diy solar

diy solar

please help! New panels putting out very little energy

Well, if she "put the multi meter leads on the end of the positive and negative wire coming in off the solar array", she was obviously measuring voltage. So it could be 17.4. Not particularly relevant.
A few point I would like to make. Personal opinions, obviously.

- Panels, they sell them everywhere. Why have them shipped from far away? Just buy locally.

- Technical specifications are all good and fine. Real life is more... real :·)

Four 300W panels (well, 2 if they are 12V and you need 24) plus (I guess) some 400 Ah of batteries, should be fine to run a 1000W A/C unit.
If you run it during the sun hours, and use the generator on overcast ones.
Even though, 300W, it's theoretical. Real-life, call it 150. Non-ideal angle, non-perfect radiation, heat...

Likewise, and in this case I see this as the crux of the matter, a 3KW inverter. To run 1KW.
Sporadically, fine. Continuously, for four hours... it won't like it, and above all you won't like it.
It will get extremely hot. The fan will be on all the time at maximum power. It will suffer and degrade.

It seems to me... as I've said, they do sell 24V evaporative coolers Not expensive.
That would take the inverter out of the equation and basically solve the problem.
Well VOC of the panel is 40V so if she reading 17.4V from the array then there is problem. At this I do not believe what she is reporting are correct. She need to provide the pictures of her setup and what are being display on the scc.
At this I sure like to know if she fixes the PV inoput Voltage to be at <70V max PV input and if the setup is even working at this point.
 
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Well, she seems to have 12V panels in series for 24 (it would help if we had clear specs of the whole installation, wouldn't it - I can't seem to find them). So if she measured one panel... and it wasn't open circuit... oh, anyway, it's confusing information at any rate. It would help to have clearer data.
 
Well, she seems to have 12V panels in series for 24 (it would help if we had clear specs of the whole installation, wouldn't it - I can't seem to find them). So if she measured one panel... and it wasn't open circuit... oh, anyway, it's confusing information at any rate. It would help to have clearer data.
See her post #60 for her panel spec.
 
Well VOC of the panel is 40V so if she reading 17.4V from the array then there is problem.

Right, that is why I said the reading made no sense (no matter whee you put the decimal point).

I still think that at this point the simplest thing to do is connect those two existing batteries in series and connect them to the existing all-in-one. and see if the inverter part works. If it does, then connect one or all of the panels in parallel to the solar input of the all-in-one to see if that still works. Once there is an actual working system, the next steps can be taken.
 
Yes, you can do that. You will have 4 batteries and will need to wire 2 pairs in series. Each pair then wired in parallel.

24v%20d.jpg
Can I do that if I end up keeping the current combo unit which is not MMPT? Most recent comment on this post makes me wonder if I dont need to put the money inot more panels. He claims the size of the inverter compared to the much lower wattage of the panels will make the inverter winge and make other noises/not work well.
Well, if she "put the multi meter leads on the end of the positive and negative wire coming in off the solar array", she was obviously measuring voltage. So it could be 17.4. Not particularly relevant.
A few points I would like to make. Personal opinions, obviously.

- Panels, they sell them everywhere. Why have them shipped from far away? Just buy locally.

- Technical specifications are all good and fine. Real life is more... real :·)

Four 300W panels (well, 2 if they are 12V and you need 24) plus (I guess) some 400 Ah of batteries, should be fine to run a 1000W A/C unit.
If you run it during the sun hours, and use the generator on overcast ones.
Even though, 300W, it's theoretical. Real-life, call it 150. Non-ideal angle, non-perfect radiation, heat...

Likewise, and in this case I see this as the crux of the matter, a 3KW inverter. To run 1KW.
Sporadically, fine. Continuously, for four hours... it won't like it, and above all you won't like it.
It will get extremely hot. The fan will be on all the time at maximum power. It will suffer and degrade.

It seems to me... as I've said, they do sell 24V evaporative coolers. Not expensive.
That would take the inverter out of the equation and basically solve the problem.

