance. This provides better cooling and makes it possible to clean under the panels.
Continuing with the project I have 2 choices for mounting the controller. The battery compartment or next to my inverter in one of the storage bays. The cables attached to the inverter are large enough to carry the load to the batteries. Is there any difference hooking up at the inverter cables or at the batteries themselves? The inverter location would make it easier to put the monitor cables up to where the factory voltage monitors are in the coach.
I am still reading many posts on the issue of a combiner or direct link to the controller. It almost seems to be a ford vs. chevy issue and I am trying to weigh the pros and cons of each.
No difference if the inverter supply cables are any size at all.
I did my series/parallel connection about a foot down inside the roof. I could have done it on the roof top or further down inside. Doing it sooner means slightly less loss because of the higher voltage but in the real world, doubt if it makes much difference.
Pierce