摘要 |
A circuit for protecting the power contacts (18, 20) of automatic bus transfer equipment, including high speed solid state switches (30, 32) connected across the respective contacts. A timing and steering circuit (36) is responsive to the electrical energization of a solenoid (22) for firing the solid state switch (32) connected across the closed contact (18). A timer (48) is responsive to the opening of the contacts (18). At the elapse of a time period, the firing circuit (34) is caused to operate the solid state switch (30) before the closing of the contacts (20). The solid state switch (30) is maintained operated for a predetermined period of time by a timer (90).
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