[EDIT] Actually, looking at the evaporative coolers... they seem to be all small and inefficient.
I can find quite a lot of full "split-unit" DC air conditioners, though.
Thank you for getting to the bottom of the reading I saw. I checked the meter and the decimal isn't lighting up anymore. I will go buy a new meter. The whole add a new multi split on dc is completely overwhelming right now. I need one thing at a time. I appreciate the outside the box thinking and that to some that would be the simpler route. It may turn into what I have to do, but I see solar as a way through a possible coming crisis. But, I can't even lift an ac unit and I can't spend money on that if I have to spend money to fix this system by either buying more panels or a different inverter/controller set up.
 
Right, that is why I said the reading made no sense (no matter whee you put the decimal point).

I still think that at this point the simplest thing to do is connect those two existing batteries in series and connect them to the existing all-in-one. and see if the inverter part works. If it does, then connect one or all of the panels in parallel to the solar input of the all-in-one to see if that still works. Once there is an actual working system, the next steps can be taken.
I agree, this is the first step.

Right now what I need is to know:
if 12awg cords and cables are sufficient to wire the 5 355W panels all in parallel.

The label on the back of the panels say to use 12 awg and makes no mention of serial or parallel, so I assume they are right,but we talked about needing beefy cables to do parallel, so looking for confirmation.

Also can I have different length y connector cables or do they all have to be the same length?

If the 12's satisfy our needs, I will go out today and attempt to get enough cables and fuses to hook the system up as it is today.
 
Right now what I need is to know:
if 12awg cords and cables are sufficient to wire the 5 355W panels all in parallel.

The label on the back of the panels say to use 12 awg and makes no mention of serial or parallel, so I assume they are right,but we talked about needing beefy cables to do parallel, so looking for confirmation.

Also can I have different length y connector cables or do they all have to be the same length?
The 12awg should be fine for the individual panels. But at some point they need to be combined. Wherever that is, the cable will need to be larger. The closer you run the panel cables to the equipment the better (for this configuration).

The individual panel cable length is not that critical. But as noted, if you combine them closer to the panel location, you will need larger awg cables going from the combiner to the equipment. How far are the panels from the equipment?

As an example, all of my panels are in parallel, But the farthest panel is only about 20 feet away from my equipment. The panels cables all go to a combiner (bus-bars) and from there I use 2awg cable to the charge controller that is only 2 feet from the bus-bars.

As for fusing the panels if in parallel, the reason for this is if you have a short in one panel/line, you won't have all of the current from the remaining ones flowing into it and possibly causing a fire. But for now if you just want to see if your equipment works, you can use one panel or parallel just two of them. Again, this is just to test the all-in-one to see if it was damaged earlier. If it does not work, it may be time for a new plan.
 
Well VOC of the panel is 40V so if she reading 17.4V from the array then there is problem. At this I do not believe what she is reporting are correct. She need to provide the pictures of her setup and what are being display on the scc.
At this I sure like to know if she fixes the PV inoput Voltage to be at <70V max PV input and if the setup is even working at this point.
The sky was completely covered and obscured by smoke. A few cable connections were not tight. Hoping that's all it was, yes?
 
The 12awg should be fine for the individual panels. But at some point they need to be combined. Wherever that is, the cable will need to be larger. The closer you run the panel cables to the equipment the better (for this configuration).

The individual panel cable length is not that critical. But as noted, if you combine them closer to the panel location, you will need larger awg cables going from the combiner to the equipment. How far are the panels from the equipment?

As an example, all of my panels are in parallel, But the farthest panel is only about 20 feet away from my equipment. The panels cables all go to a combiner (bus-bars) and from there I use 2awg cable to the charge controller that is only 2 feet from the bus-bars.

As for fusing the panels if in parallel, the reason for this is if you have a short in one panel/line, you won't have all of the current from the remaining ones flowing into it and possibly causing a fire. But for now if you just want to see if your equipment works, you can use one panel or parallel just two of them. Again, this is just to test the all-in-one to see if it was damaged earlier. If it does not work, it may be time for a new plan.
There is no combiner since it was just 4 panels. All the y cables lead into a 16 foot, 12 awg extension cable. The panels are tight up against each other end to end in tilt braces facing south. The panels are about 18-22 feet from the box. they can come closer but then one panel will be in shade a good bit of the day. The cables going from the box to the and from the batteries are 6 double stranded and 4 off the batteries back to the box.

