Confusing the MPPT controller
Here I go with my ignorant self again, seeing something and thinking I can figure it out. ;) When I first got my original panels I talked to quite a few people including Mark at Rogue saying to run...
Forum Discussion
Generally I feel I have been lucky to have had as many different panels as I have and be able to run the odd ball test. You can see do this or that but not often why. Most people don't use a program to see the second by second operation of the controller either.
To the controllers credit, even in it's confusion it was able to deliver the total amps I would expect out of a pair of the weaker panel. Push come to shove the pair still deliver more than either panel alone in bright light. In low light it's better to run the poly by itself.
Looking at a log of the 220w and 230w in parallel earlier this year I can see the same rise and fall of the array voltage and current. This time the pair did produce close to the expected 27a.
So the controller will function and the output should be predictable if not perfect. Matching panels will always be the best choice.
Now if I had to run those two panels and found that running them together was bad for a single controller, I would run them with a pair of Eco-W just as I will run the 230w as a portable if needed. The Isc exceeds ratings here at altitude but that's nothing compared to what a MPPT controller can do with the excess voltage.
To the controllers credit, even in it's confusion it was able to deliver the total amps I would expect out of a pair of the weaker panel. Push come to shove the pair still deliver more than either panel alone in bright light. In low light it's better to run the poly by itself.
Looking at a log of the 220w and 230w in parallel earlier this year I can see the same rise and fall of the array voltage and current. This time the pair did produce close to the expected 27a.
So the controller will function and the output should be predictable if not perfect. Matching panels will always be the best choice.
Now if I had to run those two panels and found that running them together was bad for a single controller, I would run them with a pair of Eco-W just as I will run the 230w as a portable if needed. The Isc exceeds ratings here at altitude but that's nothing compared to what a MPPT controller can do with the excess voltage.
