| 摘要 |
<p>A direct current electrical switching apparatus (2) includes a first contact (12) in electrical communication with first and third arc runners (4,8), a second contact (14) in electrical communication with second (26) and fourth arc runners (6,10), a movable contact (16), a first arc chamber (22) including first arc plates (30) having a first width (31), a second arc chamber (32) including second arc plates (40) having a greater second width (41), an operating mechanism (42), and a magnet assembly (44) cooperating with the arc chambers to establish generally oppositely directed magnetic fields (46). The magnetic fields cause one of a first arc (48) and a second arc (50) to enter one of the arc chambers depending upon a direction of current flow between the contacts. The electrical switching apparatus is rated for a first magnitude of current flowing from the first contact to the second contact and for a greater second magnitude of opposite second current flowing from the second contact to the first contact.</p> |
