Added Third Panel in Parallel no increase in Watts, what am I missing?

[saxon11]

Add my third 200w Renogy panel with my Victron 30amp controller. No increase when look at App (as matter of fact, it dropped - see screenshot). I wired them in parralel with using two sets of splitters.

 

[Mattb4]

Since panels do not push watts what is the state of your batteries and do you have any loads?

 

[saxon11]

load is approx 50w

 

[fratermus]

Add my third 200w Renogy panel with my Victron 30amp controller. No increase when look at App (

1. The increase would be most evident in charging Amps during Bulk, not Voltage input.* We are not shown amps input or amps output. We are shown shown load amps (largely immaterial) and panel voltage (possibly interesting but beyond the scope of this issue)
2. if the battery is {holding} the Float or Absorption setpoint you could attach the battery to a nuclear power plant and current would not rise. The bank will accept what it wants at a given voltage setpoint. The controller will meet demand exactly.**
3. if the controller is already maxed at 30A you could put 10 panels on it and it could still only make 30A. At 14.6v output the 30A controller will {output} ~438w, and at 12.0v ~360w.

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*panel voltage will move off Vmp when the controller is limiting current
** up to its ability to make power from the panels

 

[Charleswgibbs]

What battery voltage? A 12v bank with 30a controller will max out around 400w so it's possible you are already at the maximum output of your controller.

 

[crossy]

Minimal detail in the OP but ...

Voc of the 200W Renology panel is 23V so it looks like everything is full, hence no power increase.

Also, if you now have 3 x 200W panels on a 12V system you will need another charge controller as 30A @ 12V is 360W (2 panels was actually slightly over-panelled).

 

[saxon11]

i actually only have a 20 amp victron: https://www.amazon.com/Victron-SmartSolar-MPPT-Controller-Bluetooth/dp/B075NPQHQK

 

[Vigo]

Well you’ve gotten a lot of good info already. Now with all your ‘excess’ solar time to come up with more loads to run with your free energy, and increase your charge controller capacity.

 

[timselectric]

You can only get 20 amps max, no matter how many panels you connect to that SCC.

 

[saxon11]

I still think something is wrong here or I need to adjust Victron or a different controller.

I'm trying to run my pond air pump 24/7, it only pulls 60w. The idea is the battery get charged enough during the day to handle when sun isn't shing. Unreasonable?

I realize my Victron 20mp can't use all three of my 200w Renogy panels (600w) at once, but i dont need all of it. But when it's overcast or cloudy i get much more with three than one 200w panel, right?
Here are some screenshots I took right now from my Victron. Watching it was starnge it goes up and down (from like 20w to 0w). Thoughts or should I built a different type of system here. Seems like pretty simple use case for solar.

.

 

[MisterSandals]

If your battery is showing 3.92V, its dead.

Any info on your battery would help here. I suspect its old and looking for a final resting place.

 

[Vigo]

Yeah, the battery is the big piece being left out of your questions.

If for example you are trying to power a 60w load 24hr/day that is 1440wh. If you are getting 8 hours of sun and 16 hrs without sun in those 24 hrs, you have to produce all 1440wh during the 8 hours you have sun. 1440 / 8 = 180w on average that you need to make for 8 hours straight. You only need to keep 16 hrs worth of it in the battery, so ~1000wh.

Now fudge everything upwards by 50% to build in a large margin of error and account for inefficiencies in the system. You’ve got plenty of solar panel (you need ~200w on average and you have 3x that in raw panels) and your thinking is correct that having more panels makes you less susceptible to weather/conditions making you fall below your ‘required minimum’ over the course of the day. Your charge controller is sufficient because 12v x 20a = 360w and 14v would be even more, well above the 200w you need.

But.. do you have ~1.5kwh worth of battery? If you don’t already know, that would be a lithium battery the size of a large car battery, or TWO large lead acid batteries, etc. This area may be the main source of your problem.

 

[saxon11]

I'm using this 12v AGM battery. I do have two of these 12v 18ah lithium battery laying around I could swap into instead of the AGM. Thoughts?

 

[Vigo]

Even if you had all 3 of those contributing it would be borderline. The general advice with lead acid batteries is to only discharge to 50% or so to avoid having an irritatingly short longevity. That size of battery is probably rated somewhere around 120-140ah. Roughly 1.6kwh. Which means you’d be cycling it deeply on a daily basis and it would die pretty quickly. Volts X Amp Hours = Watt Hours so those 12v 18ah batts are 200-odd wh each, would need something like TEN of those, which is a terrible idea (more connections, more failure points, not the cheapest anyway).

If youve been trying to run that AGM in this setup you need to assess whether it’s still healthy enough to be used for something else after you remove it from this application, because it’s doubtful it has survived heathy enough to stay connected with the other batteries you will have to add to this setup, and to not cause more trouble with pack balancing than it’s worth.

If you can still warranty it that would be great, because that would save you one battery worth of money on the new ‘pack’. I would say two of those batteries in parallel would be marginal for this use and three would be ‘ok’. But, just one sufficiently large lifepo4 battery could also do this job well, and may give better value for money in terms of daily cycles given, per dollars spent.

Also, make sure and adapt all the vague numbers i used in my last post to your specific situation. 8 hours of sunshine is unrealistic and if the panels arent on a solar tracker most of the hours wont give peak production anyway. After assessing the need more accurately you may find you need a larger solar charge controller as well so you can push closer to 600w into the battery when possible, to make up for other times you’ll be making far less.

 

[justgary]

Not to mention that AGM isn't going to take more than about 0.15C for charge current anyway. If you have a 120Ah battery, that would be about 18 Amps. As the battery gets older it will take even less current due to higher internal resistance.

 

[timselectric]

I realize my Victron 20mp can't use all three of my 200w Renogy panels (600w) at once, but i dont need all of it. But when it's overcast or cloudy i get much more with three than one 200w panel, right?

Yes
This is called over paneling, and it's great for cloudy days.