Over panel risk?

[gray webber]

I got some coaching on over paneling from a few members. I’ll share.
Boiling it down::::
Never exceed the VOC rating and you must include the temperature variable. (Often about .3% per degree C from 20C to say -20C would be 40x.3% or 12% more.
Call the SCC manufacture and ask if it can handle over amps. Most can to 20-50% but a few say no.
I called and found the Midnite Classic would just clip over amps off up to 50% so I can over panel by watts about 50% but not volts!
It will only pass what it’s rated for.

Your Renogy 40? Volts control and call them on amps. You may be 3p-2s?
Just 2cents

 

[Joyridge]

Definitely got the message on the over voltage side of things! Fire = BAD! My panels have a VOC of 37.5, running two in series per string, so I should be well within the voltage limit of 100 volts for the controller.

I’m really kicking myself for not buying a slightly beefier controller… for another $50 this wouldn’t even be a question.

 

[Kornbread]

I got some coaching on over paneling from a few members. I’ll share.
Boiling it down::::
Never exceed the VOC rating and you must include the temperature variable. (Often about .3% per degree C from 20C to say -20C would be 40x.3% or 12% more.
Call the SCC manufacture and ask if it can handle over amps. Most can to 20-50% but a few say no.
I called and found the Midnite Classic would just clip over amps off up to 50% so I can over panel by watts about 50% but not volts!
It will only pass what it’s rated for.

Your Renogy 40? Volts control and call them on amps. You may be 3p-2s?
Just 2cents

Well ... IIRC, the midnite classic sort of does clip volts. They call it hypervoc. It just sits there until the volts drop enough to safely operate.

 

[gray webber]

you are right—-2s X 3p is about right for good volts.
250x6 is 1500watts so a call on that would help. Yup , to bad you did not get one size larger. Maybe get a small second SCC rather then wasting the watts you can get because your current controller may just throw the extra away. A 20ax100volt or 30a EPEver is not too pricy. Good backup also should one go down.
Just an option.

 

[gray webber]

Yes- you are right its called hyper Voc as you said but issue is—-no charging until volts drop. Unit protection but throw away of power. I’d much rather get 84 of the 106 amps from over paneling then zero because the volts turn off all charging.
I like the safety function but unless your in a sweet rarely needed spot for cold temp moments then I’ll take the amps. Just me.
In my case I could see over voltage shut down maybe 30 days a year during the most needed cold winter days. What I mean is, on paper I could 3s my panels but if cold then hyper Voc would stop the charge till warm up.
Maybe my logic is flawed but oh well.

 

[gray webber]

Got the panel mount done. It all works good from vert to 65degrees.
Had to add two torque tubes but all worked.
Next is wait till the snow melts and take it to camp site for set up.
It breaks down into 4 easy to handle and haul pieces.
Will hold panels 36” min off ground.
Hand crank for tilt.