Watts needed
I have read where folks suggest any where from 1 to 2 watts of solar per ah of battery. My question, is this based on battery rating (ie 215 AH) or is it based on useable amp hours(105)? All reply...
Forum Discussion
"I am not so sure of your figures. I just finished an upgrade. In my initial testing I was getting 714 watts from an array that had a max of 720 watts.
Using your method, I should only be able to get 590 watts."
To sort this out, need your volt and amp measurements at the input and output terminals of the solar controller while it is in Bulk (which is when it is in MPPT)
My example also assumes the panel is aimed at a high sun with clear sky. Be even fewer amps output with panel flat on roof, eg.
It is hard to get the input amps to the controller, so if no clamp ammeter just see what the input voltage is. It should be whatever the controller decides is Vmp at the time.
Using your method, I should only be able to get 590 watts."
To sort this out, need your volt and amp measurements at the input and output terminals of the solar controller while it is in Bulk (which is when it is in MPPT)
My example also assumes the panel is aimed at a high sun with clear sky. Be even fewer amps output with panel flat on roof, eg.
It is hard to get the input amps to the controller, so if no clamp ammeter just see what the input voltage is. It should be whatever the controller decides is Vmp at the time.
