Calling on Solar Techies
I have been thinking of going solar for some time and decided to pull the plug. My wants are a 400 to 500 watt system. I have four 12 volt batteries with 340ah. I am not planning on changing b...
Forum Discussion
1L243,
MPPT runs about a 4% loss (i.e. 96% efficient). You may garner only about 10% more by moving to MPPT. Charging may start a little earlier in the morning, and last a bit longer during the day.
If you had room for a 6th panel, then you could do 2 strings of 3 panels, and that would save quite a bit on the cost of the MPPT controller.
MPPT works best when the batteries are low--as they approach fully charged the MPPT changes over to PWM mode.
MPPT may work some what better in low light conditions. But panels are a constant voltage type device.
My vote would be to stay the course with PWM and see if it meets your needs. If it doesn't, then it is a simple matter to rewire to series and get an MPPT controller.
I would do #10 wire from each panel to the combiner box (under the fridge vent), and then #6 or #8 to the input of the charge controller.
MPPT runs about a 4% loss (i.e. 96% efficient). You may garner only about 10% more by moving to MPPT. Charging may start a little earlier in the morning, and last a bit longer during the day.
If you had room for a 6th panel, then you could do 2 strings of 3 panels, and that would save quite a bit on the cost of the MPPT controller.
MPPT works best when the batteries are low--as they approach fully charged the MPPT changes over to PWM mode.
MPPT may work some what better in low light conditions. But panels are a constant voltage type device.
My vote would be to stay the course with PWM and see if it meets your needs. If it doesn't, then it is a simple matter to rewire to series and get an MPPT controller.
I would do #10 wire from each panel to the combiner box (under the fridge vent), and then #6 or #8 to the input of the charge controller.
