摘要:
An automatic temperature compensation method that automatically adjusts trip point thresholds of a motor circuit protector in response to changes in temperature. The relationship between two curves is exploited to match temperature sensor readings from a temperature sensor circuit with burden resistor percentage values derived from a burden resistor circuit. A temperature inflection point is determined from the intersection of (1) the temperature sensor curve plotting the voltage output of the temperature sensor versus temperature and (2) the burden resistance curve plotting burden resistance versus temperature. A temperature value along the temperature sensor curve is transformed into the corresponding burden resistance on the burden resistance curve. The burden resistance is expressed as a percentage variance from a burden resistance at an ambient temperature. An adjusted trip point threshold is calculated from the computed burden resistor percentage, and the adjusted trip point threshold is stored in a memory.
摘要:
A bimetallic strip for a circuit breaker includes a substantially rectangular frame with two long sides, two short sides, a top side, and a bottom side. The long sides are slightly bent upwards. The first short side is securely mounted on the first terminal of the circuit breaker and has a length smaller than that of the second short side. A first saddle-like slot is defined at the first short side. A movable node mounted at the second short side and the bottom side. By means of changing the depth of the saddle-like slot, it is very easy for a manufacturer to make the metallic strips with various specifications of current ratings.
摘要:
A switch is described, having a housing 12 which receives a temperature-dependent switching mechanism 11 and which has a first housing part 15 on whose inner base 25 a first electrode 24 connected to a first external terminal 23 is arranged, as well as a second housing part 14, closing off the first housing part 15, that comprises a second electrode 20 connected to a second external terminal 22. The switching mechanism 11 creates, as a function of its temperature, an electrically conducting connection between the first and the second electrode 24, 20. A series resistor 34 is arranged in the housing 12, geometrically and electrically between the switching mechanism 11 and one of the two electrodes 20, 24.
摘要:
A resettable, current-responsive, circuit interrupter device has two wide but thin terminals embedded up to a substantial part of their thickness in a side wall of an insulating housing so that sides of the embedded terminal portions are exposed from the housing material along the side wall inside the housing. Terminal ends extend from the bottom of the housing to be connected in a circuit and extend through the top of the housing to be accessible for test purposes. An electrical contact is mounted on the exposed side surface of one embedded terminal portion and a thermostatic strip element is secured to the exposed side surface of the other embedded terminal portion to extend closely along the one housing side to normally engage the contact in a very compact, closed circuit position of the device. A lid overlies the thermostatic strip element. The thermostatic strip element has a selected resistivity and the wide terminals have substantial current capacity so the thermostatic strip self-heats to a selected temperature to open the circuit in response to occurrence of a precisely predetermined overload current condition in the device circuit at any ambient temperature likely to be encountered in an automotive environment.
摘要:
A light responsive control and overload protection circuit for low voltage illumination systems includes means responsive to ambient light for providing an enabling output. Control means respond to the enabling output for switching heating current on when enabled. Heat-producing means is provided. The heating current passes through the heat-producing means whenever the control means is enabled. Heat-responsive circuit breaker means are in circuit between a low voltage power source and the load. The heat-producing means is thermally coupled to the heat-responsive circuit breaker means to transfer heat thereto and effect and maintain an opening thereof whenever sufficient ambient light is present. Heat-responsive means respond to heat from the heat-producing means to prevent the overheating thereof during overloads and load circuit short circuiting.
摘要:
A method of assembling a temperature responsive resistance member within a pair of separable housings. This method includes the steps of: mounting the temperature responsive resistance member in both supporting engagement and electrical contacting engagement between a pair of electrical terminals; and joining the separable housings against displacement so that the temperature responsive resistance member in both the supporting engagement and the electrical contacting engagement with the terminals is disposed within the housings in predetermined spaced relation therewith with portions of the terminals extending exteriorly of the housings.