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EMPIRE231

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That shouldn't hurt current flow, unless you're pushing 100A or something. How are the wires connected, soldered?

I'd recommend putting a strain relief, edging or a rubber grommet on that hole the wires are passing through. Eventually vibrations will chew through the insulation and short something out.

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Thanks for all the help so far...

another question for the experts...  On my solar meter display, it shows me sometimes   40W 2.8AMPS etc ... I am assuming this is what the solar is charging my batteries at... I have seen it as high as 200w, 10AMPS and around that neighborhood.  I am assuming this thing controls how much juice is being pumped to the batteries, depending on how bad they are depleted?  I have not ran these batteries down yet or done any heavy use, but should I expect to see much higher readings on the meter after a night of running the batteries down? (pretty sure I have 600W + of panels)

 

also sometimes it will read PWM and a percentage after that.... what does that translate to?

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54 minutes ago, EMPIRE231 said:

Thanks for all the help so far...

another question for the experts...  On my solar meter display, it shows me sometimes   40W 2.8AMPS etc ... I am assuming this is what the solar is charging my batteries at... I have seen it as high as 200w, 10AMPS and around that neighborhood.  I am assuming this thing controls how much juice is being pumped to the batteries, depending on how bad they are depleted?  I have not ran these batteries down yet or done any heavy use, but should I expect to see much higher readings on the meter after a night of running the batteries down? (pretty sure I have 600W + of panels)

 

also sometimes it will read PWM and a percentage after that.... what does that translate to?

The only real way to answer that is to run them down and then see what it does on a full sunny day so you get a good base line.  If they are depleted and your facing the sun you should get your max input.  

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Alright, so after my first weekend out in the desert with the trailer..... I don't think this setup is working to it's potential.

The highest I ever see the solar charging at is about 120-200w and around 10-12 amps.  I was assuming that maybe it only produces as much as it needs, as the batteries are pretty much always full.  This same day, my motorhome batteries decided to die on me.  The sun was out in full force, so turned on the inverter in the trailer, and plugged my motorhome into the trailer which started charging my motorhome batteries.  According to the readout on the magnum controller, I was drawing a little over 100 amps all together.  During this time, the solar controller still only showed about 150 watts and 10 amps or so.

 

after a minute or two, it actually shut off the inverter (pretty sure it was because of the low battery cutout setting) because when it is pushing big amps, I see the voltage reading on the magnum controller dropping to 11.7v or so.  Right after it shuts out and there is no load, it goes back to 12.7.

 

so the few questions I have..... 1.  should I turn off the low batt cutout on the inverter?   2. How do I determine if my solar charge controller is bad, or if the panels are just not producing the power? (estimated about 600w of panels up there.

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@r3meyer @socaldmax

Yo guys, not sure if you saw the post above.....

But should I not have the lowbatt disconnect setting turned on?  It's causing the inverter to shut off under load (battery signal dropping) but batteries are still pretty full

is there a way to test what the solar panels are producing as they enter the solar charger with a harbor freight style multimeter?  Since I am not seeing the solar controller charging higher that 200w @ 10amps while under a load... it makes me think either the solar charge controller is not working right, or the panels aren't producing what they should be producing.  This system is supposedly about 2 yrs old, 4 panels up there and it was a on a full sunny day. 

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Yikes, 10amps is garbage.  Can you confirm the panels and get a picture of the sticker on the underside?  Do you know if they are wired in series or parallel?  Easy way to check is under full sun put a meter on the + and - coming from the panels on the roof before they go into the solar charger and report back the voltage.  Its possible you have a shorted panel or a weak connection hindering the charging.  

Which PMW morning star do you have?  Dont know if I ever asked that.

12v is the cut off for lead acid. Thats the 50% mark.  Once you hit that you need to get them all the way back to 100%.  If all your seeing is 10amps then based of a charging calculator for lead acid you would need 28hrs of a 10amp charge.

You mentioned the batteries are full.  How did you come up with this.  When you turn the gen on what rate do they charge at?

