High PV volts...CL200 or CL250?

[Jacotenente]

Hey guys - I have a long PV feeder cable run from my three e20 solar panels to my CL200 (purchased last year). The panels are e20/435 laminates:

Rated voltage: 72.9
Current: 5.97
VOC: 85.6
Short circuit V: 85.6
Short circuit A: 6.43

When operating in parallel, all three run about 66 volts (in parallel). When cold, they run at 69-70V. However, I would like to run them in series (Multiply x3  = 198v). I connected them up in series and the CL200 went into "HyperVOC".

Would a CL250 be able to handle the series voltage? I looking for better efficiency/power for the 125' cable run to the Classic. Wired in parallel, I have seen around 900w avg out of these panels (1,305 is the rated power). During "cloud edge" they have pushed out 1,400w.

Can Midnite exchange the CL200 for a CL250? Perhaps one of those "garage sale" deals? Would a Lite work?

Chris

[dgd]

With an OCV of 85.6v then in cold conditions the series voltage could push a Classic 250 into HyperVOC. So changing controller doesn't look useful.
Have you calculated the voltage drop over your 125 feet of cable from PVs to Classic?  If its too
high then either parallel cables or a lower gauge cable.
A better solution is to find a 4th identical panel then wire as 2S/2P

dgd

[ClassicCrazy]

Did you try the Midnite string calculator ?
It will let you know if your panel array will be okay  for the various Classic Controller models.

Larry

[CDN-VT]

A better solution is to find a 4th identical panel then wire as 2S/2P
Agreed if on tight budget

[Jacotenente]

Yep...agree 100%, 2S, 2P would work fine. I wired two in parallel and they worked with the CL200 w/o any issues. Around 135 volts while operating. I should have bought four when I had the chance. I will plug the numbers into the Sizing Chart and also check the voltage cable loss with that voltage drop online calculator. Right now, in parallel, all three are running and making power...but, I know efficiency will improve (and power) running them in series.