Power supply for in-line power controllers and two-terminal electronic thermostat employing same

Abstract From the Canadian patent

A two-terminal electronic thermostat connectable in series with an electrical heater and a source of AC power and selectively providing AC power to the electrical heater, and a power supply incorporated in the thermostat for providing DC power to the control circuitry of the thermostat includes a relay connectable in series with the electrical heater, a control circuit for selectively actuating the relay an ambient, temperature sensor and a potentiometer for setting a set point temperature. The power supply includes a current transformer having its primary winding connected in series with the relay and the electrical heater. The power supply also includes a first bridge rectifier circuit, a …