Omron SYSMAC CX-Programmer 8.1, Руководство по эксплуатации

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SFC Programming Example Section 1-4
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1-4 SFC Programming Example
The section provides a simple example of an SFC program, and describes the
procedures for program development using CX-Programmer.
1-4-1 Simple Example of an SFC Program
SFC will be used to program a ticketing system for an unattended paid parking lot.
Study the action flow scenario and clarify the steps and transition conditions.
Check for external devices, also, and define the variables.
Vehicle Sensor
Gate Close Limit Sensor
Ticket Dispenser
Ticket Sensor
Gate Open Limit Sensor
Action Flow Scenario for an Unattended Paid Parking Lot
A scenario is created by breaking down the action flow, as well as the statuses of the
external device.
1 Waiting for an incoming car. -> Step 1: Initial step
2 When a car enters, the vehicle sensor is turned ON, and the active status is
transferred to the next step.
-> Transition condition: Trans1/Vehicle sensor ON (carln)
3 When the vehicle sensor is turned ON, the ticket dispenser is turned ON, and a
ticket is issued.
-> Step 2: TicketOut
-> AQ: N (Normal)
-> Action: Active ticket dispenser
4 When the ticket dispenser issues a ticket, the ticket sensor is turned OFF.
5 When the driver takes the ticket, the ticket sensor is turned OFF, and the active
status is transferred to the next step. At this point, the ticket dispenser is also
turned OFF.
-> Transition condition: Trans2/Ticket sensor ON (ticket)
6 When the driver takes the ticket, normal rotation of the gate motor is turned ON,
and the gate begins to open.
-> Step 3: OpenGate
-> AQ: N (Normal)
-> Action: Active normal rotation of gate motor
7 When the gate is fully opened, the gate open limit sensor is turned ON, and the
active status is transferred to the next step.
At this point, the normal rotation of the gate motor is turned OFF.