It would be good to put a dc controller in between panel and dc fan.
How to connect solar panel to fan.
Just connect the panel to the fan no diode no batterys you probably have attic exhaust fans if you bought from a solar dealer motors are not sensitive to the voltage if its higher its just spins a bit faster.
How to power fan directly from solar panel.
Secure the temperature controller within the electrical box and set a temperature that will activate the fan.
Two holes were drilled in the back of the van right above the back most roof beam to feed the solar cable into the van.
Just treat the leads of the panel like those of a battery red and black just connect those to the fan if you match color for color no problem.
Then i cut the 30 foot mc4 cable in half and attached each y adapter to it s mating end of the cable halves.
With all the solar battery buzz you might be wondering if they re essential solar equipment.
In order to run a solar fan directly from solar panel without battery you need to select whole system carefully.
Use a wire nut to secure all together.
A fan having 12vdc and 25 watt need a panel of 12vdc and 30watt.