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Triplett Full Product Catalog: Volume 1 Now Available



Triplett provides non-contact and contact tachometers that assure fast and accurate RPM measurements of rotating objects and count (REV) measurements and linear speed measurements. Our contact and non-contact laser photo tachometers come with a certificate of traceability to NIST standards. Many mechanical equipment and devices like engines, pulleys and shafts used across industries have rotating or spinning parts. The rotations per minute (RPM) is a measure of rotation of these parts in a minute and it implies their working efficiency. This RPM is measured using tachometers, which may be contact and non-contact types.


Know More About Triplett Tachometers

What is a photo tachometer?

Photo tachometers are portable, handheld devices, which use non-contact method of RPM measurement. These devices ensure the conversion of RPM into electrical pulses, which can be easily measured. We provide photo tachometers designed to assure fast and accurate non-contact rotational speed (RPM) and total revolutions (REV) measurements. Laser RPM tachometers are a type of photo tachometer.

Photo tachometers are commonly used to measure the rotational speed of motors, engines, fans, conveyors, and other rotating machinery. By accurately measuring RPM, they help in ensuring proper equipment operation, identifying abnormalities, and maintaining optimal performance.

What are laser tachometers?

Laser tachometers, also known as laser photo tachometers or laser digital tachometers features a laser on the end of the device, which is usually focused on the rotating object to measure its RPM. Laser tachometers are non-contact type tachometers, usually preferred in hard-to-access areas such as confined spaces, engines of industrial machinery, and so on. Laser tachometers can be used for various distances, depending on your model. The Triplett TA200 tachometer and TA150 Tachometer are both laser RPM tachometers, which assure accurate long distance measurements. The Triplett Model TA150 Tachometer can be used to measure RPM for a 1.6 ft (500mm) maximum target distance. However, the Triplett TA200 tachometer is designed for laser-guided non-contact measurement with 8.2ft (2500mm) maximum target distance.

What are the types of digital tachometers?

Digital tachometers are distinguished into two types – contact and non-contact types.

  • Non-contact Tachometer: The non-contact types feature a light source, which produces a focused beam and bounces off reflective surfaces. Whenever a component or part rotates, the light from the reflector hits the sensor located in the tachometer. The tachometer counts each time the light hits the sensor in a given timeframe. This result is then expressed in revolutions per minute.
  • Contact Tachometers: These tachometers feature a free spinning wheel that comes in contact with the rotating surface. The wheel is propelled by the surface, and this produces pulses. These pulses are interpreted by the tachometer as RPM. Many contact tachometers are also used to measure linear speed and distance. The Triplett TA200 Tachometer is a type of contact tachometer used for a wide range of linear surface speed measurements such as meters per minute, feet per minute, inches per minute, and yards per minute. They can also be used to measure the length of products such as sheets and wires in meters, feet, inches, and yard.

What are the applications of laser photo contact tachometers?

Laser photo contact tachometers can be used in various applications across industries. The following are a few common uses:

  • Vehicles and automotive
  • Boats and marine vehicles
  • Maintenance and routine industrial operations
  • Machinery and mechanical systems
  • Research and development
  • Laboratories, test and measurement

How to prepare a digital tachometer for measurements?

Follow the below-given steps to prepare contact and non-contact tachometers for measurements.

Non-contact (Photo) Tachometers

  1. Apply a small piece of tape to the surface of the rotating object under test.
  2. Ensure to fix the tape closer to the outer edge of the object subjected to the test.
  3. If your device has a meter collar, then ensure to remove it.
  4. Start taking the measurements by pointing the tachometer onto the surface.

Contact Tachometers

  1. Avoid step 3 if you are taking contact measurements.
  2. Attach the meter collar if not already done.
  3. Slide the adapter of the contact device onto the shaft of the tachometer.
  4. Ensure to align the adaptor and the alignment pin on the contact adaptor.
  5. Next, attach the contact measurement accessory such as a wheel, cone, and concave accessory onto the contact adaptor.
  6. Use the contact meter to measure the surface length and surface speed.

Are there any considerations to make when taking non-contact (photo tachometer) measurements?

Yes, there are certain considerations to make while taking measurements using non-contact tachometers.

  • The bright ambient light produced by the tachometer may interfere with a light beam that reflects from the operational surface. In this scenario, you must shade the target area. The non-reflective area must be kept larger than the reflective area.
  • Most surfaces are reflective. You can cover it with paint or black tape before applying the reflective tape. If you are taking low RPM measurements, ensure to use additional squares of reflective tape. You can calculate the RPM by dividing the reading on the digital display by the squares of reflective tapes.
  • Keep the tachometer closer to the rotating surface to derive accurate readings. Ensure to keep the tachometer at least 15cm from the surface.
  • Avoid taking measurements with dim laser light. A bright laser helps in accurate speed measurement.

How to choose the right tachometer for your industrial applications?

There are certain things to keep in mind when choosing industrial tachometers for your applications. Our experts will help you with the right selection, however, the following pointers will be helpful in this context.  

  • Can you access the equipment under consideration?
  • Is it safe to go near the equipment to make a direct contact?
  • Do you want to measure other factors like RPM, linear distance, and surface speed using your tachometer?

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