| 摘要 |
PROBLEM TO BE SOLVED: To maintain the uniform power feed speed of a hot-line insertion/ removal device regardless of the insertion speed of a circuit package(PKG). SOLUTION: When PKG is inserted, the long terminal 12 comes in contact with the power terminal -48V and the power feed moderately starts according to the time constant formed by the resistance for the soft start 14 and the internal capacity. Next, the short terminal 13 comes into contact. However, when the insertion speed of PKG is fast and PKG is inserted faster than the setting time of the timer circuit 17, the power feed is not performed because the switch 16 is off, and the voltage variance and rush current are not generated. If the switch 16 is on by the timer circuit 17 after passing the setting time, the power feed starts at the short terminal 13 side and then the voltage variance and rush current is not generated because the voltage reaches to -48V. The timer circuit starts to count when it is detected that the voltage generated from the resistance 14 for the soft start in PKG exceeds the threshold level. |
