Solar upgrade

[Foldbak]

So I was at the dealership talking shop with the GM and he started bitching about parts obsolescence. Having been a parts manager for a Volvo/Mack dealership (in another life) I understood his dilemma. I asked whatcha got? He said he had some solar panels and controllers that GOT to go. Long story short I got two 160 watt Zantrex panels and a Victron 30 amp controller. He made me a deal I couldn't refuse. Two panel, mounting hardware, Y adapters, controller and sealant for $600. Looks like I'm upgrading to 720 watts. I'll share pictures of the install.

[brycesteiner]

what kind of batteries you gettin'?

[Foldbak]

Originally Posted by brycesteiner

what kind of batteries you gettin'?

I already have 200 AH lithium. They're made by Temgot. Chinese made with built in BMS. I've had them for a year with my factory 400 watt solar and LPG Onan generator. It's been great but I want to able to boondock in overcast weather and run my gen less.

[Foldbak]

The install was a breeze. It took me about 2.5 hours to install 2 panels and the controller. I do have a question, my new panels are only producing 20 volts while my factory panels are doing 40 volts. I haven't looked but could they be wired in series? I'm going to have to get back up there and inspect..

[LeftOverParts]

If the Vmp of the new panels is greater than about 12 volts, sounds like they’re wired in parallel.

Nice install and system! You got a great deal too!

[KingRanchFan]

From your pictures of each controller settings, you have victron network only on one controller, therefore nobody knows what the others are doing. All three should be on the same network. The shunt will provide battery voltage to the controllers and eliminate your voltage drop. Your new panels are most likely are in parallel which is fine as shade won't kill the pair, but I would recheck the connections or try one panel at a time to test. You could also disconnect the panel and check each panels output voltage with sun on them. Should be about the same on each.

Also make sure to set each controller for same battery type, one was set to user defined and had different absorption voltage.

It gets addictive when you start doing solar, you keep adding and adding until you run out of space. LOL

[Foldbak]

Originally Posted by KingRanchFan

From your pictures of each controller settings, you have victron network only on one controller, therefore nobody knows what the others are doing. All three should be on the same network. The shunt will provide battery voltage to the controllers and eliminate your voltage drop. Your new panels are most likely are in parallel which is fine as shade won't kill the pair, but I would recheck the connections or try one panel at a time to test. You could also disconnect the panel and check each panels output voltage with sun on them. Should be about the same on each.

Also make sure to set each controller for same battery type, one was set to user defined and had different absorption voltage.

It gets addictive when you start doing solar, you keep adding and adding until you run out of space. LOL

All three should be on the same network. I don't understand this comment. Please elaborate.

[KingRanchFan]

I will try if I can describe what triggered my thoughts.

The screenshot of the 3 devices has the shunt battery voltage at 13.17 and my experience it should be very close to the battery voltage displayed from each controller if the network is functional. That is VERY VERY valuable to getting full charge. I would go to each device and verify the little network symbol is present on each device. This symbol is highlighted in RED and is not present on one of your controller screen shots. It's the little round thingy and has to be there.

The final observation was the battery settings were different for each controller, just see the selection and make them the same. I could be working from screenshots that are not what you have now, but I think you see one is LiPO4 and the other is User Defined and set at 14.40 absorption.

I sent a picture from my device list as it will show shunt battery voltage very close to the controllers.

Hope it helps, thanks Brad

[Foldbak]

Thanks for that explanation. I've networked all three devices and set both controllers to user defined 14.4 volts. Love this place!

[scottz]

Originally Posted by Foldbak

I do have a question, my new panels are only producing 20 volts while my factory panels are doing 40 volts. I haven't looked but could they be wired in series?

I am assuming you are referring to 20 Vmpp. That would be about the maximum voltage of a 12V nominal panel when it is under load (producing power). The other voltage you will see is Voc; this the the panel voltage open circuit; when it is not under load. When sizing your controller you need to consider Voc. IE: I have four panels in series, each panel is rated for 25.29Voc; my controller must be able to handle 4 x 25.29V; about 100V, so I have 150/60 controllers. You have 100/30 controllers so they can handle up to 100V.

If your two new panels are showing 20Vmpp, they are in parallel. If your factory panels are showing 40Vmpp, they are in series. This assumes your panels are 12V panels (they probably are but there are other possibilities). In one photo I see a single controller. In another photo, I see two controllers. Are your factory panels connected to one controller and your new panels connected to the other controller? If so, it does not matter; one system could be parallel, the other series; in both cases the output of your controllers will be 12VDC nominal. The only difference will be the amount of current carried between the panels and the controllers.

Note: When a solar power system is called a 12V system, that is the nominal voltage; you will never see 12V. Just like your truck is considered a 12V system, but you will measure about 12.8V on a battery and 14V+ when the alternator is running.

Here is a photo of the specs on my panels:

[Foldbak]

Both sets of panels are in parallel, that's what confused me.

[scottz]

If your factory panels are in parallel and indicating 40V, they are 24V panels.

Do your factory panels and your new panels each have their own controller? If so, you should be ok.

Here are the specs of a typical 24V panel.

[Foldbak]

That makes sense. Most likely 24 volt and yes I added a second controller.