Patent ID: 9748024
Date: 2017-08-29
CPC Classifications: B23K,H01B,H01H,H02B

Claim:
1. A passive arc control system for a motor control center, comprising: an arc attenuating box surrounding an individual, vertical bus bar phase at a point of electrical connection between a circuit interrupting device and the vertical bus bar, sides of the arc attenuating box separating and sequestering one vertical bus bar phase from an adjacent vertical bus bar phase, the arc attenuating box being configured to provide a physical barrier to arc flash energy and gases intruding into an adjacent arc attenuating box surrounding an adjacent bus bar, the arc attenuating box being open at its top and bottom to form a chimney along the vertical bus bar to provide directed venting of arc flash energy and gases out of the motor control center; and a shutter assembly including an insulator cap on a free end of the vertical bus bar and an independently moveable, box-shaped shutter composed of an insulator material, which slides horizontally within the arc attenuating box, the box-shaped shutter being configured to slide along the vertical bus bar away from the insulator cap, in response to a force applied by a leading edge of a connector assembly for the circuit interrupting device, when the device is being connected to the vertical bus bar, the main body of the box-shaped shutter having an opening through which the vertical bus bar passes when the device is connected to the vertical bus bar, the box-shaped shutter being open top to bottom, with the opening aligned with the top to bottom opening in the arc attenuating box, in both the connected and disconnected positions of the device, as part of the chimney formed along the vertical bus bar.