MPPT Controller Selection
Seems like a good time to post this question, on the heels of Mex's post about the import market... I need a 60a MPPT controller. Debating between the Morningstar Tristar 60, or the MidNite Solar ...
Forum Discussion
Ductape wrote:
Tristar really does not explain how they terminate to float. The language is "The transition to float is based on the previous 24 hour history. Factors include the battery voltage, the state of charge the night before, the battery type, and the PWM duty cycle and stability of the duty cycle."
Tristar Manual
Your link is to PWM version. Here is TS MPPT.
As I recall, Tristar MPPT terminates Absorb and transitions to Float based on voltage at the beginning of charging. The default time is 120 minutes and will be increased by 30 minutes if battery was discharged below 12.5V.
I prefer current-based termination. This is what my Rogue MPPT 30 does, transitioning to Float when current drops to pre-set value. Adjustable timer will override the transition if needed. 30A is enough for up to 500W with 12V bank or 1000W with 24V bank. Made in the US. I was lucky to get it while they were still making it. Paid $350.
You don't need more than 15-20 days history unless it's left in storage for 5-6 months (and even then you don't need more than 180 days).
