| 摘要 |
PURPOSE:To cause a data collector unit to monitor correctly the trouble occurrence detection and the trouble recovery of a terminal controller and turn off a disconnection contact after reporting the transfer of the control to the terminal controller at a trouble recovery time. CONSTITUTION:Data collector unit 4 monitors polling signals, which terminal controller TC1 generates, by receiving part 9A of line adapter 5A, and discriminates the trouble of TC1 when the coming of polling signals is not detected over one second, and turns off disconnection contact 7. Unit 4 generates substitutive polling signals from transmission part 8B of adapter 5B in stead of TC1, and receives and stores data from each data entry unit 3-1 or 3-m through receiving part 9B of 5B. When TC1 starts to generate periodically polling signals again, unit 4 discriminates that the trouble is restored and transfers the control to TC1 and turns on contact 7. |
