B.Will wrote @Engineer_Dan From the wiring description of the dumb switch, that is a 3way switch. You need to use the HS210 to replace it. @B.Will Thanks for the response, but no, that is the only...

I'm baffled. I want to install a Kasa HS200 in place of a mechanical switch to operate a ceiling light. The existing installation has 4 wires - black, red, white and bare copper ground. The...