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Your low battery cutoff should be around 11.7v or so. If your batteries are sagging under load that badly, they're either old or you need a lot more. I think you posted earlier that you were drawing 100A out of them. That's quite a bit for only 4 gc batteries.

As for your solar output, yes you can disconnect the solar panel wires from the controller and check for Voc and Imp. Both should be pretty close to the published numbers. If they're more than 25% lower, then you might have some shading or 1 or more bad panels or bad  connections. 

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5 hours ago, r3meyer said:

Yikes, 10amps is garbage.  Can you confirm the panels and get a picture of the sticker on the underside?  Do you know if they are wired in series or parallel?  Easy way to check is under full sun put a meter on the + and - coming from the panels on the roof before they go into the solar charger and report back the voltage.  Its possible you have a shorted panel or a weak connection hindering the charging.  

Which PMW morning star do you have?  Dont know if I ever asked that.

12v is the cut off for lead acid. Thats the 50% mark.  Once you hit that you need to get them all the way back to 100%.  If all your seeing is 10amps then based of a charging calculator for lead acid you would need 28hrs of a 10amp charge.

You mentioned the batteries are full.  How did you come up with this.  When you turn the gen on what rate do they charge at?

Got it, so I would just be checking for total voltage? I will try that on our next sunny day , prob thurs or Friday. 

I have the Morningstar charger which is PWM rated at 40amp I believe. And I adjusted the 7 buttons to the correct settings. It showing absorption charge and float at the correct voltage. 

I’m assuming they’re full because at night, the reading on the meter for the solar charger is 12.8+ volts  and I even added battery sense wires to have a more accurate reading  

 

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5 hours ago, socaldmax said:

Your low battery cutoff should be around 11.7v or so. If your batteries are sagging under load that badly, they're either old or you need a lot more. I think you posted earlier that you were drawing 100A out of them. That's quite a bit for only 4 gc batteries.

As for your solar output, yes you can disconnect the solar panel wires from the controller and check for Voc and Imp. Both should be pretty close to the published numbers. If they're more than 25% lower, then you might have some shading or 1 or more bad panels or bad  connections. 

At the time I got that 100amp reading. That was what I was seeing on the magnum controller in the trailer. That was right after I flipped the inverter on, and plugged my motorhome into it to charge the motorhome batteries. (Which the motorhome has a magnum inverter / charger as well. 

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I just read you have a PWM controller. I think what you're seeing now is exactly why I never recommend a PWM controller. They do not convert the high voltage/low current output of the solar panels into the low voltage/high current power into the batteries. They are "chopper circuits." They chop the voltage (let's say 48 v) down to 13 or 14v for the batteries. In the process, you lose a lot of the power. The circuit is on for 29% of the time, and off for the other 61% of the time. The power produced during that 61% doesn't pass through the controller.

Assuming your panels are 24v and are all connected in parallel, the PWM controller is "chopping" the voltage down to 14v and losing the power in that additional 10v. If whoever installed the panels connected them in series/parallel, then they might be putting out as much as 48v. and the PWM controller is "losing" the other 34v of power at whatever amperage the solar panels are putting out.

MPPT controllers actually calculate the maximum power point of the solar panels and convert that voltage (let's say 48v) and current (let's say 10A for a total of 480w) down to 14v at 38A. They're roughly 96% efficient, so you'll actually get about 36.5A of current into your batteries instead of the 10A you're seeing now.

That's assuming there aren't excessive cable losses, shading of the panels or damaged/poor performing panels. The big difference in output is why I always recommend MPPT controllers. Back when "12v" panels were putting out 16-17v at their max. power point, PWM controllers didn't lose nearly as much of the power, but now that panels are getting higher V and lower A (some of the ones I sell put out 47v - 65v) they have lower cable losses and the MPPT controller can efficiently convert the high V/low A output into low V/high A power into the batteries. The newer MPPT controllers can handle 100v or 150v solar input. This allows you to connect the panels in parallel/series strings up in the 90 - 120v range, allowing more efficient conversion and lower cable losses.

