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Speed of rotating machine measured by
Clip on meter
Phase sequence indicator
Techo-meter
Thermometer
Techo-meter
A tachometer (often misspelled as techo-meter) is a measuring instrument used to measure the rotation speed of a shaft or disk in a motor or other machine. It displays the revolutions per minute (RPM) on a calibrated analog or digital dial.
A tachometer (often misspelled as techo-meter) is a measuring instrument used to measure the rotation speed of a shaft or disk in a motor or other machine. It displays the revolutions per minute (RPM) on a calibrated analog or digital dial.
N=T60тАЛ тАФ where N is speed in RPM and T is the period of one revolution in seconds.
N=P60├ЧfpulseтАЛтАЛ тАФ where fpulseтАЛ is frequency in Hz and P is the number of pulses per revolution.
Tachometers function based on various physical principles including electromagnetic induction, optical reflection, or mechanical centrifuges. For instance, an optical tachometer detects reflected light pulses from a reflective marker on the rotating shaft, calculating speed as N=t60тАЛ, where t is the time interval between pulses in seconds.
Tachometers can be contact type (mechanical) or non-contact type (optical/laser).
Essential for monitoring induction motors, alternators, and industrial conveyors.
The term 'Tachometer' is derived from the Greek word 'tachos' meaning speed.
Precise measurement of real-time rotational speed
Non-contact variants ensure no mechanical loading on the motor shaft
Mechanical contact types are subject to wear and friction
Optical types require reflective markers to be cleaned regularly
Industrial motor speed control monitoring
Automotive dashboard speedometers
Testing of rotating machinery in power plants
Clip-on meters are used for current measurement (ammeters).
Phase sequence indicators are used to determine the order of phases in 3-phase systems.
Thermometers are used for temperature measurement, not motion.
C is correct тАФ A tachometer is the standard instrument used to measure the rotational speed of a machine shaft in RPM.
Always verify if the question asks for electrical parameters (like current/voltage) vs mechanical parameters (like speed), as clip-on meters are strictly for current, while tachometers are for motion.