摘要:
A circuit breaker having a shunting contact structure with low watts loss and high withstand level. The circuit breaker of the present invention comprises an upper contact arm having a first contact disposed thereon and a lower contact arm having second and third contacts thereon with the second contact mating with the first contact. A shunt terminal is provided between the upper contact arm and the lower contact arm. The shunt terminal includes a fourth contact which mates with the third contact on the lower contact arm. The circuit breaker of the current invention has a closed, open and current limiting position. When the circuit breaker is conducting nominal rated current, the first, second, third and fourth contacts remain closed. When the circuit breaker is under fault conditions which are circuit current conditions above the withstand level, the circuit breaker switches to a current limiting mode. In this mode, the upper contact arm and the lower contact arm move simultaneously in an upward and downward manner respectively, thereby opening the third and fourth contacts resulting in a blow open loop that opens the first and second contacts and protect a load coupled to the device from overcurrent conditions.
摘要:
A method and apparatus generates an enhanced trip time curve capable of capturing both the non-sinusoidal energy and series effects. Relevant data including time, current, and energy is plotted on a three-dimensional set of axes. The resultant three-dimensional representation is useful for representing trip times for a protection device accounting for energy effects, and for determining selectivity in a multi-tier electrical distribution system.
摘要:
An integrated protection unit is a circuit interrupter which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. One such accessory used with the integrated protection unit is a bell alarm for indicating the status of the circuit interrupter contacts.
摘要:
A compact molded case circuit breaker with increased ampere rating employs a latch assembly for maintaining the circuit breaker operating mechanism in a closed condition against a pair of powerful operating springs. To increase the mechanical advantage required to move the operating handle against the springs, a retractable handle extender is attached to the handle. For higher-rated circuit applications, a lug cover extension is added to the line end of the breaker to assist in extinguishing the intense arc that occurs during circuit interruption and to protect the line lugs from inter-phasal circuit faults. A visual access slot is arranged next to the circuit breaker handle to ascertain and verify the condition of the circuit breaker contacts.
摘要:
A compact molded case circuit breaker with increased ampere rating employs a latch assembly for maintaining the circuit breaker operating mechanism in a closed condition against a pair of powerful operating springs. To increase the mechanical advantage required to move the operating handle against the springs, a retractable handle extender is attached to the handle. For higher-rated circuit applications, a lug cover extension is added to the line end of the breaker to assist in extinguishing the intense arc that occurs during circuit interruption and to protect the line lugs from inter-phasal circuit faults. A visual access slot is arranged next to the circuit breaker handle to ascertain and verify the condition of the circuit breaker contacts.
摘要:
A method and apparatus generates an enhanced trip time curve capable of capturing both the non-sinusoidal energy and series effects. Relevant data including time, current, and energy is plotted on a three-dimensional set of axes. The resultant three-dimensional representation is useful for representing trip times for a protection device accounting for energy effects, and for determining selectivity in a multi-tier electrical distribution system.
摘要:
A molded case circuit breaker base is configured to receive pole modules that include the circuit breaker components for mutipole operation. The base is configured to receive the bottom edges of the module enclosures in press-fit relation. A complementary molded case circuit breaker cover attaches to the top of the modules to complete the multipole circuit breaker enclosure.
摘要:
An electric circuit breaker enclosure includes a pultruded glass-filled plastic inset for added strength to the line and load terminal straps. The line and load terminal straps are fastened to the inset on the side and receive the corresponding line and load terminal cables on an opposite side thereof. The inset allows connection within a high-rated electrical power distribution circuit without damage to the circuit breaker case upon short circuit interruption.
摘要:
Since industrial-rated circuit breakers are often located remote from the associated protected electrical equipment it is often times necessary to monitor the operation of such electrical equipment by observing the condition of the circuit breaker contacts to ensure that such equipment remains operational. When a plurality of such circuit breakers are mounted within a common enclosure, an auxiliary device within each of the circuit breakers readily provides visual indication of the ON-OFF condition of the circuit breaker contacts. With such auxiliary devices, an actuator-reset lever is used to interface between the circuit breaker operating mechanism, the circuit breaker trip mechanism and the auxiliary device to activate the auxiliary device when the circuit breaker contacts are open and closed and to reset the trip mechanism when the circuit breaker contacts are opened.
摘要:
A compact molded case circuit breaker with increased ampere rating employs a latch assembly for maintaining the circuit breaker operating mechanism in a closed condition against a pair of powerful operating springs. To increase the mechanical advantage required to move the operating handle against the springs, a retractable handle extender is attached to the handle. For higher-rated circuit applications, a lug cover extension is added to the line end of the breaker to assist in extinguishing the intense arc that occurs during circuit interruption and to protect the line lugs from inter-phasal circuit faults. A visual access slot is arranged next to the circuit breaker handle to ascertain and verify the condition of the circuit breaker contacts. The line and load terminal straps are slotted to receive protrusions on the bottom of the line and load terminal lugs and provide anti-turn facility to the line and load terminal lugs under short circuit overcurrent conditions.