What is a Thermopile ?
A thermopile is an electronic device that converts thermal energy into electrical energy. It is composed of several thermocouples connected usually in series or, less commonly, in parallel. Thermocouples operate…
What to Choose RTD or Thermocouple ?
Thermocouples (TCs) and resistance temperature detectors (RTDs) are the most widely used temperature sensors in automation and process control. They are found embedded in motors, valves, turbines, bearings, and a…
How a 4 Wire RTD Works ?
4 Wire RTD Principle The most accurate lead wire configuration is the “true” 4-wire configuration. In a true 4- wire configuration, the resistance of the lead wires does not contribute…
What is PID Controller Bumpless Transfer ?
Bumpless Transfer Bumpless transfer is either a manual or automatic transfer procedure used when switching a PID controller from auto to manual or vice versa. Its aim is to keep…
Feedforward Vs Feedback Control
Feedback control Feedback control is an important technique that is widely used in the process industries. Its main advantages are as follows. Corrective action occurs as soon as the controlled…
PID Controllers with Output High Select Logic
The below figure 1 shows a typical control scheme with two controllers driving the same control valve via high select logic. The controller PIC-1 is the main pressure controller and…
Overview of Split Range Control
A very common control scheme is split range control in which the output of a controller is split to two or more control valves. Split Range Control For example: Controller…
Self Actuated Pressure Control Valve Principle
Self actuated pressure control valve do not depend on any external signal for pressure control. As the name suggests, pressure in the process line itself is used as an actuating signal…
Zero Speed Switch Working Principle
Monitoring Speed is essential in any automation process. Speed of any equipment driven by an electric motor can very due to variety of reasons e.g. overload, underload, breakage of transmission…
Overview of Proximity Switches
A proximity Switch is a sensor able to detect the presence of nearby objects without any physical contact. Application:- Proximity switches provide better alternative to the conventional electro-mechanical limit switches for…
