Partial ladder diagram of system control

For ladder diagram design, the relationships between AND, OR and NOT
are easy to implement. The delay link can complete its function by using the timer of PL.C. A more
complicated point is the reset latching between XV-101, PV-102, and XV-102.
Figure 26-10 shows the ladder diagram to implement this latching relationship.
    The figure has the following definition: MO. 6: Total fault point; io.2: PV-102 reset signal
; IO.0 : XV-101 reset signal; QO,Ot PV-102; 00.1: XV-102;
00.2: xv-lol.
    Various alarm indications, including indicator lights, bells or other sound alarm systems , are
directly driven through the output contacts of the PLC (relay type).
    (4) Conclusion Production processes such as nitric acid production are very harmful due to accidents
. By controlling the interlocking alarm system with Lih PLC , the reliability and safety of the system are improved, and the amount of maintenance is small. In
the case where there is a computer monitoring system, information can also be transmitted to the host computer through the PLC communication cable to realize the supervision of the distributed control system,
so that the control system can adapt to the control requirements of complex industrial production processes.