30A or 40A controller?
I’m going to mount 2 160w panels rated at 9.5 isc amps to feed 2 6v batteries…260ah. If I were to mount a 3rd panel I’m still under 30amps so a 30 amp controller should work fine….or should it. I’ve ...
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I don't have the panels yet and am still in the "sponge" mode so will try to soak up any info you have to offer.
Did your research include much about panel diodes
Do you normaly camp where its hot? Around the 100f mark? Or are you like me and chase the cooler weather? The panel i chose has a VMP of 17.40 volts and a IMP of 5.75 amps. A solar panel has voltage drop as temps rise, The trick is to let the volts drop a bit to closer to charging voltage. This will get the PWM controller the most efficient. A higher VMP will have a lower IMP and will deal with higher temps better but with less efficienty. Am I clear as mud?
Diodes can be used for blocking or bypassing. Blocking isnt used as much. Normaly it is used to keep the solar panel/s from drawing power at night. Most controllers take care of this task. Bypass diodes are in most panels. The number one reason they are there is to protect the manufactuers warranty. A 12 volt panel dosent require bypass diodes if used in parallel but panels used in series (the more the panels the bigger the problem) will cause a shaded panel section will "hot spot" (turn into a heater) This can degrade or destroy the panel section. As a side bonus a MPPT controller can continue charging at a lower rate as long as voltage stays above charging voltage. Clear as mud? :B
Did your research include much about panel diodes
Do you normaly camp where its hot? Around the 100f mark? Or are you like me and chase the cooler weather? The panel i chose has a VMP of 17.40 volts and a IMP of 5.75 amps. A solar panel has voltage drop as temps rise, The trick is to let the volts drop a bit to closer to charging voltage. This will get the PWM controller the most efficient. A higher VMP will have a lower IMP and will deal with higher temps better but with less efficienty. Am I clear as mud?
Diodes can be used for blocking or bypassing. Blocking isnt used as much. Normaly it is used to keep the solar panel/s from drawing power at night. Most controllers take care of this task. Bypass diodes are in most panels. The number one reason they are there is to protect the manufactuers warranty. A 12 volt panel dosent require bypass diodes if used in parallel but panels used in series (the more the panels the bigger the problem) will cause a shaded panel section will "hot spot" (turn into a heater) This can degrade or destroy the panel section. As a side bonus a MPPT controller can continue charging at a lower rate as long as voltage stays above charging voltage. Clear as mud? :B