So you think the16 foot extension negative and positive cables to be 4 awg?
 
I wouldn't worry about voltage drop there, really. The panels are rated for about ten amps. Theoretical. In practice, under good conditions, they'll probably give you 6-7. Under average conditions, say 4-5 - temperature really lowers output, and you say it's hot there, they're black... under not-so-good (overcast, etc.) conditions, next-to-nothing.
So call it 6A each - when they're really pumping. 24A total. Over 20 feet, you have a theoretical drop of less than 2.5V.
They churn out 35V or so, take 3, it's 32, you need... less than that for your controller to use them and charge at 24.

One note: if you want to enjoy your panels (hey, while you're at it ;·) get an analog ammeter and stick it between the panels and the controller.
Not as good as analog ammeters for wind turbines - those are really enjoyable ;·) but they're still pleasant to watch, and give you a pleasant visual reading.

On my "temporary" panel I have three. One for solar charge, one for 24V load, one for wind.
Let's see if I get get a picture (it's nighttime)... yeah well. Nighttime, bad phone... just to get an idea:

20210906_222914.jpg
 
I agree, this is the first step.

Right now what I need is to know:
if 12awg cords and cables are sufficient to wire the 5 355W panels all in parallel.

The label on the back of the panels say to use 12 awg and makes no mention of serial or parallel, so I assume they are right,but we talked about needing beefy cables to do parallel, so looking for confirmation.

Also can I have different length y connector cables or do they all have to be the same length?

If the 12's satisfy our needs, I will go out today and attempt to get enough cables and fuses to hook the system up as it is today.
So at this point did you even try to see if the simple setup (just two panels in parallel, one 24 battery bank, a small lod) with what you have is even working or not? It will be wasting time to talk about wire gauge/combiner/etc if the SCC/Inverter is not working. Show us the SCC/INVERTER display panel when you have the setup going.
 
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So at this point did you even try to see if the simple setup (just two panels in parallel, one 24 battery bank, a small lod) with what you have is even working or not? It will be wasting time to talk about wire gauge/combiner/etc if the SCC/Inverter is not working. Show us the SCC/INVERTER display panel when you have the setup going.
Here's an update. Couldn't get cords on labor day. Got a call back from the solar place on Tuesday and they want to review everything and help me rather than just make the cords for me. So, I have sent them all the specs and I am waiting to hear from them. They are not charging me anything to review and advise. So, why not let them design it? I also tested all the panels for volts and amps with a new multi-meter. They came in at 37 volts (compared to factory 40.6) and roughly 7 amps (compared to10.27) . It was after 3 pm and 106 degrees here, so maybe that's acceptable? I also tested the panel that I have never used and it tested the same. So, nothing I did effected them. If anyone has a way to test the inverter/controller short of hooking it up , I can do that.

Somewhat of a tangent: Today, the smoke is too strong here to be outside. It makes you throw up when it's this bad. Some of it gets in the house no matter what you do so you're nauseous and your eyes and throat burn all day. I live in a city. Just imagine what it's like for those living out in the woods. Hoping we get a wind to blow it out, but not likely. We have high temps again today, which tends to keep it from lifting. Tomorrow the heat breaks. Anyone who tells you CA is right to just let 10,000's of acres burn all summer long, is full of it. It never used to be like this before 5 years ago. CA rarely saw fires this far north. Now, I hate summers. We all do. Grateful we have not been evacuated here. That's worse.

Anyway, I have no cords; so can't do anything and if I did, the weather makes it impossible to go out.
 
They came in at 37 volts (compared to factory 40.6) and roughly 7 amps (compared to10.27) . It was after 3 pm and 106 degrees here, so maybe that's acceptable?

Sounds about right. Especially if there is a lot of smoke.

You should be able to test the inverter part by hooking up the batteries to unit. It does not "need" the panels to work.
 
