I have a pair of USB powered fans. I currently have them connected to a Raspberry Pi 3b+ via one of the USB-A connectors, drawing power from the pi.
I have two cron jobs set on the pi - one that disables power to the USB controller every even minute, and then one that re-enables power every odd minute. This effectively turns the RPi into a fan controller. This allows the fans to run in my greenhouse to cycle air, but doesn't keep them running so much that they dry everything out.
I am using
uhubctl as described in one of the answers to this question:
My concern is, I am basically adding and removing power to the USB controller every minute of every day. Will this eventually cause damage to the USB controller? Can it cause damage over time?