Search results
Results from the WOW.Com Content Network
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity that requires high reliability, ease of programming, and process fault diagnosis.
Standard IEC 61131 is divided into several parts: [3]. Part 1: General information. It is the introductory chapter; it contains definitions of terms that are used in the subsequent parts of the standard and outlines the main functional properties and characteristics of PLCs.
Part 3 of IEC 61131 deals with basic software architecture and programming languages of the control program within PLC. It defines three graphical and two textual programming language standards: Ladder diagram (LD), graphical; Function block diagram (FBD), graphical; Structured text (ST), textual
A feedback control loop is directly controlled by the RTU or PLC, but the SCADA software monitors the overall performance of the loop. For example, a PLC may control the flow of cooling water through part of an industrial process to a set point level, but the SCADA system software will allow operators to change the set points for the flow.
Siemens SIMATIC S7-300 PLC CPU with three I/O modules attached. As with other programmable logic controllers, SIMATIC devices are intended to separate the control of a machine from the machine's direct operation, in a more lightweight and versatile manner than controls hard-wired for a specific machine. Early SIMATIC devices were transistor ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
PLC technicians also find employment in the industrial engineering field where they are actively involved in the design and implementation of PLC control systems. Career opportunities for PLC Technicians include a wide range of manufacturing and service industries such as automotive, pharmaceutical, power distribution , food processing , mining ...
A simplified PAL device. The programmable elements (shown as a fuse) connect both the true and complemented inputs to the AND gates. These AND gates, also known as product terms, are ORed together to form a sum-of-products logic array.