I wouldn't worry about voltage drop there, really. The panels are rated for about ten amps. Theoretical. In practice, under good conditions, they'll probably give you 6-7. Under average conditions, say 4-5 - temperature really lowers output, and you say it's hot there, they're black... under not-so-good (overcast, etc.) conditions, next-to-nothing.
So call it 6A each - when they're really pumping. 24A total. Over 20 feet, you have a theoretical drop of less than 2.5V.
They churn out 35V or so, take 3, it's 32, you need... less than that for your controller to use them and charge at 24.

One note: if you want to enjoy your panels (hey, while you're at it ;·) get an analog ammeter and stick it between the panels and the controller.
Not as good as analog ammeters for wind turbines - those are really enjoyable ;·) but they're still pleasant to watch, and give you a pleasant visual reading.

On my "temporary" panel I have three. One for solar charge, one for 24V load, one for wind.
Let's see if I get get a picture (it's nighttime)... yeah well. Nighttime, bad phone... just to get an idea:

View attachment 63534
That does look like it would be fun. Soon.
 
Somewhat of a tangent: Today, the smoke is too strong here to be outside. It makes you throw up when it's this bad.
So far the awful fires in California this year have burned 2 million acres. Reminds me of the Summer of 2019/20 here in Australia. 46 million acres burned.

That's not some sort of stupid boast but to put into some context just how goddamn awful it was and I completely understand the smoke issue and just how horrible it can be. We had it for months. Stay safe and have an evacuation plan. Know exactly what your options are and have a kit ready to go with essential items.
 
I am posting the input from some solar installers that are now helping me. I thought it might be of interest. It agrees with the advice given here. There help wasn't sought but offered when I asked for them to help me by selling me cables:


See the wiring diagram below. This will be the easiest way for you to work thru the info-overload and common confusion. http://freesunpower.com/example_systems.php

Below is some tech explanation regarding the series/parallel debate.

The conclusion is:

Wire the panels in parallel.

Use a solar combiner, (breaker box) at the array

Use proper wire sizing from the combiner to the solar input of your all-in-one, (with appropriate breaker).

Installing the system in this configuration will be the way to test the components.



The explanation is:

The charge controller portion of your all-in-one is a PWM style. This requires the lower input voltage, (compared to an MPPT style). Therefore the PV, (solar panels) must be wired in parallel only.

The charge controller max input voltage is 70 VOC. The PV spec is 40.6 VOC, well within specs.

The “working” specs for the PV is 34.6 Vmp and 10.3 Amp (amps max power)

4 PV wired in parallel will create “working” specs of 34.6V and 41.2A, (total 1420 watts). This should be plenty of wattage for your loads. We can set up your solar combiner box to accept a max of 6 panels.

My wire sizing choice is based on a solar wire length of 20 or 30 ft, (from combiner box to the all-in-one).



Sure hope this helps.



Refer to the “example system” attachment:



The combiner can be 1 of 2 types:

Midnite Solar MNPV6 with 4 – 15 amp breakers, cost ~$210, in stock

Simple, unfused combiner at the PV array with 1 – 60 amp breaker near the all-in-one, cost $65, not in stock, ETA next week. You may be able to make this yourself, (refer to “images” attachment.

Wire size from the combiner to the all-in-one is 8 ga. stranded for 20 ft, 6 ga. stranded for 30 ft

‘F’ in the diagram, (input) should be a 60 amp breaker, ‘F’ output is not needed, (yours is internal).

Your all-in-one may not be designed for generator input.

Shunt and meter are optional.

AC breaker panel may just be a power strip.

1631134372500.png
 
With more than 2 panels in parallel, you should fuse them individually. Otherwise any short in one (or their line) will cause all of the current from the other panels to flow into them and could "possibly" cause a fire.
 
Before spending more money on the wires, combiner box, ect.
In my post #92:
"So at this point did you even try to see if the simple setup (just two panels in parallel, one 24 battery bank, a small lod) with what you have is even working or not? It will be wasting time to talk about wire gauge/combiner/etc if the SCC/Inverter is not working. Show us the SCC/INVERTER display panel when you have the setup going."
You fed 80V into the 70V max input of the SCC in the beginning so we have no idea if the SCC is damaged or not.
 
I ifinally attached the two batteries in series to the inverter/controller. I have no idea if this is how it should read or not. It doesnt tell me how charged the batteries are and I would think it should.
 

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