The current loop uses DC power because the magnitude of the current represents the signal level that is being transmitted. If AC power was instead used in the loop, the magnitude of current would be continuously changing, making it difficult to discern the signal level being transmitted.In this session we are gonna discuss about Difference between …
Difference between 2 wire & 4 wire transmitter current loops Read More »
How a current loop works A typical 4-20 mA current loop circuit is composed of four individual elements: a sensor / transducer; a voltage to current converter (commonly referred to as a transmitter and / or signal conditioner); a loop power supply; and a receiver / monitor. In loop-fed applications, the four elements are connected …
What is Stroke Checking of Control Valves? All control valves need to be stroked after some time in service. This is due to the fact that the valve is a mechanical mechanism that has physical components. These components must constantly be in excellent functioning condition in order to prevent the valve from failing. Stroking the …
Introduction Another type of instrument commonly seen in measurement and control systems is the process switch. The purpose of a switch is to turn on and off with varying process conditions. Usually, switches are used to activate alarms to alert human operators to take special action. In other situations, switches are directly used as control devices. …
Calibration principle: Calibration Setup Safety Link: Basic Safety and General Consideration While Executing Calibration Process in process industries Method of calibration Range selection: Zero calibration: Span Calibration: Calibration verification: Expected current (mA) = ((Actual liquid level / Full scale level) * 16) + 4 EC = {(AL/FL) X16} +4 EC = Expected current signal in …
Calibration of capacitance type level transmitter Read More »
What is an ELCB? Earth Leakage Circuit Breakers are safety devices that provide additional protection against earth leakage. ELCB is employed in places where the earth impedance is high. The primary objective of these devices is to reduce the risk of shock in the event of a current flow to the earth. When energy “leaking” …
What is a Differential Pressure Transmitter? The Differential pressure transmitter is commonly used in industries as pressure measuring instrument. It is a device that measures two opposing pressures in a pipe or a vessel. This equipment will sense the difference in pressure between two ports and produce an output signal with reference to a calibrated pressure range. In the Differential pressure transmitter, as …
HOW TO CALIBRATE DIFFERENTIAL PRESSURE TRANSMITTER? Read More »
What is calibration? In measurement technology calibration is the process of checking the instrument with a standard instrument to improve the measuring functions. The accuracy of standard device taken for calibration should be 10 times the accuracy of measuring device. What is control valve? Control valve is used to monitor the flow of fluid by …
What is Transmitter? Transmitters are instruments used to generate and send electromagnetic waves which includes message or signal. A transmitter produces radio waves with the help of Antenna. Transmitter itself combines a sensor and the sensor measures the process variable and generates proportional signal. What is the working principle of Transmitter? The working principle of …
What are the differences between transducer and transmitter? Read More »
Zero suppression & Zero elevation are values that correspond to the 4-20mA transmitter range for level measurement using Differential pressure transmitter (DPT). In signal conditioners, in particular, zero suppression and zero altitudes relate to a reduction (deletion) or angle (altitude) of the nominal “zero” yield so that it is not at zero volts (or milliamps). …
