| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the extraction of a box to be unit-tested in a state, where the front door of the box is closed by commonly using one box to be unit-tested by attaching four circuits come into contact with the turning on/off test switches when the box is inserted, and a unit testing device which is only non-conducted, when the box is inserted to the frame surface on the front side of a board. SOLUTION: When a built-in circuit breaker 12 is at its operating position, the turning-on/off operation of a CS 6 is performed, after it has been confirmed that the condition of an interlock 9 is met, and no electrical accident happens from a closed relay 11a. When the circuit breaker 12 is pulled out to a testing position, a position detecting limit switch 2 tilts to 2b side, and full sequence tests including the condition of the interlock 9 and the confirmation of an electrical accident 11 are performed by means of the CS 6. When a single switch box 4 is inserted, the B1 and B2 of a normally-closed hub jack 3 are non- conducted and, successively, closed circuit terminals A1 and A2 and opened circuit terminals C2 and C2 are connected. When the built-in test PPs 7 and 8 of the switch box are pressed, the circuit breaker 12 is closed and unit tests can be conducted.</p> |
