What is a non contact digital tachometer?

Question

what's the use and what it controls?
the componets/parts that can be found inside the device.
how it used/control.
the range of detecting (sensor).
how is built and some relevant websites?
***please make my day.
thanx

Answer 1

A digital tachometer generally uses a laser light to detect rotations and calculates the rpm. it uses the principle of reflection of light from a surface. the rotating shaft / teeth has got markings on surface. the device detects the interval between reoccurance of same mark/blank space and calculates the rpm.

Answer 2

Hi Lloyd I have used this equipment in the water treatment industry. Basically it is a hand held stroboscope with a calibrated dial which can be locked. I used it to check the speed of pumps and blowers prior to overhaul to see if the maximum speed was below manufactures specification. The drive coupling would be cleaned and a magnetic piece of self adhesive tape put on the coupling. Every-time the strobe hit the tape it would register 1rpm. when the machinery had reached maximum speed the needle was locked for taking a reading. I used to hire the equipment from a specialist instrument company. Maybe if you do a search for instrument hire you may get some more technical information. Hope this helps

Answer 3

Not a full answer, but this likely uses a magnetized portion of a shaft to sweep a magnetic field past a very close, but not touching, sensor. The sensor could be anything from a coil that has some voltage induced by the passing field to a spin valve type sensor like in older disk drive heads.

Answer 4

http://www.omega.com/ppt/pptsc.asp?ref=HHT10&Nav=h01

http://www.geneq.com/catalog/en/poktach.htm

http://www.burntec.com/tektools/Pdf2/461501.pdf#search='What%20is%20a%20non%20contact%20digital%20tachometer'