Review on Monitor Controller Function Remote Sensor by Michael Hudson

Pros: Works as advertised Easy connection to controller Cons: The instructions are written to help you get everything hooked up, but the instructions on how to actually set it up to your liking are vague at best. You need to understand two words: ZONE and CENTER.Center = where you want ppm. Probably around 1200 ppm for plants. Zone = how far you want to be from the central target. If you set the center to 1200 and the zone to 200, it will turn on at 1000ppm and off at 1400ppm. The factory default is 400, which is quite different from the target center of 1200.