PLC Is Programmable Control System Which Reduced Complex Hardwired Relay Logic. Programmable Logic Controller (PLC) Store Instructions To Control Industrial Machines, Systems And Processes. Controlling Process Is Depends On Inputs, Outputs Condition Of System.

For Reading These Analog Signals In PLC Required Special Type Of Hardware Which Is Known As Analog Module. Analog Input Module Are Basically Use Analog-To-Digital Converter (ADC) For Converting Analog Signal Into The Digital Signal. Analog Output Module Use Digital-To-Analog Converter (DAC) For Converting Digital Signal Into Analog Signal. These Module Perform Amplification, Filtering, Signal Conditioning So We Receive A Proper And Exact Value.

Variables Are The Name Of Occupied Memory Area That Used For Write Or Store Value, Variables Are Declared With A Specific Data Type, Which Determines The Type Of Data That Can Be Stored In The Variable.

Data Types Represent Values Such As Numbers, Real Numbers, Strings, And Boolean Values, Each Data Type Has A Specific Range Of Values And Operations That Can Be Performed On It. All Data Type Have Some Reserved Memory For Storing Value In That Memory.

An Array Is A Data Structure That Can Store Multiple Values Of The Same Data Type Under A Single Variable Or Single Tag. Array Are Useful For Large Amounts Of Data Complex Sets Of Data.

It reduced human error and provides continues result of process or system. plc save fuel, cost, processing material, labor and increased production. below are some common question for plc asked in interview.

Learn about different PLC communication types, protocols like Modbus, Profibus, Ethernet/IP, and how PLCs exchange data in industrial automation systems.

Learn the basics of the Modbus protocol including its types (RTU, TCP), communication principles, and how it is used in industrial automation for PLC and SCADA systems.

Prepare for your PLC interview with this easy-to-understand guide covering the most common and important PLC questions and answers. Useful for both beginners and experienced professionals.

Learn the difference between Sink and Source in PLC input/output modules. Understand how sourcing and sinking works with examples, wiring, and voltage references.

Prepare for your next job with these top 50 instrumentation interview questions and answers for beginners and experienced professionals in process and automation industries.

Learn everything about SCADA (Supervisory Control and Data Acquisition) systems – including its definition, components, history, real-world industrial applications, and how it revolutionizes automation and monitoring in industries.

Learn what a Distributed Control System (DCS) is, its architecture, components, advantages, real-world applications, and key interview questions. Ideal for automation, instrumentation, and control engineers.

Get the most comprehensive list of DCS (Distributed Control System) interview questions and answers tailored for freshers and experienced professionals. Learn about DCS architecture, control loops, communication protocols, HMI, SCADA integration, real-world case studies, and troubleshooting tips. Perfect guide for job interviews in automation and process industries.