Forum Discussion
BFL13
May 01, 2015Explorer II
The input voltage limit for a controller is the array total panel Voc (NOT Vmp), which must be corrected for actual conditions where the panel Voc might be higher than its rating, such as in cold temps.
When doing calculations for amperage using a PWM controller, you use the panel's Isc as its expected max amps when pointed at a high sun.
Vmp and Imp have absolutely no meaning with PWM!!! Those are strictly for MPPT calculations (Vmp x Imp = input watts to the MPPT controller when it is in "MPPT mode" which is "Bulk" in MPPT language)
When doing calculations for amperage using a PWM controller, you use the panel's Isc as its expected max amps when pointed at a high sun.
Vmp and Imp have absolutely no meaning with PWM!!! Those are strictly for MPPT calculations (Vmp x Imp = input watts to the MPPT controller when it is in "MPPT mode" which is "Bulk" in MPPT language)
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