Mechanical vibration switches

A much simpler alternative to continuous vibration sensors (displacement or acceleration) and monitoring equipment suitable for less critical applications is a simple mechanical switch actuated by a machine’s vibration. These switches cannot, of course, quantitatively analyze machine vibrations, but they do serve as qualitative indicators of gross vibration....
Continue reading »

What is Weighfeeders ?

A special type flowmeter suited for powdered or granular solids is the weighfeeder. One of the most common weighfeeder designs consists of a conveyor belt with a section supported by rollers coupled to one or more load cells, such that a fixed length of the belt is...
Continue reading »

How to calibrate an RTD ?

Introduction:-There are two types of calibrations applicable to PRTs—characterization and tolerance testing. The type of calibration to perform is determined by the way in which the UUT is to be used and the accuracy required by the user. Characterization is the type of calibration in which the unit...
Continue reading »

Feedforward control

  Feedback control works on the principle of information from the outlet of a process being “fed back” to the input of that process for corrective action. A block diagram of feedback control looks like a loop: The reason any control system is necessary at all to...
Continue reading »

Supervisory control

In a manually-controlled process, a human operator directly actuates some form of final control element (usually a valve) to influence a process variable. Simple automatic (“regulatory”) control relieves human operators of the need to continually adjust final control elements by hand, replacing this task with the occasional adjustment...
Continue reading »

How to Ultrasonic flowmeters work ?

Ultrasonic flowmeters measure fluid velocity by passing high-frequency sound waves along the fluid flow path. Fluid motion influences the propagation of these sound waves, which may then be measured to infer fluid velocity. Two major sub-types of ultrasonic flowmeters exist: Doppler and transit-time. Both types of ultrasonic flowmeter...
Continue reading »

Ziegler-Nichols Tuning method

Ziegler-Nichols open-loop tuning procedure :- The first process tuned in simulation was a “generic” process, unspecific in its nature or application. Performing an open-loop test (two 10% output step-changes made in manual mode, both increasing) on this process resulted in the following behavior: From the trend, we...
Continue reading »

Working principle of Magnetic flowmeter

When an electrical conductor moves perpendicular to a magnetic field, a voltage is induced in that conductor perpendicular to both the magnetic flux lines and the direction of motion. This phenomenon is known as electromagnetic induction, and it is the basic principle upon which all electro-mechanical generators operate....
Continue reading »