Features of the Extech 461920 Tachometer Mini Laser Tachometer Counter
- Make non-contact RPM measurements of rotating objects
- Use reflective tape on object to be measured and point the integral laser
- Large 5 digit LCD display with backlighting
- Memory button for Last/MAX/MIN readings
- Counter function counts up to 99,999 revolutions
- Rugged, double molded housing
Extech 461920 Tachometer Applications:
Motor speed, moving fans, pumps, and gears, propeller devices, and many other general maintenance, production, and automotive uses.
What is a Tachometer? A tachometer is a device that measures the angular speed of a rotating shaft in terms of revolutions per minute (RPM). Also, a tachometer can measure linear speed in terms of feet per minute (feet/minute) or meters per minute.
How do Contact Tachometers Operate? The sensor tip is placed in direct contact with the rotating object. After 2 seconds an accurate reading is displayed. Linear surface speed can also be measured by placing the edge of the wheel on the moving object.
How do Photo (Non-contact) Tachometers Operate? First, a small piece of reflective tape (approximately 1/4-inch) is mounted on the object to be measured. Second, the light beam or laser is pointed at the revolving tape. The reflection from the tape provides a reading to be displayed and updated once per second. For the most accurate measurements, the distance between the tachometer and the reflective tape should be within 6 inches for a light beam and up to 6.5 feet for a laser. Fluorescent or bright ambient lights may interfere with the measurement.
Which Extech Tachometer Model Is the One for You? A non-contact (photo) tachometer was designed for applications where it is not feasible to have the tachometer come in contact with the rotating device. This is the case in high-speed applications and/or where the object to be measured is not easily reached. A contact tachometer is also available for applications where direct contact of the tachometer with the object is preferred. You can also select a combination (contact/non-contact) tachometer for the maximum in flexibility.
Accessory: Reflective Tape for Photo Tachometers For use with any brand Photo Tachometer. Place a piece of reflective tape on the object to be measured and point the tachometer’s integral light beam at it. Ten reflective tape strips. Each strip measures 585 x 6 mm.