I plan on using a Steca PR1515 for an upcoming application. We're using a 60-cell module, which has roughly 8A current and 30V Vmp. This charge controller is rated for 15A of current and less than 47V.
I'm concerned that when the charge controller decreases the input voltage to 12V nominal, it will increase the current beyond the charge controller's capacity. Is my concern well-founded?
Submitted
12 years 2 months ago
Comments
tbone,
The charge controller won't decrease the module voltage in the case of PWM charging. The battery will set the system voltage - as the module voltage is reduced, so is the overall power output of the module. I would go into the math, but one of our forum users, leventbas, has already posted a useful illustration and compared the PWM technology to MPPT, or Maximum Power Point tracking.
Link: https://www.greentechrenewables.com/node/8639