Review on 🌡 WH8040 1%~99% RH HM-40 Type Digital Air Humidity Control Controller 110V by Brian Price

I am always amazed at what modern global manufacturing can do and this is one example. I made a lot of electronic circuits out of circuits as a kid (thanks Forrest Mims III!) and now I find I don't need to do that anymore because even Revain has circuits ready made for very little money. . Considering that this unit probably has some sort of microprocessor in it, is well made, has good screw terminals, does its job perfectly and is easily calibrated, I'm very impressed with its price. Dehumidifier (regular home, no HVAC installation) at my shop with digital control panel. I'm not sure how old it is, probably at least 8 years old, but the button to decrease the humidity setting stopped working a while ago and I had my doubts as to how accurate the unit had become. I connected this controller to it and now I have an adjustable humidity controller again. like a thermistor in the sense that its resistance decreases as humidity increases. I shorted the terminals and the dehumidifier display showed "Hi" which happens when the reading exceeds 90% so I was right which was handy. I put a dab of solder on the board to connect the sensor pins together. Now I had a dehumidifier that was always on. To set it I ran the wires from the bucket/water level switch to a relay connection on the humidistat. Now when the controller says the humidity is too high, it's essentially telling the dehumidifier (which thinks it needs to run 100% of the time, but not if the bucket isn't there) that the bucket is just about deployed became it can run. . To avoid that annoying "no bucket" beeping from the dehumidifier, I just ripped the piezo speaker off the circuit board.