Abstract: A drawout unit that disconnects both polarities of DC current from a DC source, when all poles are used for one of the polarities leaving no pole available to disconnect the other polarity. The drawout unit includes a disconnect device having a four-pole switch, and all four poles are series-connected to the positive (ungrounded) polarity. A separate drawout module with its own housing is connected to the negative (grounded) polarity, and together, the disconnect device and the drawout module are positioned in a cradle with a racking mechanism for racking both the device and the module in and out of the cradle simultaneously, thereby obtaining total isolation of both polarities. In this configuration, the installer has the option to ground the negative polarity, while leaving the positive polarity ungrounded. The drawout module has a through bar conductor that passes the negative polarity of the DC current through the drawout unit.

Abstract: A drawout unit that disconnects both polarities of DC current from a DC source, when all poles are used for one of the polarities leaving no pole available to disconnect the other polarity. The drawout unit includes a disconnect device having a four-pole switch, and all four poles are series-connected to the positive (ungrounded) polarity. A separate drawout module with its own housing is connected to the negative (grounded) polarity, and together, the disconnect device and the drawout module are positioned in a cradle with a racking mechanism for racking both the device and the module in and out of the cradle simultaneously, thereby obtaining total isolation of both polarities. In this configuration, the installer has the option to ground the negative polarity, while leaving the positive polarity ungrounded. The drawout module has a through bar conductor that passes the negative polarity of the DC current through the drawout unit.

Abstract: An improved filter assembly for a circuit breaker includes a generally rectilinear filter housing having at least two filter mounting zones for receiving at least two filter assemblies, so as to define, in the aggregate, a filter assembly, and at least two filter assemblies configured for interfitting with the filter mounting zones of the filter housing, each filter assembly comprising a generally rectilinear filter body having a given peripheral configuration and a filter gasket configured for interfitting about a periphery of the filter body for sealingly engaging the filter body relative to the filter housing in response to forces encountered by the filter assembly both upon assembly and in operation. The filter assembly may further have a small hole diffuser having a peripheral configuration similar to the peripheral configuration of the filter bodies, in the aggregate, when assembled with the filter housing and configured for interfitting within the filter housing.

Abstract: A blade assembly for use in a circuit breaker, the blade assembly comprising a plurality of blades, including one or more pairs of adjacent side-by-side blades having coplanar contact surfaces and coplanar bearing surfaces, at least one set of blade springs, each having one end in operative contact with the bearing surface of each of a pair of adjacent side-by-side blades, the at least one set of blade springs comprising at least one compression spring.

Abstract: An improved filter assembly for a circuit breaker includes a generally rectilinear filter housing having at least two filter mounting zones for receiving at least two filter assemblies, so as to define, in the aggregate, a filter assembly, and at least two filter assemblies configured for interfitting with the filter mounting zones of the filter housing, each filter assembly comprising a generally rectilinear filter body having a given peripheral configuration and a filter gasket configured for interfitting about a periphery of the filter body for sealingly engaging the filter body relative to the filter housing in response to forces encountered by the filter assembly both upon assembly and in operation.

Abstract: A blade assembly for use in a circuit breaker, the blade assembly comprising a plurality of blades, including one or more pairs of adjacent side-by-side blades having coplanar contact surfaces and coplanar bearing surfaces, at least one set of blade springs, each having one end in operative contact with the bearing surface of each of a pair of adjacent side-by-side blades, the at least one set of blade springs comprising at least one compression spring.

Abstract: An industrial-rated molded case circuit breaker employs a pair of movable contact arms to interrupt circuit current through each phase of a multi-phase electrical power distribution circuit. A contact arm guide outboard the movable contact upon overcurrent conditions. A pair of protrusions formed on the abutting surfaces of the contact arms prevents the arms from distortion under the electrodynamic attraction generated during intense overcurrent conditions. A flexible arc gas exhaust-seal is arranged between the movable contacts and the line strap connectors to seal the circuit breaker enclosure while controllably exhausting the arc gases that occur upon such intense overcurrent conditions.

Abstract: A circuit breaker having a contact assembly with a double pivot arrangement. The moving arcing and main contacts provide a smooth surface for meeting the lower arcing contact and the lower main contacts, each mounted on a separate semi-stationary lower blade. The lower arcing contact is positioned higher than the lower main contact, making the arcing contact the last to separate from the moving contact. An arc horn is mounted adjacent the moving contacts to provide a path for movement of the arc from the upper contact into the arc stack assembly. The arc horn has three fingers, each of which passes through the cutaway portion of each arc plate of the arc stack assembly upon the contacts separating.

Abstract: A mechanical time delay mechanism is shown which provides a predetermined time delay between the movement of the moving contact blade on a circuit breaker and the activation of a switch. The control circuit design of the circuit breaker provides for tripping at one level when the breaker is in the closed position and at a second lower fault level when the circuit breaker is closing and for a predetermined number of cycles thereafter. The subject time delay mechanism activates a switch to change the tripping level from the second level to the first level at the appropriate time. The mechanism includes a pivot link assembly connected directly to the moving contact arm, a ratchet assembly, and a pivot link connecting the two. The pivot link assembly includes a set of springs to delay the movement of the link with respect to the movement of the pivot link in response to an opposing pull on the link.

Abstract: A low resistance electrical connector adapted to allow for various types of misalignment between conductors including a furcated terminal block which carries a plurality of adjustable wafers that include a bevelled forward surface. Each wafer includes a recessed top and bottom channel as well as opposite lateral channels. Helical contact members are positioned in grooves provided in the top and bottom channels to provide electrical connection between the wafer and the terminal. Similar contact members are carried in the lateral channels of each wafer for engagement with a female connector.