PWM and voltage
from this thread:
PWM just wastes any voltage higher than say 19-21V.
I think it’s worse than that. With PWM, the panel voltage is tied to battery voltage so it wastes anything higher than one’s highest battery voltage (usually Vabs).
Knock-on effects:
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underperforms in Bulk (12.2v is a long way from Vmp)
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performs better with lower-Vmp panels like poly and thin-film, rather than mono
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power output increases when Vabs and Vfloat setpoints are set higher ; they are sneaking up on Vm
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systems with PWM-charged banks will do better when the banks are cycled less deeply. Not [just] because there is less charging to do but because bank voltage will be higher –> panel voltage will be higher –> closer to Vmp –> more powah!