Lowest OCV An MPPT Is "Worth It"?
There has to be some experience here on this forum to share. When I look at the MPPT manufacturer's data specs, the incredo-hyperbole gives me diarrhea.
Forum Discussion
I'd better explain what I'm up to, here......
Mexican ADUANA, the Customs folks at the border lick their chops when they chance across a solar panel the size of half a ping-pong table. Residential grade high voltage polycrystalline panels. Yet these panels are heavy as hell, cumbersome, and tend to complain when a 20 lb coconut drops 15 feet on them. Yet again, these panels, watt for watt, are considerably less expensive per watt than <21 OCV panels.
That being said, there is a lot of space between say 14.8 volts and lower OCV "optimum working voltage" of say 17.5 VDC. Got it? Damned near three volts. Is the excess supposed to run around in circles and yell "Help! Help!"?
I guess I have to design my own controller. A PWM that I can adjust the maximum time at absorbsion limit before it defaults to float. A controller that can pass MAXIMUM available panel amps at float to remain in float until battery voltage sags to a point where absorbsion is appropriate.
Where are they getting these idiots that design controllers? Companies like Outback have genuine engineers, but I am not going to have a 7 piece Oneida sterling silver place setting administering a Chinet plate. I do not have that kind of money.
Mexican ADUANA, the Customs folks at the border lick their chops when they chance across a solar panel the size of half a ping-pong table. Residential grade high voltage polycrystalline panels. Yet these panels are heavy as hell, cumbersome, and tend to complain when a 20 lb coconut drops 15 feet on them. Yet again, these panels, watt for watt, are considerably less expensive per watt than <21 OCV panels.
That being said, there is a lot of space between say 14.8 volts and lower OCV "optimum working voltage" of say 17.5 VDC. Got it? Damned near three volts. Is the excess supposed to run around in circles and yell "Help! Help!"?
I guess I have to design my own controller. A PWM that I can adjust the maximum time at absorbsion limit before it defaults to float. A controller that can pass MAXIMUM available panel amps at float to remain in float until battery voltage sags to a point where absorbsion is appropriate.
Where are they getting these idiots that design controllers? Companies like Outback have genuine engineers, but I am not going to have a 7 piece Oneida sterling silver place setting administering a Chinet plate. I do not have that kind of money.
