I received a call the other day from an INSTEON user who had made a sizable investment in INSTEON automation devices and had started the installation process. He had installed a KeypadLinc in a central location to control lighting circuits throughout his home. He then installed a ToggleLinc switch in a remote location and was attempting to link it to one of the KeypadLinc buttons. He had repeated the process numerous times, following the manufacturer's instructions "to the letter" with no success. Why wasn't anything working?
Linking problems and unreliable operation can most often be traced to a defective plug-in battery charger/power supply somewhere in the home. These devices, used to charge cell phones, laptop computers, tablets, and rechargeable batteries as well as power small electronic devices like cable TV boxes, modems, and routers have been known to generate high levels of power line noise that can prevent communication between INSTEON power line devices. The offending battery charger/power supply may be working perfectly for its intended purpose, but a defective component or poor design may still be causing a previously unknown high noise levels on the power line.
He unplugged his cell phone charger and everything started working. Problem solved!
To permanently resolve the issue (and continue to use his cell phone) we recommend replacing the defective charger. If the charger cannot be easily replaced, a filter can be added to isolate the noise from the power line.
See my News blog post titled "What makes INSTEON more reliable than other automation technologies".