Rockwell Automation Allien-Bradley E3 Manual Del Usuario página 145

Figura 8.3 Ejemplo de programa de lógica de escalera
Rung 0: The 1747-SDN scanner module will map output data from its scanner output table (M0) and discrete outputs to each node
only when it is in the "run mode". This is accomplished by setting bit 0 of the 1747-SDN's command word (word 0).
Rung 1: If bit B3:0.0 is momentarily set, latch the bit in the output table that controls the E3's output relay.
i.e. Start the motor.
B3:0
0
Rung 2: If bit B3:0.1 is momentarily cleared, unlatch the bit in the output table that controls the E3's output relay.
i.e. Stop the motor.
B3:0
1
Rung 3: If a fault in the E3 is detected, send an explicit message to get the actual fault code.
Initiate
E3 Trip bit
Explicit Message
I:1 B3:0
4
16
1747-SDN
Rung 4: When the explicit message response has arrived, read the fault code.
I:1
15
1747-SDN
Rung 5: Provide an external method to reset faults..
B3:0
5
Ejemplo de aplicación de controlador lógico con mensajes explícitos
Scanner RUN Bit
O:1
( )
0
1747-SDN
E3 Output relay bit
O:1
(L)
16
1747-SDN
E3 Output relay bit
O:1
(U)
16
1747-SDN
COP
Copy File
Source #N10:0
Dest #M0:1.224
Length 32
Initiate
Explicit Message
B3:0
(U)
4
COP
Copy File
Source #M1:1.224
Dest #N9:0
Length 32
I:1
(U)
15
1747-SDN
E3 Fault Reset bit
O:1
( )
18
1747-SDN
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