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(1) control requirements
Motors M1, M2, M3 three drive belt conveyor.Press the start button SB1, start the order of M1, M2, M3, the interval of 3s.Press the stop button SB2, the order of the parking for M3, M2, M1, the interval of time is 3s. Three motors M1, M2, M3 respectively through the contactor KM1, KM2, KM3 connected three-phase AC power supply, with PLC control of the coil of the contactor.
(1) control requirements
Motors M1, M2, M3 three drive belt conveyor.Press the start button SB1, start the order of M1, M2, M3, the interval of 3s.Press the stop button SB2, the order of the parking for M3, M2, M1, the interval of time is 3s. Three motors M1, M2, M3 respectively through the contactor KM1, KM2, KM3 connected three-phase AC power supply, with PLC control of the coil of the contactor.
(2)Address allocation table for programming elements
|
Programming element
|
I/O terminals
(program address)
|
Circuit devices
(PT timer value)
|
function
|
|
input relay
|
I0.0
|
SB1
|
start button
|
|
I0.1
|
SB2
|
Stop button
|
|
|
output relay
|
Q0.0
|
KM1
|
M1 Contactor
|
|
Q0.1
|
KM2
|
M2 Contactor
|
|
|
Q0.2
|
KM3
|
M3 Contactor
|
|
|
Timer(100ms)
|
T37
|
50
|
Start first period of time
|
|
T38
|
50
|
Start second period of time
|
|
|
T39
|
30
|
Parking first period of time
|
|
|
T40
|
30
|
Parking second period of time
|
|
|
Auxiliary relay
|
M0.0
|
–
|
Parking holding first
period of time
|
|
M0.1
|
–
|
Parking holding second period
|
(3)Ladder Diagram
 |
| PLC ladder programming |
PLC ONE 