PLC I/O
PLC input / output
A controller interface point connecting field signals to an identified module channel.
Schematic
Symbols · DI
PLC digital input
A PLC digital input reads a documented discrete electrical state from field wiring.
Schematic · DI
What it represents
A PLC digital input reads a documented discrete electrical state from field wiring. The schematic identifies input channel, signal common and field supply as required by the chosen module.
How to read it
- Check whether the input expects sourcing or sinking field wiring.
- The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation.
Information to show or reference
- Identify channel address
- Show input common/supply
- Reference field signal polarity
A distinction that matters
A digital input reads a state; it does not provide the power output used to drive an actuator.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Modicon TM3 digital I/O hardware guide
Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. DXF uses unscaled drawing units; a GA envelope supplies no product dimensions, clearances or fabrication information. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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