Originally Posted by
randyc
The instructions assume standard 3-way wiring where the power comes in on one end of the circuit and goes out to the light (switch leg) on the other. There is a technique where you have power and the switch leg are on the same end. This usually involves a white wire connected to the 3-way.
The Caseta switch will turn on/off whenever there is a change in voltage on the blue wire. You are using the 3-way as a contactor to add or remove the voltage. I would install the Caseta switch so it works by itself, then move to the other end and set up the 3-way.