by Paul B pbibm|
If you have insteon you will most likely need at leasat one of these
Like all technologies that use the powerline, Insteon needs a way for its signals to get from one phase to the other.
One way is to use the Insteon PLM as your server interface, and use one of these access points as a bridge. The PLM is an access point in addition to being a PLM. I put my plm and an access point on opposite phases on outlets near my electrical panel so that the signal is bridged at the center of the power network.
My old house needed a couple more of these access points too, which I added over time two specific long circuits get things perfect.