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On 11/20/2019 at 12:30 AM, socaldmax said:

I just read you have a PWM controller. I think what you're seeing now is exactly why I never recommend a PWM controller. They do not convert the high voltage/low current output of the solar panels into the low voltage/high current power into the batteries. They are "chopper circuits." They chop the voltage (let's say 48 v) down to 13 or 14v for the batteries. In the process, you lose a lot of the power. The circuit is on for 29% of the time, and off for the other 61% of the time. The power produced during that 61% doesn't pass through the controller.

Assuming your panels are 24v and are all connected in parallel, the PWM controller is "chopping" the voltage down to 14v and losing the power in that additional 10v. If whoever installed the panels connected them in series/parallel, then they might be putting out as much as 48v. and the PWM controller is "losing" the other 34v of power at whatever amperage the solar panels are putting out.

MPPT controllers actually calculate the maximum power point of the solar panels and convert that voltage (let's say 48v) and current (let's say 10A for a total of 480w) down to 14v at 38A. They're roughly 96% efficient, so you'll actually get about 36.5A of current into your batteries instead of the 10A you're seeing now.

That's assuming there aren't excessive cable losses, shading of the panels or damaged/poor performing panels. The big difference in output is why I always recommend MPPT controllers. Back when "12v" panels were putting out 16-17v at their max. power point, PWM controllers didn't lose nearly as much of the power, but now that panels are getting higher V and lower A (some of the ones I sell put out 47v - 65v) they have lower cable losses and the MPPT controller can efficiently convert the high V/low A output into low V/high A power into the batteries. The newer MPPT controllers can handle 100v or 150v solar input. This allows you to connect the panels in parallel/series strings up in the 90 - 120v range, allowing more efficient conversion and lower cable losses.

So haven’t had enough sun to test total volts coming in yet, but while on a ladder trying to figure out a roof leak... I spotted this wiring. Not sure if this helps wether it’s series / parallel?

10502A78-A9C4-4322-918A-2D5FB1C1F751.thumb.jpeg.580b41c9563b5819df8d8ed4b60e2b98.jpegDE40A417-B24E-4DCA-AF9E-14DDF8A6C2C3.thumb.jpeg.23e0108b1b680aae8238f633e9656437.jpeg

Edited by EMPIRE231

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Those are parallel connectors. You might have all 4 panels in parallel, or you might have 2 strings in series/parallel. The way to tell is if you see 3 of those parallel connectors on the roof, or you test the voltage coming into the solar controller and compare it to the specs of the panels. For example if the Vmp of the solar panels is 27v and you see around 54v, then you know you have them in 2 series strings. If you see 27v, then your panels are all in parallel. 

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Steve. is there a brand and model of the mppt you recommend these days?  for like 1 to 4 panels?

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11 hours ago, EMPIRE231 said:

So haven’t had enough sun to test total volts coming in yet, but while on a ladder trying to figure out a roof leak... I spotted this wiring. Not sure if this helps wether it’s series / parallel?

10502A78-A9C4-4322-918A-2D5FB1C1F751.thumb.jpeg.580b41c9563b5819df8d8ed4b60e2b98.jpegDE40A417-B24E-4DCA-AF9E-14DDF8A6C2C3.thumb.jpeg.23e0108b1b680aae8238f633e9656437.jpeg

This does not really tell us much other then you have good connectors.  As Dmax mentioned testing the wires coming off the roof will give you a better answer.  One thing with solar is if they are in series, any small part of a panel that is shaded will hinder output badly.  I can see the one panel has dirt built up in the corner.  I like to get on the roof when I first get to camp with a squeegee and a water bottle with a hole poked in the cap.  I give them a quick cleaning.

In preparations for my next trip I was looking at my charging history from last weekend.  My solar (735w) only saw 400w max with my Victron Mppt 100/50.  Highest I have seen reported is 657w in June.  This is a direct result of the sun being lower in the sky.  So your PWM charging results might be correct.

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5 hours ago, John@Outfront Mtrsprts said:

Steve. is there a brand and model of the mppt you recommend these days?  for like 1 to 4 panels?

Victron is top of the line.  Next I would go with Renogy.  Reason is both allow for bluetooth connection with your phone.  You can program and see status with the click of the app.  Both allow the use of Lifep04 when you decide to make the switch.  If you can stick to 30amps worth the price is very reasonable. 

