| 摘要 |
<p>In high-voltage switchgear, apparatus for preventing two switches from being closed at the same time to prevent their being electrically paralleled relative to a common bus. The position of each switch is mimicked by a rotatable cam having a notch. When either switch closes while the other switch is fully open, its cam moves a member into the path of the notch in the other cam which is blocked from rotating, preventing the other switch from closing. If both switches attempt to close simultaneously, the member either blocks both cams or blocks one while permitting the other to rotate. If one switch attempts to close while the other switch opens, its cam continues to be blocked until the one switch is returned to full open.</p> |
