Auto detection of type of device using single wire two-way communication

A dimmer switch system for dimming a load, the dimmer switch system comprising:

• a master dimmer structured to be electrically connected to a power source and the load and to control dimming of the load by regulating power provided from the power source to the load;
• and
• at least one accessory dimmer structured to be electrically connected to the master dimmer via a traveler conductor,
• wherein the master dimmer is structured to generate a first control signal on the traveler conductor to indicate a type of the master dimmer,
• wherein the at least one accessory dimmer is structured to selectively enable or disable one or more functions of the at least one accessory dimmer based on the type of the master dimmer,
• wherein the at least one accessory dimmer is structured to generate a second control signal on the traveler conductor,
• wherein the master dimmer is structured to generate the first control signal on the traveler conductor in response to the second control signal,
• wherein the master dimmer is structured to generate the first control signal on the traveler conductor during one of a positive or negative half-cycle of power from the power source, and
• wherein the at least one accessory dimmer is structured to generate the second control signal on the traveler conductor during the other of the positive or negative half-cycle of power from the power source.

A method of detecting a type of a dimmer for a dimmer switch system, the method comprising:

• providing a master dimmer electrically connected to a power source and a load and controlling dimming of the load by regulating power provided from the power source to the load with the master dimmer;
• providing at least one accessory dimmer electrically connected to the master dimmer via a traveler conductor;
• generating a first control signal on the traveler conductor with the master dimmer to indicate a type of the master dimmer;
• selectively enabling or disabling one or more functions of the at least one accessory dimmer based on the type of the master dimmer;
• and
• generating the first control signal at a selected predetermined time after a zero crossing in one of the positive or negative half-cycle of power from the power source,
• wherein the selected predetermined time corresponds to the type of the master dimmer.

A dimmer switch system for dimming a load, the dimmer switch system comprising:

• a master dimmer structured to be electrically connected to a power source and the load and to control dimming of the load by regulating power provided from the power source to the load;
• and
• a number of accessory devices connected to the master dimmer via a traveler conductor,
• wherein the number of accessory devices are of an accessory functionality type,
• wherein the master dimmer is structured to monitor the traveler conductor and to determine the accessory functionality type of at least one accessory device based on said monitoring,
• wherein, the monitoring of the traveler conductor occurs during one of a positive or negative half-cycle of power from the power source, and
• wherein the master dimmer is structured to determine that the number of accessory devices includes one device that is a dimmer when power flows to the traveler conductor for a non-zero fraction of the half-cycle of power during the monitoring.