New Montana with solar flex. Need to add panel

[Rexerito]

I have a 30 amp. Jaboni Solar controller that was already installed with a 300w Jaboni solar panel on my new Montana 3231.

I have purchased an additional 300w Jaboni panel to add to the controller. and I have purchased two 100ah Battleborn batteries.

My question is... do I wire the panels in parallel or series? I am concerned that I will burn up the charge controller if I wire them wrong.

Thanks
Rex

Panel-
https://www.jabonipowerproducts.com/...t-solar-panel/

Controller-
https://www.jabonipowerproducts.com/...ge-controller/

[Daryles]

Good article more so for the math
https://solarpanelsvenue.com/mixing-solar-panels/

[Rexerito]

Thanks, but these are identical panels.

[jetskier]

Originally Posted by Rexerito

Thanks, but these are identical panels.

You need a larger controller. The 30A charger is only good to about 420W of solar input using a 12V battery bank. It doesn't matter if you wire the panels in series or parallel. You will exceed the 30A output of the controller feeding the batteries.

[brooks340]

I agree with other replies, you need a larger controller. Assuming you add the 300w, then 600W at maximum draw of 14v to your batteries is about 43a. Now you panels won't be 100% efficient but you should still have at least a 50a controller. Series config is going to keep you voltage higher but current lower. And each config has it's pros and cons for shading, etc. Do the math and keep the total voltage below the limit on your controller. Most MPPT controllers really don't like being over voltage.

[hemiallen]

I am confused by the numbers.

The Jaboni system on the super solarflex has 4 ea 300w panels, and 2 each -30w jaboni charge controllers ( when-or if they still don't have a single 60w charge controller Mfg to install, Matt was mentioning they will be making a 60w controller soon). Did they design the system improperly? I have notes, nit sure my source, that a 300w plus another 220w panel would max out the Jaboni 30w controller, I did this when I wanted to add another 300w panel to my solarflex. But again, not sure where I got that 520w max for the 30w Jaboni factory supplied charge controller. I need to put footnotes on my notes, lol.

To the OP, I would be talking directly to matt Wolkins
mattw@futuresalesrv.com

He designed both systems and should know what he designed. No offense to folks here replies.

Allen

[jetskier]

If Jaboni is designing their systems to allow 600W panels on a 30A controller, they are doing it wrong.

In my example, when my Solar input is 531W, the output current is 38.70A. That would be way over the 32A over current limit on their controller (according to the data sheet below).


Keep in mind, I ditched my Jaboni 30A controller for a Victron 150/85 for the example above.

[hemiallen]

Well, as of July 2020 it looks like the supersolarflex was 4-265w panels, and the 2-30w Jaboni's. I believe they recently upgraded (2021) to the 300w x 4 panels ( solarflex has just 1) and everything I read says they still used the 2x 60w Jaboni's.

I can't find anything that looks to be current information, but a couple folks just received their supersolarflex Montana's and may know what solar charging system is included with the 1200w of solar panels.

Allen

[ExPatNW]

Very interested to see if someone can provide this information. We are picking up our 2021 Montana with Super Solar Flex at the end of the month and honestly I cannot tell if we are getting 265W panels or 300W panels and same for the solar controllers. 30a (x2) does not seem to be enough. Clearly its unlikely 1,200W will ever be generated, but my rough math suggests the most the 2 30A controllers could manage is 840W - (70%). Happy to be educated!

[hemiallen]

you FOR SURE will get the 300w panels, unless they run out, lol

I had an outstanding email question with Matt and just now asked for an update, and also what W solar charger(s) will come with both solarflex and super solarflex

Allen

[Rexerito]

Originally Posted by hemiallen

you FOR SURE will get the 300w panels, unless they run out, lol

I had an outstanding email question with Matt and just now asked for an update, and also what W solar charger(s) will come with both solarflex and super solarflex

Allen

Thanks Allen- hoping I don't need to upgrade my charge controller. I just got my rig last weekend and they told me that I have the 300w panel. Please let us know what you hear back.

[Rexerito]

Any update from Matt?

[hemiallen]

Not yet

I believe he does a lot of installations, and expect it may take awhile longer from past replies.

I'll post as soon as he replies.

Allen

[djrich]

I have a 2020 3791 Super Solarflex. We started using it 9/15/20 and have been in it since then. Have not plugged in yet. Ours came with 2 30A Jaboni controllers and so we have two approximately 500 watt systems. I added another 1000 watts and used 2 30A Blue Sky controllers. The input to the Jaboni controllers is about 24vdc and the output is 14vdc. The Blue Sky controllers have about 17 vdc input (whatever the panels produce) and 14vdc out. So I have 4 500 watt solar arrays each on a separate 30A controller. I have such a mix because I had a deal on the add on panels and controllers. The only thing the batteries care about is the output from the controllers. If I were you, I'd add another 30A Jaboni controller and have 2 separate systems going to your batteries. Redundancy.

[rames14]

I have the Super Solar system. (4) 300 watt panels, (2) 30 amp Jaboni charge controllers. I think your math is wrong if you think Jaboni and Future Sales don’t know their stuff. Just walked through the system at Future Solutions last Thursday while having my BIM installed.

