Introduction Time delay devices are used for delaying the start-up, shutdown, recycling, or continuation of processing operations until the desirable requirements have been satisfied or the required conditions have been obtained.In this session we are gonna discuss about the different types of time delay relays Dashpot or Pneumatic In a “dashpot” type delay, the armature of …
Introduction The time delay relays are special purpose relays or logic components that have some characteristics of both relays and Timers Timing is one of the variables of any process, and often needs to be monitored or controlled. Some operatives the steps in a process may need to match or may need to be separated …
Description The dead weight tester apparatus consists of a chamber that is filled with oil-free impurities and a piston-cylinder combination is installed on top of the chamber as shown in the diagram. The upper part of the piston is connected to a platform for loading weights. A piston with handle has been provided to vary …
Introduction The energy distribution systems used in large commercial and industrial applications can be complex. Power can be distributed through switchgear, electrical panels, transformers and boards. Energy distributed through a commercial or industrial application is used for a variety of applications such as heating, cooling, lighting and motor-driven machinery. Unlike other types of power distribution …
Valve guiding is necessary for proper alignment with the seat ring and efficient control of the process fluid. The common method used are listed below: Cage guiding: The cage allows positive alignment and control of the plug. The outside diameter of the valve plug is close to the inside wall surface of the cylindrical cage …
Introduction One of the most common electric motors used in most applications is known as an induction motor. This motor is also called an asynchronous motor because it operates at a speed less than its synchronous speed. Here we have to define what is synchronous speed. Synchronous speed is the speed of rotation of the …
INTRODUCTION The purpose of an alarm system (annunciator) is to bring attention to an abnormal or unsafe operating condition in the plant. Traditional annunciators used discrete alarm modules for this purpose. These dedicated hardware units are diminished in numbers but they are used in installations where simplicity is desired or where separation from the basic …
Pressure relief valves: Pressure relief valves are safety valves that are designed to prevent internal pressure from rising above a predetermined maximum pressure in a pressure vessel exposed to abnormal or emergency conditions. Spring Loaded Design: The valve consists of an inlet valve or …
Definition of Transformer A transformer is a static machine used for transforming power from one circuit to another without changing frequency. This is a very basic definition of Power Transformer. Since there is no rotating or moving part so transformer is a static device. Transformer operates on ac supply. Transformer works on the principle of mutual induction. History …
Introduction Microprocessor relays provide many functions that were not available in electromechanical or solid-state designs. Relay logic is very important to understand the microprocessor-based relay. The relay can be ON or OFF, that is, it has two stable states. Fig: Microprocessor based overcurrent relay Similarly, the output of a logic function is activated, that …