 

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Can I buy connectors like this? I have a single panel and need to add the second panel I got from@socaldmax.

10502A78-A9C4-4322-918A-2D5FB1C1F751.thumb.jpeg.580b41c9563b5819df8d8ed4b60e2b98.jpeg

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1 hour ago, L.R.S. said:

Can I buy connectors like this? I have a single panel and need to add the second panel I got from@socaldmax.

10502A78-A9C4-4322-918A-2D5FB1C1F751.thumb.jpeg.580b41c9563b5819df8d8ed4b60e2b98.jpeg

Look up MC4 connectors.  You can get them in a ton of different configurations.

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I have 3 each 315 watt panels going to a Victron 150/70 mppt charger to 4 100ah lithium batteries and a magnum 2812 inverter. my question is when I wire the panels do I wire them in series or parallel ?  what will give me the most.

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4 minutes ago, bigray800 said:

I have 3 each 315 watt panels going to a Victron 150/70 mppt charger to 4 100ah lithium batteries and a magnum 2812 inverter. my question is when I wire the panels do I wire them in series or parallel ?  what will give me the most.

You have an odd number of panels. You must connect them in parallel.

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Okay, sun should be shining this weekend... I will get the total volts reading before the charger, and I will get up on the roof, to unbolt one panel and get a glance at the specs on the sticker.

I was hoping to find info on the panels from the serial numbers listed on the solar side, but had no luck with that.

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6 hours ago, bigray800 said:

I have 3 each 315 watt panels going to a Victron 150/70 mppt charger to 4 100ah lithium batteries and a magnum 2812 inverter. my question is when I wire the panels do I wire them in series or parallel ?  what will give me the most.

Parallel is always better for a system that will receive partial shading via roof vents, ac unit, tree etc.

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So I finally got up on the roof of this stacker, and here is what I have. I only unbolted one panel, but I’m assuming they are all the same. I measured volts going into the charger and I got around 20v. I gave the panels a good cleaning (very dirty) and will check hem again in some sunshine tomorrow. 

And I saw 2 more of the parallel connectors. So total of 4. 

E0E144AA-326B-421F-B1E6-93DEE9570C9A.thumb.jpeg.7234bfb9c6a2e74ece813eeeb32da357.jpeg35E5ACFF-6FFC-40EE-8D38-50CAF2659BBA.thumb.jpeg.58fc98345f5a94f4fb2dc0bd96b41931.jpeg

Edited by EMPIRE231

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Pics and info above

so I never saw over 20 volts coming into the charger.... peak sun, with clean panels.  I am not sure how to test amps coming in, but I am assuming these panels are wired in parallel based off what I have learned so far.... so I would think I should be seeing more than 10-11 amps and 100-200 watts on the display of my solar charger.  during that peak sunshine I let the air compressor cycle for a while to draw some juice, and never saw more than 125w and 10 amps coming in on the display. 

from doing a google search on the panels, it looks like someone paid a pretty penny for this setup.

 

@r3meyer  @socaldmax

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I would recommend numbering the frame of each panel 1-4 so you can keep track of them. Then one by one, disconnect them from the rest of the system and check the voltage, then check the current of each one and write it all down. Then you can see what they're actually producing vs what they are supposed to produce. You might have 1 panel dragging them all down, or 2, 3 or all 4 of them producing low output. You won't know how each one is performing until you measure them all.

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@EMPIRE231

What I would do from this point is at high noon use a DC amp meter and check what you are getting from each panel.  Most meters will only do AC amp so you will need to see if yours will read this.  If you dont have one they are very valuable tools to have.  You don't need to disconnect anything.  You can simply clamp it over the top of each panels + lead as it comes out of the panel.  They should all be almost exactly the same with zero shading.  Label and write down each panel's amp output.  Then go down to where it enters into the controller and clamp your meter over that + lead and see what you have.  You should have (very close to it) the total of all 4 panels amp output.

Next clamp the meter over the output side of the solar controller.  Record this number.  This will help us figure out what you have going on.

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