Pow switching device with enhanced programming

Abstract

A PCB motor controller comprises relays mounted on a PCB and interconnected to power traces in or on the PCB to receive incoming three-phase power and to output three-phase power to a motor. Control power traces in or on the PCB connect the relays to control circuitry, also mounted on the PCB. A power supply is mounted on the PCB and connected to the control circuitry to provide power for its operation and for switching of the relays. The relays are switched in accordance with a point-on-wave (POW) switching scheme, allowing for the use or relays and the PCB, which may not otherwise be suitable for motor control applications.

1 .- 20 . (canceled) 
     
     
         21 . A system comprising:
 a printed circuit board having three phase conductors for conveying incoming three phase power from a source and for outputting three phase power to a three-phase AC electric load;   control circuitry mounted on and electrically coupled to the printed circuit board and receiving power from a power supply; and   a set of relays mounted on and electrically coupled to respective phase conductors to receive the incoming power and to provide outgoing power when closed, the relays each having a direct current operator that receives power based on control signals from the control circuitry to switch in accordance with a point-on-wave switching scheme to open and close at desired times of an AC waveform of the incoming power and thereby complete current carrying paths from the source through the power conductors to the load; and   at least one sensor coupled to sense a parameter indicative of temperature or heating of at least one of the relays or a component thereof, and wherein the control circuitry is programmed to alter switching of at least one of the relays based upon the sensed parameter.   
     
     
         22 . The system of  claim 21 , wherein the relays comprise single pole relays. 
     
     
         23 . The system of  claim 22 , wherein the relays comprise three single pole relays. 
     
     
         24 . The system of  claim 21 , wherein the control circuitry is configured to switch the relays based upon an electrical zero crossing of at least one phase of incoming power. 
     
     
         25 . The system of  claim 21 , comprising a power supply disposed on the circuit board and coupled to the control circuitry via conductive traces on or in the circuit board. 
     
     
         26 . The system of  claim 21 , comprising driver circuits disposed on the circuit board and coupled to the control circuitry and to the relays, the driver circuits providing power for switching of the relays under the control of the control circuitry. 
     
     
         27 . The system of  claim 26 , wherein at least one of the driver circuits provides power to two of the relays. 
     
     
         28 . The system of  claim 27 , wherein a second driver circuit provides power to only one relay. 
     
     
         29 . A motor starter comprising:
 a printed circuit board having three phase conductors for conveying incoming three phase power from a source and for outputting three phase power to a three-phase AC electric motor;   control circuitry mounted on and electrically coupled to the printed circuit board and receiving power from a power supply; and   a set of relays mounted on and electrically coupled to respective phase conductors to receive the incoming power and to provide outgoing power when closed, the relays each having an operator that receives power based on control signals from the control circuitry to switch in accordance with a point-on-wave switching scheme to open and close at desired times of an AC waveform of the incoming power and thereby complete current carrying paths from the source through the power conductors to the motor; and   at least one sensor disposed on the circuit board and coupled to sense a parameter indicative of temperature or heating of at least one of the relays or a component thereof, and   wherein the control circuitry is programmed to alter switching of at least one of the relays based upon the sensed parameter.   
     
     
         30 . The motor starter of  claim 29 , comprising at least one sensor to sense current and/or voltage waveforms of the incoming power and to provide signals representative thereof to the control circuitry. 
     
     
         31 . The motor starter of  claim 30 , wherein the control circuitry is configured to determine zero crossing times of a waveform and to control switching of the relays based on the zero crossing times. 
     
     
         32 . The motor starter of  claim 29 , wherein the relays comprise single pole relays. 
     
     
         33 . The motor starter of  claim 32 , wherein the relays comprise three single pole relays. 
     
     
         34 . The motor starter of  claim 29 , wherein the control circuitry is configured to switch the relays based upon an electrical zero crossing of at least one phase of incoming power. 
     
     
         35 . The motor starter of  claim 29 , comprising a power supply disposed on the circuit board and coupled to the control circuitry via conductive traces on or in the circuit board. 
     
     
         36 . The motor starter of  claim 29 , comprising driver circuits disposed on the circuit board and coupled to the control circuitry and to the relays, the driver circuits providing power for switching of the relays under the control of the control circuitry. 
     
     
         37 . The motor starter of  claim 36 , wherein at least one of the driver circuits provides power to two of the relays. 
     
     
         38 . The motor starter of  claim 37 , wherein a second driver circuit provides power to only one relay. 
     
     
         39 . A motor starter comprising:
 a printed circuit board having three phase conductors for conveying incoming three phase power from a source and for outputting three phase power to a three-phase AC electric motor;   control circuitry mounted on and electrically coupled to the printed circuit board and receiving power from a power supply; and   a set of relays mounted on and electrically coupled to respective phase conductors to receive the incoming power and to provide outgoing power when closed, the relays each having an operator that receives power based on control signals from the control circuitry to switch in accordance with a point-on-wave switching scheme to open and close at desired times of an AC waveform of the incoming power and thereby complete current carrying paths from the source through the power conductors to the motor; and   a plurality of sensors disposed on the circuit board and coupled to sense a parameter indicative of temperature or heating of relays, and wherein the control circuitry is programmed to alter switching of the relays based upon the sensed parameter.   
     
     
         40 . The motor starter of  claim 39 , comprising at least one sensor to sense current and/or voltage waveforms of the incoming power and to provide signals representative thereof to the control circuitry, wherein the control circuitry is configured to determine zero crossing times of a waveform and to control switching of the relays based on the zero crossing times.