| 摘要 |
PURPOSE:To perform the detection of the loop reverse from a following position compatibly with the transmission of a special signal from a preceding position, by connecting a battery for the special signal to or grounding a loop reverse signal circuit where a bridge circuit and secondary winding relay are connected for the detection of a following-position answer. CONSTITUTION:When contact b<0> of OGT10 operates, a current flows from the battery of ICT20 and relay A of ICT20 operates. At this time, relay P of OGT10 never operates because currents flowing through winding (1-2) and winding (3-4) cancel mutually. Similarly, relay H of ICT20 is not in operation. On the other hand, as special-signal sending contact r<0> of OGT10 operates, OGT10 is held at the same potential with ICT20 by the battery and currents flow through neither relay H (3-4) nor relay A (3-4) of ICT20. Therefore, only relay H of ICT20 operates through the operation of contact r<0> of OGT10. |
