Controlling power delivered to a heating device occurs using a phase control, wherein the phase control includes changing a cut-off phase of an alternating current electrical signal delivered to the heating device. The power delivered to the heating device is increased from zero to an operational level using the phase control. The level of the power delivered to the heating device is maintained at the operational level using both the phase control and an integral half cycle control. The integral half cycle includes selectively removing a plurality of half cycles from the alternating current electrical signal delivered to the heating device.

A thyristor or triac control circuit includes a first capacitive element that is series-connected with a first diode between a first terminal and a second terminal intended to be coupled to a gate of the thyristor or triac. A second capacitive element is coupled between the second terminal and a third terminal intended to be connected to a conduction terminal of the thyristor or triac on the gate side of the thyristor or triac. A second diode is coupled between the third terminal and a node of connection of the first capacitive element and first diode.

A method of controlling at least one switching module having commutation cells which are associated with a regulating winding of a regulating transformer, the commutation cells including: a first and second switching element each having two thyristors in antiparallel connection.

A thyristor or triac control circuit includes a first capacitive element that is series-connected with a first diode between a first terminal and a second terminal intended to be coupled to a gate of the thyristor or triac. A second capacitive element is coupled between the second terminal and a third terminal intended to be connected to a conduction terminal of the thyristor or triac on the gate side of the thyristor or triac. A second diode is coupled between the third terminal and a node of connection of the first capacitive element and first diode.

The present disclosure provides a control circuit to control power to a load, a typically load being a heating element. The control circuit is preferably comprised of a switch, such as a TRIAC switch, to switch from a first state to a second state. An energy bank, such as a capacitor, is also provided, the energy bank to store energy to power a thermostat when the switch is in a non-conducting state. The control circuit is also comprised of a drive circuit to actuate the switch back and forth from the first state to the second state. The improved control circuit has been shown to have reduced conducted electromagnetic interference, which is advantageous to meet ever stricter government guidelines for circuitry conducted EMI.

A power supply device that allows individual control of an output voltage of a main transformer and an output voltage of a teaser transformer while utilizing output characteristics of the respective transformer when a Scott connected transformer has control equipment arranged on the input side thereof, including first control equipment arranged in one of two phases of the main transformer on the input side in order to control a voltage or a current and second control equipment arranged in one end of a primary coil of the teaser transformer on the input side in order to control a voltage or a current, the control equipment controlling an output voltage of the main transformer and an output voltage of the teaser transformer individually.

A method of controlling at least one switching module having commutation cells which are associated with a regulating winding of a regulating transformer, the commutation cells including: a first and second switching element each having two thyristors in antiparallel connection.

A phase controlled power regulation circuit is isolated from a line voltage and therefore overcomes some of the safety issues associated with currently available potentiometers. A phase controlled power regulation circuit employs a potentiometer that is electrically isolated from mains power. A transformer regulates the line voltage down to a reduced reference voltage that is used by the power regulation circuit. Any single point failure of a component within the power regulation circuit will not create unsafe condition. This greatly simplifies regulatory approval and opens new applications. Since the potentiometer is operated at low voltage, it may be remotely located from the circuits that handle the power with two conductors of class 2 wiring. Also, the potentiometer need not be of a panel mounted rotary or sliding type. It may be a potentiometer integrated circuit controllable from a microprocessor that enables complex regulation and/or sequencing control.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A dimmer is provided for controlling power to a load, the dimmer having a ground leakage power supply deriving power from a connection of the dimmer to ground. The power supply may be a switching-mode power supply that can be the sole or primary power supply to power operation of the dimmer, including operation of the controller.