摘要:
A circuit breaker including a trip unit having an internal support and a friction adjustment control system for knob control is provided. The internal support includes a first opening to receive a first rotary knob having one or more first smooth rings and a second opening to receive a second rotary knob having one or more second smooth rings. The trip unit includes a first knob control of the first rotary knob. The first knob control includes a first structural support, a first housing and a first spring installed in the first housing against the first structural support. The trip unit further includes a second knob control of the second rotary knob. The second knob control includes a second structural support, a second housing and a second spring installed in the second housing against the second structural support.
摘要:
A trip unit in a miniature circuit breaker includes a magnetic yoke and a bimetal mounted on the outside of the yoke. The bimetal is welded at one end to a load terminal that leads to a terminal connector and at the other end to a pigtail. The pigtail, instead of the bimetal, passes through the yoke for connection to the blade of the circuit breaker. To induce a higher magnetic field for faster tripping, a second pigtail may be passed through the yoke in which one end of the second pigtail is connected to the load terminal near the terminal connector and the other end is connected to the bimetal near the load terminal connection point. The load terminal may include at least two parts, one part including the adjustment screw and the other part including the terminal screw. These parts may be separated by air or an insulator.
摘要:
This concerns a molded case circuit breaker having separable main contacts and an operating mechanism utilized to cause the separable main contacts to open and close. A trip unit is provided to actuate the operating mechanism in desirable circumstances. The trip unit is removable. In this case the trip unit is insertable into a trip unit region in the case of the circuit breaker from the top or end thereof. The trip unit is then joined to an internal electrical conductor by way of a bolt and an internally fixed nut. The bolt can be driven into the nut through the trip unit conductor and the internal conductor from a position external to the circuit breaker case. The trip unit can be inserted into the trip unit conductor from a point above the circuit breaker case or vise versa. The trip unit has a securement nut built into its case.
摘要:
A separable circuit breaker includes a separate trip apparatus portion, having a trip apparatus and a trip apparatus container, and a switching apparatus portion having a switching apparatus and a switching apparatus container. The switching apparatus and trip apparatus are connectable by connection terminals in a lower part of the respective containers. The trip apparatus portion also includes a trip apparatus cover connected to an upper portion of the trip portion container and an assistant cover rotatably connected to an upper portion of the trip apparatus cover. The assistant cover allows access to the trip apparatus. The trip appartus includes a bimetal element and an armature. The switching apparatus portion includes a crossbar and a handle. The crossbar is connected and engaged with the armature according to deformation of the bimetal element such that current flow through the circuit breaker can be opened by rotation of the crossbar when an overcurrent exists. The handle can close the circuit after it has been opened by the overcurrent condition.