A system for measuring soft starter current includes a current monitoring system having a controller and a current transfer device that includes a first solid state switching device. A first current sensor is coupled to the first solid state switching device and the controller to sense off-state current of the first solid state switching device. The controller is configured to determine an operational status of the first solid state switching device.

Light-dimming device includes: first and second terminals; switch including switching device connected between terminals; adjuster for varying conduction angle of switch; controller for controlling switch and power supply module for supplying power to controller. Controller includes zero-cross detection circuit for detecting zero-cross of AC voltage, control circuit for generating PWM signal of on-duty ratio corresponding to conduction angle from adjuster, and driver circuit for turning device on and off by PWM signal. Controller allows device to conduct and then turn off within variable period of time, from start of half cycle of AC voltage, shorter than half cycle. Circuit starts generation of pulse in PWM signal when prescribed period of time, shorter than variable period of time, from zero-cross of voltage elapses.

A power supply unit for use with thermostats or other like devices requiring power. A power supply unit may be designed to keep electromagnetic interference emissions at a minimum, particularly at a level that does not violate governmental regulations. A unit may be designed so that there is enough power for a triggering a switch at about a cross over point of a waveform of input power to the unit. Power for triggering may come from a storage source rather than line power to reduce emissions on the power line. Power for the storage source may be provided with power stealing. Power stealing may require switching transistors which can generate emissions. Gate signals to the transistors may be especially shaped to keep emissions from transistor switching at a minimum.

A power supply unit for use with thermostats or other like devices requiring power. A power supply unit may be designed to keep electromagnetic interference emissions at a minimum, particularly at a level that does not violate governmental regulations. A unit may be designed so that there is enough power for a triggering a switch at about a cross over point of a waveform of input power to the unit. Power for triggering may come from a storage source rather than line power to reduce emissions on the power line. Power for the storage source may be provided with power stealing. Power stealing may require switching transistors which can generate emissions. Gate signals to the transistors may be especially shaped to keep emissions from transistor switching at a minimum.

A static transfer switch is used for switching an output load from a first power source to a second power source. A first switching unit has a first pair of silicon controlled rectifiers (SCR). A second switching unit has a second pair of SCRs arranged in an anti-parallel configuration. The control circuit determines whether at least one of the SCRs is activated in accordance with the voltage between the gate and the cathode of the at least one SCR. If the voltage between the gate in the cathode is at least 150 mV, the control circuit indicates that the at least one of the SCR is activated.

A static transfer switch is used for switching an output load from a first power source to a second power source. A first switching unit has a first pair of silicon controlled rectifiers (SCR). A second switching unit has a second pair of SCRs arranged in an anti-parallel configuration. The control circuit determines whether at least one of the SCRs is activated in accordance with the voltage between the gate and the cathode of the at least one SCR. If the voltage between the gate in the cathode is at least 150 mV, the control circuit indicates that the at least one of the SCR is activated.

The present disclosure provides an electronic device for driving a switch. An example electronic device for driving a switch includes: a first d driving circuit of the switch referenced to the first terminal adapted receive an alternating potential, formed on a first substrate, and comprising a first diode whose cathode is connected to the first substrate; a second driving circuit referenced to the second terminal adapted to receive a reference potential, formed on a second substrate, and comprising a second diode whose cathode is connected to the second substrate; and an anode of the first diode is connected to the second driving circuit, and an anode of the second diode is connected to the first driving circuit.

The present disclosure provides an electronic device for driving a switch. An example electronic device for driving a switch includes: a first d driving circuit of the switch referenced to the first terminal adapted receive an alternating potential, formed on a first substrate, and comprising a first diode whose cathode is connected to the first substrate; a second driving circuit referenced to the second terminal adapted to receive a reference potential, formed on a second substrate, and comprising a second diode whose cathode is connected to the second substrate; and an anode of the first diode is connected to the second driving circuit, and an anode of the second diode is connected to the first driving circuit.