Seems like a good time to post this question, on the heels of Mex's post about the import market...I need a 60a MPPT controller. Debating between the Morningstar Tristar 60, or the MidNite Solar Classic 250.I'm attracted to the Tristar because it's fanless. It will be in the basement, so it's not the noise, just the fact that fans are one more thing to go wrong.Prices I have seen peg the Classic at a significant premium to the Tristar. Other than a "Made in USA" label, does MidNite offer substantial benefits that the MS does not?Feel free to suggest another brand as well.Thanks for your input.

What's your PV voltage and your battery voltage?

From my lazy point of view.I like being able to see what controller is doing. Without opening a laptop or installing a battery monitor. Tristar offers an optional (cr.appy) remote display, Midnite - none. OTH, I see on the Midnite some on-board control interface (those arrow buttons), but in the basement it won't be as convenient, depends where you put it. Tristar won't let you control anything without opening the laptop again (or the controller body).Can't comment on firmware and algorithm of either one.Are you sure you need 60A?

Morningstar is pretty much three max 24v panels in series. 150 max VocMidNite 250 will be up to five panels in series. 250 max VocWhat are you going to run? Put your panels in the string calculator.

This has been discussed extensively, with MPPT you can oversize the array as long as you stay within VOC. Voltage-wise, TS 60 would be four 24 panels but peak amps "might" get clipped at times. Not very often at sea level with flat panels.

smkettner wrote:What are you going to run? From that other thread I recall 2*265W or 4*140W. With possible addition of another 24V or a pair of 12V later. This comes to 45-50A at 100-something V (after that extension). Sounds like Morningstar 45 :). Or some other 45-50A MPPT.

MPPT Controller Selection | Good Sam Community

41 Replies

Almot
Explorer III
Mar 05, 2016
SMK - 2*265W flat would be towards the higher end of 45A controller, but not unreasonable.

3*265W flat would require 60A controller. With 45A it might still work in Ca winter, flat, at sea level, but I wouldn't want to push it that far.
time2roll
Nomad
Mar 05, 2016
I was just speaking to the voltage limit.
Mounted flat you can push the wattage a bit extra. MPPT will self limit amps to stay within rating.
3*265 would be toward the high end of reasonable for 45 amps IMO. (mounted flat)
Almot
Explorer III
Mar 05, 2016
smkettner wrote:
I would be looking at the Midnite 200 so that four large panels would go in series. Voc on these panels at ~37 volts really limits the 150s to three series panels and then you will not get 60 amps.

Did they specify the panels wattage and number? Last time it was 2*265, or alternatively 4*140.
2*265 is well within 45A and 100V.
3*265 would require 60A and 150V.
diveman52
Explorer
Mar 04, 2016
I went with the Midnight classic 150 same as 250 just limited to 150 volt input.
I does have a remote included. The Control are easily removed (it's designed for remote mounting.)and used as a remote with the addition of some 6 wire telephone cable.
mchero
Explorer
Mar 04, 2016
I see you guys are talking about the Midnight Solar controllers. If you go to the Midnight Solar forum, hosted by Midnight solar they are selling off some refurb units. Might be worth a look.

I'm running a Classic 200 light & am very happy with it.

http://kb1uas.com/mnsforum/index.php?PHPSESSID=df9cc6710d0f78387c98519b80a3c236&board=58.0
Almot
Explorer III
Mar 04, 2016
wrong post - deleted
brulaz
Explorer
Mar 04, 2016
Ductape wrote:
Almot, the benefit of reading the shunt is the controller now knows how much current is output from the controller (e.g. 6 amps) and how much is accepted by the battery, perhaps only 3 with the other 3 going to house loads.
...

That does seem like a nice feature.

Currently my Rogue only knows the current it's putting out, and so will stay in "absorb" mode when other draws are present, normally until the timer forces it off. Unfortunately the timer appears to have died in mine.
Ductape
Explorer
Mar 04, 2016
Almot, the benefit of reading the shunt is the controller now knows how much current is output from the controller (e.g. 6 amps) and how much is accepted by the battery, perhaps only 3 with the other 3 going to house loads.

Current into the battery determines "full" on AGM. I don't mind giving the LifeLines exactly what the factory recommends. I want them to live a long and happy life.
CA_Traveler
Explorer III
Mar 04, 2016
smkettner wrote:
I would be looking at the Midnite 200 so that four large panels would go in series. Voc on these panels at ~37 volts really limits the 150s to three series panels and then you will not get 60 amps.
Good input. I can't add another 250W panel to my 3x 250W series panels without going series/parallel due to the MPPT 60 150V limitation.

Series/parallel panels have shadow limitations (like all parallel panels) that do not appeal to me. But it's also not a huge concern for me.
time2roll
Nomad
Mar 04, 2016
I would be looking at the Midnite 200 so that four large panels would go in series. Voc on these panels at ~37 volts really limits the 150s to three series panels and then you will not get 60 amps.

Forum Discussion

MPPT Controller Selection

41 Replies

About Technical Issues

Related Content

Sway Control

MPPT Controllers

Renogy 20A MPPT Controller- electrical/amp question

Grounding an MPPT controller

MPPT solar charge controller with 12v panels...