ANOTHER D*** Solar Question!!!!
Just upgraded trailer to a new, much larger trailer (Timber Ridge 280RKS) which has a "huge" 10W Zamp solar panel. The panel is wired directly to the battery through a master switch and 30A breaker. ...
Forum Discussion
BFL13 wrote:
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Some confusion here I think.
With PWM the panel's Vmp has no meaning. That is only for MPPT and then only when it is in MPPT mode (during controller "Bulk")
With the PWM, panel voltage will be the same as battery voltage plus line loss.
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Yep sure is, you need to know Vmp when adding panels for either PWM or MPPT CC's.
During bulk charge input to the PWM CC will be about battery voltage; this will increase until the battery charge reaches a point where the PWM can hold 14.5 volts on it's output to the battery. At that point the input voltage to the PWM CC starts to rise towards Vmp. Once you reach ~ 80% charge the CC then switches to absorb and output voltage will be 14.9 volts or at least that is what my Morningstar PWM's are programmed for.
Prior to about 10 am a PWM controller just passes panel output to the battery.
Vmp along with Imp is how you determine panel wattage. So yes Vmp is not meaningless.
