Control System Components syllabus

Switches: Principle, symbolic representation, working, application of Toggle switch, Slide switch, DIP switch, Rotary switch, Thumbwheel switch, Selector switch, Push button, Drum switch, Limit switch, Temperature switch, Pressure switch, Level switch, Flow switch. Relays: Working, specifications/selection criteria and applications of electromechanical relay, Solid state relays. Contactors: Working, specifications and applications of contactors. Comparison between relay & contactor.

Standard symbols used in motor control wiring diagrams. Sequencing and Interlocking Concepts: Applications in motor control: Start and stop operations, Emergency shutdown procedures and Direct-On-Line (DOL) and Star-Delta starting methods. Motor Protection Techniques: Short circuit protection, Overload protection, Low/under-voltage protection, Phase reversal protection and Over-temperature protection. Advanced Motor Control Operations: Reversing the direction of motor rotation, Braking methods, Variable speed starting and Jogging and inching controls. Motor Control Canters (MCCs): Concept and wiring diagrams of MCCs for industrial applications.

Comparison in between Pneumatic, hydraulic & electrical systems. Pneumatic & Hydraulic components: Pneumatic & Hydraulic Power Supply and its components, Cylinders: Single acting & Double acting cylinder, Cushion, Double rod, Tandem, Multiple position, Rotary. Pneumatic & Hydraulic motors. Direction controlled valves and flow control, Special types of valves like relief valve, pressure reducing, Time delay valve, Pneumatic relay (Bleed & Non bleed, Reverse & direct). Pneumatic & Hydraulic Circuits: Standard Symbols used for developing pneumatic & hydraulic circuits, Sequence diagram (step-displacement), Direction control, Speed control, Reciprocating, Sequencing, and Meter in, Meter out for hydraulic circuits.

Principle, characteristics, specifications and applications of SCR, UJT, TRIAC, DIAC, MOSFET, IGBT, Triggering and Commutation of SCR. Circuit Breaker and Fuses. Actuators: Advantages, disadvantages and applications of spring and diaphragm, piston cylinder actuators and smart actuators. Design of a spring and diaphragm actuators.

Control valve terminology: Rangeability, turndown, viscosity index, valve capacity, distortion coefficient, AO, AC, fail-safe actions, cavitation, flashing and noise, their effects and remedies. Control valve characteristics: Inherent and installed. Control valve classification: advantages, disadvantages and applications of globe- Single seated, double seated, 3-way, diaphragm, rotary, angle, Gate, Needle, ball and butterfly valve. Designing control valve for gas, vapor and liquid services: valve sizing by ANSI/ISA 75.01 std., high temperature-pressure service valves. Positioners: Need, applications, types, effect on performance of control valve. Definition of Cavitation and Flashing.