In a traditional lighting control panel, you have low voltage switching devices (relays or switch grade circuit breakers) combined with a master control or building automation system.  The master control system is the communication channel that provides the instruction to the switching device to open or close the circuit.  Most are simple scheduling systems, but often they include occupancy or optical sensors that can automate the on/off commands sent out by the control system.  The key point is that the switching devices require direction from a separate control system and cannot provide information back to the master automation system as it is a one-way communication channel.  These panels are still in the marketplace and are typically inexpensive; however you also have to add the cost of the master control system to determine your complete project costs.

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