Ths CC Sufficient? Renogy Rover 20A 12V/24V DC MPPT 8.38A Panels 12v

[UptownSport]

Thinking was if i were to ever get a second 8.38A 12v panel, a 15A CC wouldn't be high enough (8.38x2=17.76A)

Or, could I just get a 15A, and install a second panel in series (I think I have that right) and use the many Morningstars MPPT 15A?

Sounds like Morningstar is the Michelin of Charge controllers, and I worry that Renogy price is a little too good to be true.

Thanks in advance, sounds like Charge Controllers are a bit of a contention here, so not at all looking to start anything!

 

[John61CT]

Yes, many feel those very-cheap SCs are fine.

I like Victron MPPT, their 75/15 is $100.

When MPPT are that cheap, I prefer to use more of them matched to higher-voltage single panels, rather than putting multiple panels per SC.

This is not only often cheaper, but gives redundancy and ideal handling of partial shade issues.

But others will disagree.

 

[jimindenver]

What panels are you speaking of and what controller? A single 270w 24v panel is the rated limit for a 20a MPPT controller. I use Morningstar now and have used Eco-worthy for 5 years. Renogy sells rebranded EP solar MPPT controllers so you may get a better deal on a newer model from them.

 

[Wabbit]

I like my Tracer BNseries w\MT-50 controller, but if I had to do it again, I wouldn't go this route. It works better than that PWM I had, but it glitches sometimes and at night I have a phantom .2v - .5v reading as input from solar panel. Others have also had this issues along with slow tracking changes. When I looked into my phantom loads, it led me to YouTube and videos there talking about the same thing. Just FYI.

 

[UptownSport]

Thanks- So I can put a 2nd 8+A panel in and NOT need over a 15A MPPT (ten amp, actually) controller, if they're in series?

Just don't want to go off half cocked and later say 'You idiot! You shoulda just ...'

It's a 150W Renogy, Jim. Maybe I should already say 'You idiot, why did you get that?' LoL

 

[jimindenver]

Thank you. You will need a second 150w panel like it to use them both with a MPPT controller. In series they will over panel a 20a MPPT meaning you are not getting all of the output. Some makers say it is ok but I can tell you that it produces a lot of heat personally. Once it is hot it will limit output to protect itself so you will be getting even less. I would suggest at least a 25a MPPT controller. You would have more options at the 30a level.

 

[UptownSport]

Yikes! ?
This, then? Not sure why it's so much less (relatively) than competition.

Renogy Rover 40A 12V/24V DC MPPT Solar Charge Controller for Battery Regulator

Not telling anyone where I park ... And i'm starting ExpensiveRVLiving.com

 

[Wabbit]

...Not telling anyone where I park ... And i'm starting ExpensiveRVLiving.com...

That got a chuckle out of me. Pretty funny!

 

[John61CT]

Better off with two Victrons, and just because there exist $25 controllers doesn't mean the better quality ones are "expensive".

You could start with one at $100 if you like yes overpanelled but no chance of hurting it, then if you want to compare overall charging performance buy the second one from a good-return shop, you're only out shipping cost if you decide just one's OK.

 

[jonsun]

I just got a renogy clone and IDK about it. watching it last night voltage jumps from 13.x to 16v (max setting) and the battery meter shows it half empty. It was being charged by converter and definitely full. Then during the day it will show it as full but continue to climb in voltage well past the absorption set point. I pull all load off battery and disconnect the panels battery hovers at 12.75 and it meter shows it at 75%.

I was going to make my own thread on it or call customer support soon. I wish I went with the victron its just the price jumps way up when you get the 20A+

oh another thing the 20a has max input of 260w

 

[jonsun]

I like my Tracer BNseries w\MT-50 controller, but if I had to do it again, I wouldn't go this route. It works better than that PWM I had, but it glitches sometimes and at night I have a phantom .2v - .5v reading as input from solar panel. Others have also had this issues along with slow tracking changes. When I looked into my phantom loads, it led me to YouTube and videos there talking about the same thing. Just FYI.

this is whole nother issue with mine. it's phantom charging the battery. It'll will be full by 2pm but as soon as sun sets and loads kick on (fridge) battery drops to 60% immediately like its sulfated. If I charge off the inverter then unplug it the battery easily goes all night.

 

[John61CT]

Didn't you buy from a source with at least short-term 100% NQAMBG?

The Victrons don't limit input watts, just clipping the output, 75/15 at 220w for 12V, 440w for 24V.

Very rare peak conditions for a panel to actually output rated watts anyway.

 

[UptownSport]

Ok, thanks, very helpful if i understand correctly, that Victron would take input of a planned second panel, just not deliver full output if both panels were operating at max efficiency?

 

[John61CT]

Not efficiency as such.

Overpanelling means peak output would be clipped, but average output per SC higher overall and in normal suboptimal conditions, e.g. faster charging earlier in the day.

Getting the second controller is spending $100 to get every last possible watt out of the panels in peak conditions

 

[jimindenver]

this is whole nother issue with mine. it's phantom charging the battery. It'll will be full by 2pm but as soon as sun sets and loads kick on (fridge) battery drops to 60% immediately like its sulfated. If I charge off the inverter then unplug it the battery easily goes all night.

This sounds like the controller is not holding absorb voltage long enough to fully charge the bank. Over time you get progressive capacity loss.

 

[frater secessus]

I like my Tracer BNseries w\MT-50 controller, but if I had to do it again, I wouldn't go this route.

My A series tracer definitely tracks changes faster than my BN.

 

[UptownSport]

Getting the second controller is spending $100 to get every last possible watt out of the panels in peak conditions

'Overpaneling'
Thanks, makes sense.
Victron from a 100% seller for und $100

I guess us guys can't put dual 4 barrels on stuff anymore, so we go to ... Big Solar.

Does Weiand make a 2x4 for the Mopar 3.3??

Srsly, thanks again, lost in wood w/o a compass