Mitsubishi Electric FX2N Beginners Manual page 59

An Introduction to Programming
Assignment of the input and output signals
The task description clearly defines the number of inputs and outputs needed. The gate drive
motor is controlled with two outputs. The signals required are assigned to the PLC inputs and
outputs as follows:
Function
Inputs
Outputs
Timer
The program components
b Operation of the rolling shutter gate with the pushbuttons
The program must convert the input signals for the operation of the gate into two commands for
the drive motor: "Open Gate" and "Close Gate". Since these are signals from pushbuttons that
are only available briefly at the inputs they need to be stored. To do this we use two relays to
represent the inputs in the program and set and reset them as required:
– M1: open gate
– M2: close gate
Ladder Diagram
X001
0
X002
M100
4
X004
7
X005
M200
11
The signals for opening the gate are processed first: When key-operated switch S1 or button
S2 are operated a signal is generated and M001 is set to a signal state of "1" for just one pro-
FX Beginners Manual
STOP button
OPEN key-operated switch
(outside)
OPEN button (inside)
Upper limit switch (gate open)
CLOSE button (inside)
CLOSE button (outside)
Lower limit switch (gate closed)
Photoelectric barrier
Warning lamp
Motor contactor (motor reverse)
Motor contactor (motor forward)
Delay for automatic close
M2
M1
Programming PLC Applications
Name Adress Remarks
Break contact (when the switch is opera-
S0 X0
ted X0 = "0" and the gate stops)
S1 X1
Make contacts
S2 X2
Break contact (X2 ="0" when the gate is
S3 X3
up and S3 is activated)
S4 X4
Make contacts
S5 X5
Break contact (X6 = "0" when the gate is
S6 X6
down and S6 is activated)
X7 is set to "1" when an obstacle is
S7 X7
registered
H1 Y0 —
K1 Y1 Reverse = OPEN gate
K2 Y2 Forward = CLOSE gate
— T0 Time: 20 seconds
PLS M100
SET M1
PLS M200
SET M2
Instruction List
0 LD X001
1 OR X002
2 PLS M100
4 LD M100
5 ANI M2
6 SET M1
7 LD X004
8 OR X005
9 PLS M200
11 LD M200
12 ANI M1
13 SET M2
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