Unlimited Potentiometer

[Atomic_Sheep]

Hi Guys,

Just wondering what an unlimited potentiometer is called i.e. a potentiometer that doesn't have a max and a min level i.e. one that you can rotate freely for as long as you want in any direction.

[GoingForGold]

Maybe you mean unlimited rotory encoders?

[gfesim]

If you are really looking for a potentiometer (and not an encoder), then look for "endless potentiometer" like this one here:

http://www.piher.net/sensors/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=41&category_id=2&option=com_virtuemart&Itemid=31#

In most cases these are standard pots with just the stop removed. With some types of pots you can remove the stops yourself.

What would you try to achieve with that ?

And then there are multi-rotation pots, with ten or more turns. But they eventualy have a stop.

Gerald

[xplanematt]

Do note that even most of the fancy-schmancy potentiometers have an ELECTRICAL limit (that one says 340*, for instance), even though it may be capable of infinite turns. This means you can't reliably track the pot position through a complete turn.

It's possible to construct a "combo" pot with onboard electronics that figures up shaft position from multiple carbon tracks, but I recommend a Hall encoder:

http://www.madscientisthut.com/Shopping/agora.cgi?cart_id=9525106.11869&product=CNC%20/%20Robotic%20Sensors&user4=Rotary%20Encoder&xm=on

I've used the AS5040 for an altimeter project, I attached it and a magnet to the back of a synchro. It worked FLAWLESSLY and is very precise.

Matt