I am working on a senior design project and just wanted to ensure the following charge configuration would work. I have a 12V solar panel that I plan to run its' output to TWO separate PWM solar charge controllers. Despite the vehicle running off a a 24V system, I would like to charge the batteries separately. I think that I need some sort of changeover relay to alternately charge the two 12V batteries .I think I need some control for the relay . Could I use just one PWM charge controller if I employ the relay ? Do you think that my concept will be cheaper than 2 solar arrays and 2 PWM controllers? Just wanted some input from those who have more experience than me with solar energy. Thanks for the help and sorry for the rotated picture!
You can do that only if the outputs of the solar charge controllers are fully isolated from the inputs.
If the controller output grounds are directly connected to the input grounds (as is likely), you would be shorting the "bottom" battery through the ground leads.
best answer is probably to use a charge cintroller that outputs 24V from a 12V panel and charge the two batteries in series.
lead acid boost charge controller