industrial instrumentation basics

 Pressures Measurement in instrumentation In the following pages, we will discuss all the basics of pressure measurement, such as, What is pressure,  what is the definition of pressure,  units of pressure measurement, types of pressure sensors, working principle of different pressure primary elements, and applications of different sensors, pressure transmitter, and their calibration procedure.  What is Pressure? The force per unit area is called pressure. Three main methods are used to measure pressure, absolute pressure, gauge pressure, and differential pressure.  Pressure varies depending on the altitude of the site where we are measuring pressure.  Weather, pressure fronts, and other conditions also affect the measurement of pressure in a process. The measurement of pressure is relative to all these factors of weather and climate, and pressure measurements are carried out in two main scales  1. gauge pressure  2. absolute pressure. Gauge pressure Gauge pressure is the scale conside

  Vibration measurement Definition:  Vibration is defined as a periodic motion of the particles of an elastic body in alternatively opposite direction from the position of equilibrium. Acceleration, velocity, and displacement are the main parameters in vibration measurement. Unit of vibration   unit of vibration is mm/ sec. Types of vibration There are two main types of vibration measurement performed in the industry .   Axial Vibration This is a longitudinal vibration, it is measured in parallel to the shaft of a motor. This type of measurement is done to detect a shaft misalignment. Radial Vibration   This vibration occurs as a force applied outward from the shaft. Radial vibration would occur if there is a heavy spot in the motor as it rotates. If there is a deformed fan blade, as the fan spins, the deformed fan blade would pull outwardly on the shaft of the motor causing radial vibration. Types of vibration sensor Following are types of vibration measurement 1. Accelerometer  2.

Solenoid valve A solenoid valve or SOV is an electromechanically operated valve.  This is controlled by an electric current through a solenoid coil, a magnetic field is produced in the electrical coil which mechanically operates the plunger of the valve and hence changes the path of air or fluid from one direction to another direction. Types of solenoid valve: 2/2-way solenoid valve This type of valve has 2 ports and it acts in  2 positions.  It means the solenoid valve has two ports one is the inlet port and another port is the outlet port, material passing through the solenoid valve either pneumatic or fluid is applied to the inlet port and exhausted through the outlet port. Two-position of solenoid valve means that its piston or plunger has two-position, either valve is open or close. 3/2-way solenoid valve  This type of valve has 3 ports and 2 acting positions. 5/2 way solenoid valve  This type of valve has 5 ports and 2 positions. Types of a solenoid valve according to operation 

 Flow Measurement Definition: The amount of  material passing through a specific point in a specific time is  called the flow of that material Flowmeter What is a flow meter? Flowmeter is a device that is used to measures the rate of flow or total quantity of fluid moved in an open or closed conduit.  Units of flow  Cubic meter/sec Liter / sec Liter/minute Liter/ hour Barrel per sec Ton/hour Flow measurement methods Industrial flow measurements include measuring the flow rate of solids, liquids, and gases.  There are two basic methods used to measure flow in industrial instrumentation. 1. On a volumetric basis 2. On a weight basis.  As for as Gas flow is concerned it is usually measured on a volumetric base. Solid materials flow is measured either by weight per unit of time or mass per unit of time. Very rarely solid material flow quantity is measured in terms of volume.  On the other hand as for as Liquids are concerned the flow is measured either in volume rate or in weight rate. Cl