The main difference from most other computing devices is that PLCs are intended-for and therefore tolerant-of more severe conditions (such as dust, moisture, heat, cold), while offering extensive input/output (I/O) to connect the PLC to sensors and actuators. PLC input can include simple digital elements such as limit switches, analog variables from process sensors (such as temperature and pressure), and more complex data such as that from positioning or machine vision systems. PLC output can include elements such as indicator lamps, sirens, electric motors, pneumatic or hydraulic cylinders, magnetic relays, solenoids, or analog outputs. The input/output arrangements may be built into a simple PLC, or the PLC may have external I/O modules attached to a computer network that plugs into the PLC

ASME Provide :

• Process automation systems and related hardware software and services.
• PLC business, as well as related hardware, software, services, I/O and bundled HMI
• Process safety systems
• SCADA systems for oil and gas, water and wastewater, and power distribution
• Process field instrumentation, such as temperature and pressure transmitters, fl owmeters, level transmitters and associated switches.
• Control valves, actuators and positioners
• Condition-monitoring equipment and systems
• Material-handling systems
• Other control hardware components, such as third-party
• Analytical equipment, including process electrochemical, all types of infrared technology
• PLC business, as well as related hardware, software, services,