Help needed with setup.

[AlanT]

I am going to install my system on a RV. I have purchased a 60amp Renorgy Rover Charge controller, 3000W Renorgy Sine Wave inverter, 4 Renorgy 100ah 12v lithim batteries and 10 100w Renorgy solar panels.
Renorgy says I can only use 8 panels on this system. Can I use all 10 panels in 5 groups of 2 series?
If I understand correctly the 10 panels in 5 groups of 2 series will be 44v and 26 amps. If this is correct why will the 60amp rover not work.

 

[squowse]

What voltage are you planning on running at. 3000W is a bit much for 12V.
24V be better.
That list of gear would cost a fortune in UK and be incredibly bad value as well as fiddly to set up. So many panels - then you’ve got to keep 4 batteries in balance.

 

[sunshine_eggo]

2S = ~44Voc
5P = 26A

both should be in compliance with the Voc and PV Isc limits on the controller.

The controller may specify additional power limits. Those are often open to interpretation. Are they trying to establish an upper limit of the array, or are they indicating the max power output? The Chinglish is often not clear.

Lastly, 60A * 14.4V = 864W - you're barely over that, and 10 panels on an RV roof are unlikely to ever put out full rated current/power.

 

[squowse]

I am going to install my system on a RV. I have purchased a 60amp Renorgy Rover Charge controller, 3000W Renorgy Sine Wave inverter, 4 Renorgy 100ah 12v lithim batteries and 10 100w Renorgy solar panels.
Renorgy says I can only use 8 panels on this system. Can I use all 10 panels in 5 groups of 2 series?
If I understand correctly the 10 panels in 5 groups of 2 series will be 44v and 26 amps. If this is correct why will the 60amp rover not work.

The panels should be ok in 2 strings of 5 panels. Max pv voltage on that controller is 150V and the panels will be about 125v nominal

 

[Black Pearl]

I used to have 800 watts on my Rover 60, 8x100w panels, in a 12v configuration system. My array is on a roof. The roof pitch (degree) is almost perfect for my latitude, and gets full sun at solar noon. I never seen 800 watts coming in ever. Mid/High 600's, maybe seen very low 700's a very limited number of times in ~2 years.

I'd have to agree that its unlikely that you will never see 800 watts coming in from 8/10 12v 100w panels, especially on the top of an RV, assuming they will be flat.

The Renogy Rover 60 gives us 3 data points to work with in their literature. Voltage limit, Current limit, and Overall PV watts for your configuration - 12, 24, 36 ,48v - 800, 1600, 2400, 3200.

When I upgraded to 16 12v panels, seen as a 24v configuration by my Rover 60, that's when I started seeing 1.5 - 1.6k coming in regularly from the array, under optimal solar conditions.

I haven't frequented, nor posted here much till more lately (I spend most of my time reading), but this Renogy Rover 60, what are it's limits, has came up on here a lot as of lately.

I have another 8 100 watt 12v panels (spares), and a spare Rover 60. I do get tempted to find out what the limits of this specific SCC really are - haha.

Side note - someone posted some QnA back and fourth with Renogy tech support regarding this same topic on another solar forum. Didn't seem like they ever got any answers regarding direct full sun over paneling beyond what the owners manual has to say. The user was quite frustrated with the answers they continued to receive from Renogy.

Edited (2400/4800) bad napkin math

 

[sunshine_eggo]

The Renogy Rover 60 gives us 3 data points to work with in their literature. Voltage limit, Current limit, and Overall PV watts for your configuration - 12, 24, 36 ,48v - 800, 1600, 3200, 4800.

This is the part I was talking about "Chinglish."

I think it's a translation thing. It doesn't really make sense because 800W/60A = 13.3V, and it's definitely going to charge to a higher voltage than that. I think they mean to specify that you will get that output at those voltages, not that those are limitations on the PV array.

 

[Black Pearl]

I'm really not sure. I have yet to see an example of someone posting that they over paneled their entire array into the sweet spot, let alone daily, with a Renogy Rover 60.

It is kinda weird that let's say, Sigineer sells a comparable and more affordable SCC, and their literature specifically says all 3 data points that Renogy says, but they also specifically say that the Sigineer SCC has a built in current limiter.

I would like to add a 5th series string connected parallel into my current array. I would still be below the voltage limit, but would be over current. That would theoretically help solar output in the morning and evening, cloudy days, etc.

I have no doubt that the Sigineer could handle it, but for how long?

As for the Renogy, IDK, and for how long?

A couple of relevant links...

Over paneling a charge controller

My Renogy rover 60 has two limitations. No more than 150volts Vmp and no more than 3200 watts input. My panels have a Vmp of 20.4 @25degrees.

forum.solar-electric.com

Renogy Rover 60: is max panel power really 800W ?

A newbie Q: Renogy's specs say the Rover 60's max panel power for a 12v system is 800 Watts. Can it be connected to, say, a 1200W PV array and will it self-limit the input power to 800W? The reason I ask is that on a cloudy or winter's day the 800W panel may put out eg 75% (600W) while 75% of...

diysolarforum.com

 

[sunshine_eggo]

Are you Barry?

That thread again brings attention to the "Chinglish" in the manual. If you assume 800W is an input limit, why do they say, "PV Overcurrent: The controller will limit the battery charging current to the maximum battery current rating. Therefore, an over-sized solar array will not operate at peak power."?

If there's an 800W input limit, why do they even talk about potentially overpaneling?

The attempt to contact Renogy is comical. Why is anybody surprised that you get no useful answers from the company that sells it? You're talking to people with no technical knowledge using Google Translate. So many similar transcripts on this forum.

This uncertainty is why I choose to not buy cheap Chinese shit unless I don't care about reliability (yes, I have a couple, but the moment they fail, I will thank them for every second of effort they gave me up to that point and consider myself lucky I got anything out of them at all).

I can hang > 12kW of PV off my Victron MPPT 250/100 that's only capable of 5800W output, and it will be fine. Victron explicitly states that it will be fine provided the array never exceeds Voc (250) or the published PV input current limit (70A). In fact, in most installations, they recommend 20-30% overpaneling because in most cases, the array rarely outputs rated power and can easily be 10-30% less.

Wanna know a secret? The 70A isn't even a hard limit per Victron personnel at their support forum. It's simply the maximum current the built-in reverse polarity protection can handle. So... if I'm a dumbass and connect my PV backwards, the unit will protect itself provided the array doesn't send more than 70A into it. If I'm not a dumbass and I don't hook it up backwards, there's no official limit.

Back to the Renogy...

Since the MPPT is a load on the array, it doesn't really matter what the array is capable of putting out. The question becomes:

"Is my equipment so cheaply made that it can't handle it's 60A rating for more than a few minutes at high noon?"

If the answer is "Yes." I would propose you don't even try to hit 60A - more like 45A.

Given the documentation, overpanling is implicitly allowed as they indicate the excess power will be limited by the 60A output.

If I needed another string, I would install it. If I could orient it to maximize morning or evening harvest while keeping the peak output down, I would. If I couldn't I would do it and replace it when it blows.

 

[Black Pearl]

Nope, I'm not Barry - haha.

I just re read that thread, and given everything I am aware of, I'd guess the Rover 60 can handle a bit of over-paneling. Maybe ~10% - just a guess.

Sure was a wide variety of answers in that thread...

Location is probably another key component to this topic. I'm in Florida and have a fixed array, and get a lot of serious sun, as does Arizona.

Back to the RV, I already agreed that I really don't see any serious issue.

 

[AlanT]

Thanks everyone. I am going to give it a try and see if Renorgy can stand up to it. If not, I'll junk it and get something else.