industrial instrumentation basics

Pressure is one of the four process variables — alongside temperature, flow, and level — that shows up in nearly every industrial process. Understanding how it's measured, what instrument to pick for a given job, and how to calibrate that instrument correctly is core knowledge for any instrumentation technician. This article walks through the fundamentals: what pressure actually is, the scales used to express it, the sensing technologies behind pressure gauges and transmitters, and a practical calibration procedure you can use in the field. What Is Pressure? Pressure is force applied per unit area. In a process plant, pressure shows up almost everywhere — fluid flowing through a pipe, gas in a vessel, differential pressure across an orifice plate used for flow measurement, and so on. Pressure readings are affected by more than just the process itself. Altitude, weather, and atmospheric conditions all influence a pressure measurement, which is why pressure is expressed using a...

  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 meas...

Solenoid valve A solenoid valve or SOV is an electro mechanically 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 valv...

What Flow Measurement Is Actually Doing Flow measurement means tracking how much material — liquid, gas, or solid — passes a point per unit of time. It's measured two fundamental ways: on a volumetric basis (volume per time) or a mass basis (weight per time). Gases are almost always measured volumetrically, since compressing or heating them changes their volume dramatically. Liquids can go either way depending on the application. Solids are typically measured by weight, since volume is a poor indicator for bulk materials of inconsistent density. One distinction worth keeping straight: liquids are essentially incompressible — the same mass occupies roughly the same volume regardless of pressure. Gases are compressible — the same mass can occupy very different volumes depending on pressure and temperature. This is why gas flow measurements are typically corrected back to standard conditions (0°C, 760 mmHg, or your plant's defined reference) before they're usable for mass b...