Experiment with constant DC source to both MPPT and PWM cont

[edgeau]

An interesting experiment, running a controlled constant DC supply to both an MPPT and a PWM charger solar input. I wondered if a cheap second hand DC to DC unit that is not lithium compatible could go to my MPPT solar input to get around it. Spoiler alert – no but it would for a PWM.

I have a nifty hobby power supply where I can set constant voltage and max current. So I set it for 14v and 3A as that is a common DC2DC output and fed it to the solar input on my MPPT charger. No action so I stepped up the voltage by 0.1 volt incriminates. Turns out I needed 15.3 on the power supply for the charger to go. The charger registered it as 15 probably voltage drop across the watt meter. Some photos showing the power supply, watt meter I had between and the controller.








So that saved me buying a DC 2 DC unit as they don’t do 15V.

I also have a PWM that came with my Solar blanket so out of curiosity I tried the same experiment on that.
It worked happily with a 14V input and put 13.5 out to the old AGM battery I have with it.



Sent from my Pixel 6 using Tapatalk