Let’s assume that the escalator does not move until someone approaches it.
When someone approaches the escalator and turns on pass detection switch: 0, the illumination lamp lights and the escalator starts to move. (Escalator movement is up only).
The person is carried up by the escalator, and when that person moves off the escalator, pass detection switch: 1 turns ON, and the illumination lamp and escalator return to a non-operating state.
In this PLC ladder program example, consider both pass detection switches: 0 and 1 as non-hold type switches.
Another assumption in this PLC Ladder Program example is that people do not continue to get on this escalator.
PLC Input and Output assignment:
PLC Input
Pass detection switch: 0
X000
PLC Input
Pass detection switch: 1
X003
PLC Output
Illumination lamp
Y000
PLC Output
Escalator drive output
Y003
PLC ladder Program for Control of Escalators
PLC Ladder Program for Control of Escalators 1
Ladder Program for Control of Escalators 2
PLC program Explanation for Control of Escalators:
When input X001 is turned ON, outputs Y000 and Y003 operate. Next, when input X003 is turned ON, outputs Y000 and Y003 become non-operational.
