Programmable Logic Controller (PLC)

Categories:
Stand Alone Controllers

Description

A Programmable Logic Controller (PLC) is a rugged digital computer used to control machines, processes, and automation systems in industrial environments. PLCs are designed to withstand harsh conditions such as dust, moisture, temperature extremes, and electrical noise.

Unlike traditional computers, PLCs are optimized for real-time control and reliability. They operate by continuously monitoring input devices (such as sensors and switches), executing logic-based programs, and controlling output devices (such as motors, lights, or actuators).

PLCs are widely used in manufacturing, packaging, conveyor systems, energy management, water treatment, building automation, and other sectors requiring precise and reliable control.

Request Quote

Specifications

  • CPU (Central Processing Unit):

    • Executes control logic

    • Memory: typically supports 2k to 64k logic steps (expandable in advanced models)

  • Power Supply:

    • Common voltage levels: 24V DC, 120V AC, 230V AC

    • With internal or external battery backup for data retention

  • Inputs/Outputs (I/O):

    • Digital Inputs: Receives ON/OFF signals from switches, sensors, etc.

    • Digital Outputs: Sends ON/OFF signals to relays, lights, solenoids, etc.

    • Analog Inputs/Outputs: Used for variable signals like temperature, pressure, or level

    • Expandable via I/O modules

  • Communication Ports:

    • Serial: RS232, RS485

    • Ethernet: Modbus TCP, Profinet, Ethernet/IP

    • Wireless or cloud communication available in advanced models

  • Programming Languages (IEC 61131-3 standard):

    • Ladder Logic (LD)

    • Function Block Diagram (FBD)

    • Structured Text (ST)

    • Instruction List (IL)

    • Sequential Function Chart (SFC)

  • Programming Interface:

    • PC-based software (e.g., Siemens TIA Portal, Allen-Bradley RSLogix, Omron CX-Programmer)

    • USB, Ethernet, or proprietary programming cable

  • Mounting:

    • DIN rail or panel-mounted

    • Modular or compact design depending on brand

  • Operating Environment:

    • Temperature: Typically -10°C to +60°C

    • Humidity: 5% to 95% non-condensing

    • Vibration and shock-resistant housing

  • Cycle Time:

    • Fast scan time, typically from 1 ms to 10 ms per logic cycle (application-dependent)

  • Brands and Models:

    • Siemens (S7-1200, S7-1500)

    • Allen-Bradley (MicroLogix, CompactLogix)

    • Mitsubishi (FX Series)

    • Omron (CP1E, CJ2)

    • Schneider (Modicon M221/M340)

  • Typical Applications:

    • Conveyor belt and motor control

    • Packaging and bottling systems

    • Automated lighting and HVAC control

    • Water pump and level systems

    • Industrial robotics and sensors

Back to Products