diy solar

diy solar

please help! New panels putting out very little energy

I think I need to change that inverter/controller out in order to be able to be safe more days but I cant afford enough solar to prepare for the worst case. I can't hook all the panels up without more wires and "beefier" wires. I'm going to hook up just two to establish if it's in good repair. If it is, then I will either return or use it with the 5th left over panel if I cant get more panels to somewhat match which probably means looking at E-bay and used sites.

I want to do the best I can for my elderly family while spending around 500 more. I am sorry I have thrown out a few different options. Part of that comes because I was looking at the blue prints on this site. I looked at the 2000 watt plan and saw they only had 1000 watts of panels despite it being a 2000 watt plan. How does that happen? So that had me hoping I could do more with what I have somehow.

"If you have let's say a 24V inverter, you need a 24V battery bank."

Yes, so I bought two 12v batteries. but then had advice that I needed more so bought 2 more. I can do that, right?
What kind of batteries? Spec of the batteries?
 
Yes, so I bought two 12v batteries. but then had advice that I needed more so bought 2 more. I can do that, right?
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
 
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
For each battery to see the same amount of wires resistance, the positive wire from the charger should be moved to the bottom left battery positive, or you can move the the negative from the charger to the bottom right battery negative.
See Victron wiring-unlimited:
 
I have 5 panels total but said 4 cause I've been told you can't wire 5 in series parallel.

You can put as many panels in parallel as you want. However, there are practical limits when it comes to current and the charge controller capability.

And if you already have 2 batteries (wired in series to get 24v), you can certainly test that all in one unit to see if it works.
 
For each battery to see the same amount of wires resistance, the positive wire from the charger should be moved to the bottom left battery positive, or you can move the the negative from the charger to the bottom right battery negative.
See Victron wiring-unlimited:
I can do that.

On a completely overcast day my 4-355 watt panels produced around 1700-1760 watts when wired in serial-parallel. I've read say wiring in series can multiply watts. If so, what might these 4 panels produce if wired the same way on a Sunny day with the correct inverter and controller? And that blueprint on this sight saying 2000 watts but only had 1000 watts coming off 3 panels. Were they just referring to stored battery energy or is there something else.
 
when you have more than twp panels in parallel, you will need to install the fuse for each panel.
 
This seems like it could be a good match. same cell number and 350 watts is close to my 355. Both are mono. Perhaps they would sell me one for a good price. If the specs seem good and the listing says they are new. What do you think?

 
On a completely overcast day my 4-355 watt panels produced around 1700-1760 watts when wired in serial-parallel. I've read say wiring in series can multiply watts.

When/how did you measure that? Wiring in series does not multiply total watts output of the array. It just gives more watts for that string. You ultimately get the same number of watts no matter how you wire them.
 
I can do that.

On a completely overcast day my 4-355 watt panels produced around 1700-1760 watts when wired in serial-parallel. I've read say wiring in series can multiply watts. If so, what might these 4 panels produce if wired the same way on a Sunny day with the correct inverter and controller? And that blueprint on this sight saying 2000 watts but only had 1000 watts coming off 3 panels. Were they just referring to stored battery energy or is there something else.
355W x 4 = 1420W, so how did you come up with 1700-1760 watts? How did you measure that? Your numbers do not make any sense. May be you're saying 1700 ~ 1760Watthr (1.7 ~1.76KWhr) per day.
 
355W x 4 = 1420W, so how did you come up with 1700-1760 watts? How did you measure that? Your numbers do not make any sense. May be you're saying 1700 ~ 1760Watthr (1.7 ~1.76KWhr) per day.
After I originally hooked up the 4 panels in serial and parallel before hooking it up to the combo unit. I put a multi meter on it. It was completely overcast with smoke. The meter was fluctuating a lot but the high number I could catch repeatedly was 1740.
 
When/how did you measure that? Wiring in series does not multiply total watts output of the array. It just gives more watts for that string. You ultimately get the same number of watts no matter how you wire them.
After I originally hooked up the 4 panels in serial and parallel before hooking it up to the combo unit. I put a multi meter on it. It was completely overcast with smoke. The meter was fluctuating a lot but the high number I could catch repeatedly was 1740.
 
After I originally hooked up the 4 panels in serial and parallel before hooking it up to the combo unit. I put a multi meter on it. It was completely overcast with smoke. The meter was fluctuating a lot but the high number I could catch repeatedly was 1740.
That is not how you measure wattage. No idea what you were reading as that is not even a valid voltage reading.
 
That is not how you measure wattage. No idea what you were reading as that is not even a valid voltage reading.
I put the multi meter leads on the end of the positive and negative wire coming in off the solar array.
 
When/how did you measure that? Wiring in series does not multiply total watts output of the array. It just gives more watts for that string. You ultimately get the same number of watts no matter how you wire them.
would these panels be a acceptable match to mine, if I cant get A-1 solar to sell me less than 4.

 
I put the multi meter leads on the end of the positive and negative wire coming in off the solar array.
Your Multimeter cannot read power, it can read Voltage, current, resistance.
Same wrong reading you reported in your post #1"
"A day or two, later I went down to finish hooking everything up to the batteries. I checked on the volt meter the watts coming in off the panels and it was around 85". Which I explain on my post #18 that your Volt meter cannot read Wattage.
Please show us the pictures of your Multimeter. At this point I think you are not using your Multimeter properly and it will lead to confusion when trying to troubleshooting the system, i just do not understand why you keep reporting Wattage reading with your Volt meter.
 
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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.
 
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Oh, and just to clarify a couple of basics:
Wiring in series multiplies voltage (differential, tension)
Wiring in parallel multiplies amperage (current).
Watts are the product of current x voltage (in DC, in AC we use volt-amperes because of phase)
Theoretical values and specs are just that. Real-life mileage may vary, and it will :)
 
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