Or maybe the example attached? One of the 3 options should work?
ignore where the picture says 24VDC, they sell a 5VDC option.

would this be able to trigger a relay for a small fan with a 3-5 amp max draw? 3-5 amp is current for fan, for relay coil it will be probably 50mA which is 100% fine. You need to use relay with 5V coil. would a 6V relay work? it still should provide enough voltage to switch it on at 70-75% https://...

would this be able to trigger a relay for a small fan with a 3-5 amp max draw? 3-5 amp is current for fan, for relay coil it will be probably 50mA which is 100% fine. You need to use relay with 5V coil. would a 6V relay work? it still should provide enough voltage to switch it on at 70-75% https://...

would this be able to trigger a relay for a small fan with a 3-5 amp max draw?