3
\$\begingroup\$

After a slight purchasing mishap, I am to end up with an encoder whose max RPM is too low for the application for which it is to be used. To achieve roughly the same purpose (that is, sensing of an angle) with a lower budget, we are now looking to use a potentiometer. Just to make sure that we don't make the same mistake again, is there a maximum speed which potentiometers can generally be turned? Say, something faster than the 60 RPM max we found out about on the purchased parts? I've looked through the data sheets for a couple different potentiometers, but I can't seem to find anything (though I suppose that makes sense since these potentiometers are fixed rotation).

Any advice is appreciated.

\$\endgroup\$
5
  • \$\begingroup\$ Well to get a potentiometer that can turn all the way around for continuous rotation use it is for sure a specialty part and not your normal garden variety pot that supports a 270 degree turn. I would venture to suggest that very few pots are going to be rated for operation in continuous operational mode. The wipers will soon wear a track in the resistive element. These things are generally designed for the usage as humans turning up and down the volume on a radio!! So if you have a specialty part you really should carry on a conversation with the manufacturer. \$\endgroup\$
    – Michael Karas
    Commented Dec 31, 2014 at 7:59
  • \$\begingroup\$ Have you considered using a hall sensor instead? \$\endgroup\$
    – Ignacio Vazquez-Abrams
    Commented Dec 31, 2014 at 8:00
  • \$\begingroup\$ Perhaps i should clarify. In this case, we are thinking of using a fixed rotation potentiometer, which will only allow an angle measurement of a bit over 180 degrees. The decision was made due to very low available budget; we weren't able to find anything that serves the same purpose (various encoders, hall sensors, etc) that meets the same budget restrictions (read: couple dollars each max) \$\endgroup\$
    – Vasu
    Commented Dec 31, 2014 at 8:30
  • \$\begingroup\$ You could perhaps use gearing to reduce the rpm seen by the encoders. \$\endgroup\$
    – markt
    Commented Dec 31, 2014 at 9:11
  • \$\begingroup\$ Unfortunately, there isn't a good combination of gearing given the max speed and encoder steps. \$\endgroup\$
    – Vasu
    Commented Dec 31, 2014 at 9:14

1 Answer 1

Reset to default
4
\$\begingroup\$

What you need is typically called a "servo mount" potentiometer, that is - designed to be mounted to and turned by a motor (as part of a servo loop) rather than by a human (e.g. the typical bushing mount). Sometimes they are found under slightly different terms as well, Vishay refers to them as "Precision Rotative Transducers" in this datasheet. The maximum rotation speed is specified as 600 RPM on the "ES" model (ball bearing, servo mount). Specified life is 30 million cycles.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.