The device includes at least the following components: a heating resistor intended for heating a component to be regenerated; a current source; a thermistor connected to the current source and thermally coupled to the heating resistor, the thermistor, through which the current flows, having a voltage Vtemp across its terminals, which voltage reflects the temperature of the heating resistor; an error amplifier, which amplifies the difference between the voltage Vset and the voltage Vtemp and delivers a voltage Vctrl that corresponds to the amplified difference; a switch, which switches the current flowing through the heating resistor; an oscillator, which delivers a voltage Vosc formed with a modulated duty cycle, the duty cycle of the pulses of the voltage Vosc being dependent on the voltage Vctrl, the pulses controlling the opening of the switch.

A power harvesting system employs a saturable core transformer having two primary windings and at least one secondary winding. One of the primary windings is a high impedance winding, and the other primary winding is a low impedance winding. The two primary windings are connected with the load (motor). The secondary winding provides power to the circuit components of a replacement electronic thermostat. Relay contacts connects A/C power to either the high impedance primary winding or to the low impedance primary winding. When the relay is de-energized, A/C power is applied to the high impedance winding so that a relatively small amount of current flows through both the high impedance winding. This current is low enough that it does not energize the motor but is sufficient to generate the required voltage to transfer power to the secondary winding and is used to power the electronic thermostat. When the relay is energized, A/C power is applied directly to the low impedance primary winding, energizing the motor. At the beginning of each A/C cycle, the current through the low impedance winding builds up rapidly until the core saturates. The result is that a short pulse is generated in the secondary on both the positive and negative A/C cycle. This pulse has an amplitude determined by the turns ratio of the low impedance winding to the secondary winding and is used to power the electronic thermostat. After the core saturates, the impedance of the low impedance winding is only the resistance of the wire of the winding which is very small and results in negligible impact on the motor operation and also results in very low power dissipation.

A method for manufacturing a composite material, a sensor element or an active component of a sensor element. The sensor element is applied in a field device of automation technology. At least two materials with different physical and chemical properties are predetermined depending on a functionality of the sensor element or the active component of the sensor element. An outer shape, into which the at least two materials should be formed, is predetermined. The outer shape is divided into a plurality of virtual spatial regions, wherein in each virtual spatial region the material distribution of the at least two materials occurs homogeneously and periodically according to predetermined rules corresponding to a microstructure. The predetermined rules are ascertained via a computer supported method depending on the predetermined functionality of the sensor element or the active component of the sensor element, wherein digital data, which describe the ascertained distribution of the at least two materials, are transferred to at least one 3D printer. As a printed product the sensor element or the active component of the sensor element is created by the 3D printer based on the digital data.

The invention relates to a method for manufacturing a sensor element or an active component of a sensor element. The sensor element is applied in a field device of automation technology. The method comprises the following method steps: predetermining at least two materials with different physical and chemical properties depending on a functionality of the sensor element or the active component of the sensor element; predetermining an outer shape, into which the at least two materials should be formed, the outer shape being divided into a plurality of virtual spatial regions, wherein in each virtual spatial region the material distribution of the at least two materials occurs homogeneously and periodically according to predetermined rules corresponding to a microstructure. The method also includes steps of ascertaining the predetermined rules via a computer supported method depending on the predetermined functionality of the sensor element or the active component of the sensor element.

The present disclosure is directed to an optical device including at least one temperature-dependent tunable element for controlling a wavelength of an optical signal, a first temperature control circuit for controlling a temperature of a first region of the optical device; and a second temperature control circuit for controlling a temperature of a second region of the optical device. The second region may include a portion of the first region. The second region may be smaller than the first region. The tunable element may be positioned in the second region such that a temperature of the tunable element is controlled based on the second temperature control circuit controlling the temperature of the second region. The tunable element may be one of (i) a laser for transmitting an outgoing optical signal and (ii) an optical filter coupled to a photodetector for receiving an incoming optical signal.

A fluid heater includes a heating circuit, a temperature monitoring circuit, a controller, and an overheat sensing element. The controller is disposed in a control unit and is in circuit communication with a temperature gauge and a power supply switch, the controller being configured to operate the power supply switch in response to feedback from the temperature gauge to maintain the heater at a setpoint temperature. The overheat sensing element is disposed in a heater housing proximate to a thermal fuse and is in circuit communication with the controller to provide an indication to the controller when the overheat sensing element reaches an overheat temperature lower than the critical temperature. The controller is configured to operate the power supply switch to reduce or shut off power to the heating element in response to receiving the indication that the overheat sensing element has reached the overheat temperature.

A temperature limiting device for a thermal system includes a modular unit that is configured to connect to a two-wire heater of the thermal system. More particularly, the modular unit includes a heater interface configured to connect to a two-wire heater of the thermal system, a power interface configured to connect to a power source to receive power; and a controller including a sensor circuit. The sensor circuit is configured to measure an electrical characteristic of the two-wire heater, which includes voltage, current, or a combination thereof. The controller is configured to calculate a temperature of the thermal system based on the measured electrical characteristic and determine whether the temperature is greater than a temperature setpoint.

The present disclosure is directed to an optical device including at least one temperature-dependent tunable element for controlling a wavelength of an optical signal, a first temperature control circuit for controlling a temperature of a first region of the optical device; and a second temperature control circuit for controlling a temperature of a second region of the optical device. The second region may include a portion of the first region. The second region may be smaller than the first region. The tunable element may be positioned in the second region such that a temperature of the tunable element is controlled based on the second temperature control circuit controlling the temperature of the second region. The tunable element may be one of (i) a laser for transmitting an outgoing optical signal and (ii) an optical filter coupled to a photodetector for receiving an incoming optical signal.

The device includes at least the following components: a heating resistor intended for heating a component to be regenerated; a current source; a thermistor connected to the current source and thermally coupled to the heating resistor, the thermistor, through which the current flows, having a voltage Vtemp across its terminals, which voltage reflects the temperature of the heating resistor; an error amplifier, which amplifies the difference between the voltage Vset and the voltage Vtemp and delivers a voltage Vctrl that corresponds to the amplified difference; a switch, which switches the current flowing through the heating resistor; an oscillator, which delivers a voltage Vosc formed with a modulated duty cycle, the duty cycle of the pulses of the voltage Vosc being dependent on the voltage Vctrl, the pulses controlling the opening of the switch.

The present disclosure is directed to an optical device including at least one temperature-dependent tunable element for controlling a wavelength of an optical signal, a first temperature control circuit for controlling a temperature of a first region of the optical device; and a second temperature control circuit for controlling a temperature of a second region of the optical device. The second region may include a portion of the first region. The second region may be smaller than the first region. The tunable element may be positioned in the second region such that a temperature of the tunable element is controlled based on the second temperature control circuit controlling the temperature of the second region. The tunable element may be one of (i) a laser for transmitting an outgoing optical signal and (ii) an optical filter coupled to a photodetector for receiving an incoming optical signal.