- 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.