Abstract:
A method and system for supplying power to a portable electronic device includes supplying current from one or more fuel cells to a DC-DC converter and regulating a current limit of the DC-DC converter as a function of a measured temperature of at least one of the power supply system and the portable electronic device. The current limit can vary as an inverse function of the measured temperature. The current limit can be an input current limit of the DC-DC converter or an output current limit of the DC-DC converter. Current produced by the one or more fuel cells can decrease proportionally to a decrease of the current limit of the DC-DC converter, reducing the heat produced by the one or more fuel cells and thereby reducing the measured temperature. A temperature sensor can be located on or near the one or more fuel cells. A temperature sensor can be located on an internal housing of the portable electronic device.
Abstract:
Methods and apparatus to detect leakage current in a resistance temperature detector are disclosed. An example method includes providing a resistance temperature detector circuit with a first resistance circuit and a second resistance circuit, measuring a first voltage at the first resistance circuit in response to applying a first current to the first resistance circuit, measuring a second voltage at the second resistance in response to applying a second current to the second resistance circuit, comparing the first and second voltages to determine a difference value, and determining that a current leak exists in the resistance temperature detector circuit when the difference value is not within a first range.
Abstract:
A liquid heater such as a direct electrical resistance liquid heater having multiple flow channels (48, 52) is provided with a temperature-sensing element in the form of a wire (76) extending across numerous channels, preferably all of the channels, near the downstream ends of the channels. The resistance of the wire represents the average temperature of the liquid passing through all of the channels, and hence the temperature of the mixed liquid exiting from the heater. A bubble suppressing structure (54) is provided in the vicinity of the wire.
Abstract:
Widerstandstemperatursensor (10) mit einem ersten Temperatursensorelement (6) und einem zweiten Temperatursensorelement (7), welches erste Temperatursensorelement (6) aus einer ersten Messstrecke besteht und welches zweite Temperatursensorelement (7) aus einer zweiten Messstrecke besteht, wobei die erste und die zweite Messstrecke auf einem Substrat (1) verlaufen, wobei das Substrat (1) eine anisotrope thermische Ausdehnung mit wenigstens zwei sich voneinander unterscheidenden Ausdehnungsrichtungen (a, c) aufweist, und wobei sich eine Projektion der ersten Messstrecke auf die Ausdehnungsrichtungen (a) von einer Projektion der zweiten Messstrecke auf die Ausdehnungsrichtungen (c) unterscheidet.
Abstract:
A fluid level detection system (10; 110; 210; 310; 410) includes a fluid reservoir (15; 15A, 15B, 15C; 15D; 15E, 15F, 15G, 15H; 115) defining a cavity (60; 160) for holding fluid therein. A fluid level sensor (12; 12A, 12B, 12C; 12D, 12E, 12F; 12G, 12H, 12I, 12J; 112) is mounted to the fluid reservoir. The solenoid body (20; 120) defines a first opening (62; 162) establishing fluid communication between an armature chamber (42; 142) and the cavity defined by the reservoir. Travel time of an armature (44; 144) within the armature chamber is thereby affected by fluid level in the reservoir. A controller (16; 16A; 16B; 116; 416) is operatively connected to the sensor and is operable to receive a sensor signal (17; 17A, 17B, 17C; 17D, 17E, 17F; 17G, 17H, 17I, 17J) indicative of travel time from the sensor and formulate a control signal (21; 21 A; 21B; 421) corresponding thereto. A power source (38; 38A; 38B; 138; 438) is operatively connected to the controller for energizing the coil and the controller. In some embodiments, multiple fluid containing components (15A, 15B, 15C; 15E, 15F, 15G, 15H) are connected with one or more controllers (16A; 416; 423). An engine (15E), a transmission (15F), and rear axle differentials (15G, 15H) on a vehicle may be equipped with sensors (12G, 12H, 12I, 12J) to provide fluid level, temperature and viscosity information.
Abstract:
A system for measuring temperature includes a thermowell, a primary temperature sensor, a reference sensor, and a transmitter. The thermowell has a measurement instrument connection and a side port. The primary temperature sensor extends into the thermowell through the measurement instrument connection, and the reference sensor extends into the thermowell through the side port. The transmitter is connected to each of the primary temperature sensor and the reference sensor. The transmitter has circuitry for measuring temperature based upon signals received from the primary temperature sensor and for concurrently calibrating based upon signals received from the reference sensor.