MPPT controller and DC load output

[Bsmiffffy]

I am about to replace my old 100w solar panel and old controller with a 400w panel and mppt controller. My question is can I use the DC load from my new mppt controller to feed into my old pwm controller and then into a second battery. Will both batteries charge simultaneously.

 

[johnb2713]

The simple answer is no.

A PWM controller controls the rate of charge by PWM (Pulse Width Modulation), essentially it switches it's output for a short space of time and then off again, often 1000 times per second. The longer the 'on' time is the more power it's transferring. To charge two batteries simultaneously they either need to be connected in parallel or a dual output MPPT controller used.