Advantages of PLCs over Conventional Relay-Based Control Systems

PLCs provide significant advantages over conventional relay-based control systems

Improved Reliability

Once written and tested, a program can be simply transferred to different PLCs. The PLC’s memory stores all logic, eliminating the possibility of wiring errors.The application replaces much of the external wire that is ordinarily necessary to control an operation. Hardwiring is still required to connect field devices, although it is less intensive. PLCs also provide the reliability that comes with solid-state components.

More Flexibility

Creating and changing programs with a PLC is easier than wiring and rewiring circuits. With a PLC, the user program determines the relationships between inputs and outputs rather than how they are interconnected. Original equipment.

Manufacturers can give system updates by simply releasing a new program. End users can change the application in the field, and if necessary, security can be provided via hardware features such as key locks and software passwords.

Lower Cost

PLCs were originally developed to replace relay control logic, & the cost savings have been significant enough that relay control is becoming obsolete, except in power applications.

In general, if an application requires more than a half-dozen control relays, installing a PLC will likely be less expensive.

Communicate Capability

A PLC can interface with other controllers (or) computer equipment to conduct operations such as supervisory control, data collection, device and process parameter monitoring, and software download and upload.

All logic is stored in the PLC memory. The user program determines the input-output relationships. Contactor Light Solenoid Outputs Inputs Pushbutton Limit switch Sensor

Faster Response Time

PLCs are intended for high-speed, real-time applications. The programmable controller functions in real time, which implies that an occurrence in the field triggers the execution of an operation or output.

The PLC’s quick-response capacity is essential for machines that process thousands of items per second and objects that interact with sensors in fractions of a second.

Easy to Troubleshoot

PLCs include built-in diagnostics and override functions that allow users to readily identify and solve software and hardware issues.

To detect and solve problems, users can display the control program on a monitor & watch it run in real time.