[kowbra]

Originally Posted by jetskier

If Jaboni is designing their systems to allow 600W panels on a 30A controller, they are doing it wrong.

In my example, when my Solar input is 531W, the output current is 38.70A. That would be way over the 32A over current limit on their controller (according to the data sheet below).


Keep in mind, I ditched my Jaboni 30A controller for a Victron 150/85 for the example above.

Sorry, but you are not looking at the specs of the Jaboni panel. Your panels are not the same voltage. They are not doing it wrong, at all.

According to the Jaboni specs, the 300w panel max voltage is listed as 32.26v and max current as 9.3 amps (300.18 watts). The math is clear that two of those panels would be under 20 amps and the provided 30 amp controller has room to spare.

This is in agreement with prior posts on this forum and information from Matt at Future Sales, all of which have suggested that adding one more panel is easily handled by the 30a controller, but adding a 3rd panel may be pushing it.

Brad

[jetskier]

Originally Posted by kowbra

Sorry, but you are not looking at the specs of the Jaboni panel. Your panels are not the same voltage. They are not doing it wrong, at all.

According to the Jaboni specs, the 300w panel max voltage is listed as 32.26v and max current as 9.3 amps (300.18 watts). The math is clear that two of those panels would be under 20 amps and the provided 30 amp controller has room to spare.

This is in agreement with prior posts on this forum and information from Matt at Future Sales, all of which have suggested that adding one more panel is easily handled by the 30a controller, but adding a 3rd panel may be pushing it.

Brad

You're missing part of the equation....The battery side current. Yes, the PV side is within spec in both voltage and current. When the controller regulates the battery voltage to 13.6 to 14.4 volts, the battery current is increased. P=V*I. P is power in watts. Pin=Pout (with minor losses). Substitute and rearrange equation.... Iout=Pin/Vout=Iin*Vin/Vout. 600W/14.4V = 41.6A > 32A or when floating, 600W/13.6V = 44A. Therefore, the current exceeds the 32A overcurrent on the battery output circuit. It's in their spec page!!!!! Even at 75% efficiency, you're over 31A outputting to the battery. I'm assuming they figure your not in the peak output very long and they're okay with that.

[kowbra]

Originally Posted by ExPatNW

Very interested to see if someone can provide this information. We are picking up our 2021 Montana with Super Solar Flex at the end of the month and honestly I cannot tell if we are getting 265W panels or 300W panels and same for the solar controllers. 30a (x2) does not seem to be enough. Clearly its unlikely 1,200W will ever be generated, but my rough math suggests the most the 2 30A controllers could manage is 840W - (70%). Happy to be educated!

In a perfect world, 2x 30a controllers would handle 1800+ watts. (24v system with typical voltages of ~30v). You have enough.

Brad

[kowbra]

Originally Posted by jetskier

You're missing part of the equation....The battery side current. Yes, the PV side is within spec in both voltage and current. When the controller regulates the battery voltage to 13.6 to 14.4 volts, the battery current is increased. P=V*I. P is power in watts. Pin=Pout (with minor losses). Substitute and rearrange equation.... Iout=Pin/Vout=Iin*Vin/Vout. 600W/14.4V = 41.6A > 32A or when floating, 600W/13.6V = 44A. Therefore, the current exceeds the 32A overcurrent on the battery output circuit. It's in their spec page!!!!! Even at 75% efficiency, you're over 31A outputting to the battery. I'm assuming they figure your not in the peak output very long and they're okay with that.

Perhaps that is true.
But, I'm not sure I understand... why are you rearranging the equation? I didn't quite follow all of that.

Thanks,

Brad

[jetskier]

Originally Posted by kowbra

Perhaps that is true.
But, I'm not sure I understand... why are you rearranging the equation? I didn't quite follow all of that.

Thanks,

Brad

You rearrange to solve for Iout.
Look at my blue Victron image above. If you multiply the PV voltage * the PV Current, it's the 531W. Now multiply the battery voltage * the battery current. It's slightly less ~ 509W. That's the internal losses in the controller. My controller is around 95-97% efficient. Jaboni's spec sheet states a 97% peak efficiency. So we're in the ballpark.


I think there's confusion on 18V or 24V panels. It really doesn't matter if you understand parallel or series configurations. In series configurations with different input voltages, you need the PV panel specs to have the operating current close (like within 2-5%). If you don't, it will operate at the lowest current for the panel in that string and your not getting the full output capabilities of the panels. For example, my 160W panels have an Imp=8.6A and Vmp=18.6V. The 270W panels have an Imp=8.77A and Vmp=30.80V. Voltages are summed and current is the lowest on the string. That's like 2% difference in current. Perfect for a series configuration. The short circuit current and open circuit voltages should be in the same tolerance as well. They matter for the max input voltage when you're well below the lab testing of 25°C. The reason I went this way was the Jaboni panel that came with the trailer was a 265W, the 270W I found nearly matched. I don't have the room on the roof for the wide panels with the two roof vents and 3rd AC I added. The 160W panels are narrow and fit on the sides around those obstacles.

Parallel is similar, but the voltages need to be close. Currents add.