Morningstar MPPT solar controller , and showing amps from panels.

[capnrob97]

Looks good! I just got this controller today. Looking forward to trying it out.

[wiboater4]

I don't think the wire size is a problem. I'm not running very far. I've been off work for quite awhile now otherwise i'd have a way of testing the watts. Might still invest in a meter for that. I'm still waiting for a good sun day to test the panels seperatly . Might try hooking the 2 large ones up in series for 24 volts.

[helloman1976]

@wiboater4 I would for sure run in 24VDC if possible. I'm not a fan of 12V unless you are running very short wires and even then just use 24V. I use 8ga building wire I got cheap from HomeDepot and at 30 feet I read .9 ohms and at 50 feet I read 1 ohm. I'm running 2 x 24VDC 175W panels in parallel and making very good numbers, about 1.6-1.8kwh per day and that's with them laying on top of my hot tub not even mounted yet. I'll be posting videos soon! Thanks for your post!

[wiboater4]

@helloman1976 I just switched the 2 72 cell solar panels over from 12 volts to 24 volts. really made a difference. from one panel I was getting about 11 amps and that wasn't in real good sunlight. I still had to order another Mppt charge controller. The morningstar was supposed to be good for 44 watts at 24 volts but when i hooked up the 2nd 24 volt panel it only added a couple more amps.

[wiboater4]

@wiboater4 That's supposed to be 400 watts not 44. I ordered a Bz 500 watt mppt controller. both panels put out over 10Amps seperately hooked up but when both are connected to the morningstar it only reads 12 amps. at( 35 volts panel side of controller) hooked up to the 12 volt battery bank thru the controller

[helloman1976]

@wiboater4 Awesome! I'm glad I could help someone out. My system is going well also. I just ran 60 feet of 8 gauge stranded copper wire through my attic, total resistance 1 ohm lol. I'm getting about 28 to 30VDC out my 24VDC panels under load which is pretty good. With charge controllers you always want to buy the biggest and baddest one you can afford and MPPT is an absolute must have. Let me know if you need anything at all, check out my videos!

[wiboater4]

I tested the panels and got 20 volts from the small one and 20 volts each from the 2 doubles in parallel, didn't check each seperatly on large ones. With just the small 36 cell panel hooked up I got 2.5 amps out of it, but not the best sun during test. at that I should be getting 12.5 amps total from all the panels but I'm not..

[Schweizer135]

@wiboater4 Perhaps your wire gauge it too light for 30A over the distance - loses in the line is a very common problem. For a 30A/12V array you need 3 gauge for 30 feet, 2 gauge for 40 feet, and 1 gauge for 50 feet. This is to keep the line lose to under the NEC required 3%.

[sjh7132]

Is that 10A into a 12v battery, or is that 10A from the panels at some higher voltage?

[Schweizer135]

DUH me! Another thought, the charge controller is protecting itself by not allowing the power out of it to exceed 15A. The panels may be fine but their power could be being choked off by the charge controller being undersized. 12A from the panels is about 15A to the batteries due to the voltage shift by the MPPT (panels 12A x 18V =~ 15A x 14.4V battery)

[wiboater4]

@Schweizer135 You might have something there. If you watch the amp gauge it does flip off for a second then come back up. I suppose I could just run the one small panel direct to the battery. If the battery gets full the charge controller should just reduce the other panels right?

[Schweizer135]

@wiboater4 Yes, if the charge controller puts the batteries on a float charge then the panels essentially sit idle, unlike a wind turbine that needs a dump load. You can use the load output terminals on that charge controller that will provide battery voltage to electronic devices up to 15A if the battery is above 12.1V or 12.6V based on the setting of switch 2. That way the power does not go to waste. See your manual on the load function.

[michael970]

10 to 12 amps is good .keep messing around with things and you will squeek more from it.I think a perfect single cell puts out like 4+ amps right.so figure you have 5 single cells the way you have it configured.so 20 open amps in perfect conditions.I may not be right but thats my 2 cents.TAKE CARE.and keep up the good work

[Schweizer135]

@michael970 Yes, so 5A x 18V x 5 panels = 450 watts from the panels ideally. A MPPT charge controller will reduce the voltage to ~14V for 12V battery bank charging and up the current to around 32A (even higher if the batteries are low). I've seen numerous DIY panels exceed their initial rating if they're in strong sun, or over 450w in this case.

