"PV Power Overload" ; Midnite Classic's have this problem?

[Onlooker]

I have a few Midnite Classics but am using a Renogy Rover 40Amp in a small system at the moment... I'm in an area with lots of mixed shade, poor sun, etc etc..
To get the most out of my controller I have panels all parallel, and I've connected up 1000 Watts of worth to this charge controller.  Renogy is continuing to function, but on a bright sunny day(and low battery) it reports an Error "PV Power Overload" and outputs a reported 41 amps(My meter has it touching 45amp).   

Renogy Support: "The Rover Li 40A controller can take as much as 520W solar input power for a 12V system and 1040W for a 24V system. You have a 12V system, so 1000W solar input is way over the limit of the Rover 40. Please kindly reduce the size of solar array to 500W when you do get perfect sunlight exposure, otherwise, the controller may get permanently damaged. "

Does Midnite Classic have this issue?  OR any other MPPT you know of?  I thought the whole idea was they controlled the input/output and as long as voltage wasn't outside their input range, all was good.  Where I plan to use my Midnite classics is even worse solar conditions; I was thinking of connecting up 5-10 times solar panels needed to get enough power in a cloudy week to keep operating; If I do this, will a full sunny day cause problems for the midnite or will it be capable to only deliver its maximum rated output(temperatures/etc etc in consideration).

The Renogy seems to be throttling itself; at that 45amp peak it did hit about 56C temp; which I immediately put a fan on it, and it lowered to less than 41C.  I'm out of warranty on the Renogy and from all testing/appearances I'm thinking of ignoring Renogys maximum input PV; and instead add active cooling (Touched/checked all the wires, seems good); It is a concern...

No need to recommend going to higher voltage; I've committed to 12V a decade ago and unless I found a lasting economical(<$100) 24-56V 100-250Amp step down DC-DC Converter; I won't be raising battery voltage.

Example: Midnite Classic 250-CP; ~63amps; 63*12.8 ~ 800 Watts; I could see putting 4000+ watts of panels on it.  a Classic 150 I've been running for 10 years or so, has ~1500 watts on it, and I've had a whole month where the peak output was on any given day less than 200 Watts; I am musing about covering a roof/woodshed with 6000 Watts($1500) of panels to get 500-1000W during those conditions. 

[ClassicCrazy]

I can't speak about your Renogy controller - no idea how it is designed. Sounds like a pwm controller ? I think I have read about the Classic being able to handle more than the rating of PV watts in. But you will probably want to search the forums here to find those discussions.
I am curious - what do you use over 100 amps of 12v dc for ? Starting cars ?
Larry

[Onlooker]

I am curious - what do you use over 100 amps of 12v dc for ? Starting cars ?

I have a supply of 12V to 120V inverters; back before the prices of 24-48V DC inverters approached parody.  That is the main thing, ~1500W/12V = 125Amp+20% inverter losses+Surges... Adds up.  Then my place is dual wired; 12V: fridges, pumps, lighting, inet/computers, charger(from when on generator).

[ClassicCrazy]

I am curious - what do you use over 100 amps of 12v dc for ? Starting cars ?

I have a supply of 12V to 120V inverters; back before the prices of 24-48V DC inverters approached parody.  That is the main thing, ~1500W/12V = 125Amp+20% inverter losses+Surges... Adds up.  Then my place is dual wired; 12V: fridges, pumps, lighting, inet/computers, charger(from when on generator).

Okay - always choices to be made.
Life sure is easier with the higher voltage which is what I went to. Especially for the PV input because wire size is so much easier. 
I use a Samlex 24 to 12v converter here for my 12v loads. But just also added in a 48v system. From what I see the choice for 48v to 12v converter would most likely be a Victron if I ever want to get one.
Larry

[boB]

Supposedly the Renogy Rover is MPPT so it should be similar to the Classic in this regard.

What that means is that when you over-power the input, the controller should raise the PV voltage above the PV array's maximum power point voltage where its output power reduces to the charge controller's maximum rating.

What can happen when a controller is severely over-powered is that this higher input voltage can make the charge controller heat up more than it normally would otherwise.

So, if you over-power one of these, and the charge controller doesn't get super hot, it should be OK.

boB

[Stone]

"Does Midnite Classic have this issue?  OR any other MPPT you know of?"

They're all going to have the same problem, the question is at what level.

The Renogy 40 is a cheap controller for small installations (I just bought one new for 100 bucks, not remotely in the same class as a classic 150)

At the end of the day, there's 3 parameters that matter here.

Input voltage
Input current
Output current.

My panels are in series parallel on my classic 150, because they rn more efficiently at higher voltages (series).

All in series gives me too high of an input voltage.

I upped to 24v, because a single classic can't charge 12v at the currents it makes with the panel configuration I have.

Renogy is weird about how they rate things, and they don't have a useful configuration utility.

I think in your position I would change your parallel panel setup and try it as series/parallel and see if you're going over the upper voltage limit.