[wiboater4]

@michael970 Thanks, How's your small wind turbine working?

[wiboater4]

I was just going over the manual for the morningstar , if I hook the solar panels into series for 24 volts I can go up to 400 watts. I'd need one more 36 cell panel though.

[Schweizer135]

OR ... since your turbines keep your batteries full then why not skip the solar charge controller and simply grid tie your solar watts to slow down your meter. This way every watt produced will provide a benefit to you. See vid pbj23-fu0E4 . Just be aware that grid tie inverters don't run at their "sticker" rating. One SF GTI 500 ($170) has proven to do 360w safely and one may be all you'll need. It should shave up to $10 off your elec bill each month, and more with tracking. Cheers ...

[wiboater4]

@Schweizer135  The turbines don't keep the batteries full. That's why I took the dump load off,because I didn't need it.

[wiboater4]

@Schweizer135 The turbines don't keep the batteries full. That's why I took the dump load off,because I didn't need it. The advantage of using the battery bank is haveing free power overnight when the sun is down. :)

[wiboater4]

@Schweizer135 The SF GTI your referring to , is that the sun 500G? and if it is where did you see it for $170. I saw a 250 watt for that price on ebay but the 500 watt is around $220. with the shipping. Micheal1970 is running 3 of the 500 watters now.

[Schweizer135]

@wiboater4 No, the SF GTI 500 is another unit sold by the ebay seller using-gods-free-energy but it looks like there is none listed currently. Did you see my note on wire size? What are your thoughts?

[wiboater4]

I have the 2 larger panels are divided into 2- 18 volt panels. only 36 cells each are in series on those. So it's like having 5 of the smaller panels. Just had to do it that way because of the used glass sizes. It should be about 450 watts total (2.4 to 2.6 watts per cell) if everything was 100 % but I'm sure I have some loss from the glass I'm using and probably a few other things. I appreciate your input I'm new at this and any help is welcome.

[Schweizer135]

@wiboater4 OK ... it's very good you split those 72 Cell panels into two 36's.  If you now wire all five 18V ones in parallel you will do very well but likely will instantly exceed the 200w rating on your charge controller. I recommend the Rogue MPT-3024 which will give MPPT charging of a 12V battery bank of up to a 418w array output (~30A at 14V charge voltage). Get your money back on the Morningstar, add $50, and you'll be set. The 3024 has a great digital panel too. Highly rated.

[wiboater4]

@Schweizer135 They are all hooked in parallel now. Have been for about 2 months. so far I haven't had any charge controller problems since I'm only getting 10 to 12 amps and am good to 15 amps with the controller.

[Schweizer135]

@wiboater4 Hmm ... something is holding it back. Might check the performance of each panel. One weak one will drag all the others down. You should see at least 75% of the "rated" output in full sun. The glass is not a huge factor (~5% at most). Good luck.

[wiboater4]

@Schweizer135 You mean I should check the voltage of each panel seperately unloaded?

[Schweizer135]

@wiboater4 Yes, the unloaded test in clear sun would indicate if some cells are shorted. Then I would test each one individually charging the battery (make sure the batteries need charging) and measuring the current accurately with a meter. On a clear sunny day each 36 cell panel should read the same current output if they are at the same angle to the sun. Today would have been a good day to test.

You have done a nice job on your panels, by the way. Did you make the frames?

[Schweizer135]

Another thought, at 12V that MPPT charge controller is only suppose to do 200w.

[wiboater4]

@Schweizer135 I haven't had any problem with it kicking out so maybe I'm not getting that much wattage. I'm feeding into 8- 6 volt golf cart batteries.

[Schweizer135]

If these are 5" cells and you have 180 of them then don't you have a 400w system? And since you are using the Sunsaver 15L you likely have all 3 panels in parallel (so the Sunsaver input voltage is not exceeded) which is going to cause your 2 big panels to operate at the voltage of the small panel (18V), thus you're only getting 156w (the same as 3 36 cell panels). If this is the case then unhook the small one until you can add a 2nd 36 cell one in series with it. Hi from MN.