need help with rotary potentionmeter

[zefiris2K5]

can somebody tell me how to use this rotary potentiometer?

i've done a little research and this what i get. (result)

and also a few pict about it.

 

[Roff]

Does it have a part number printed on it?

 

[Russlk]

Your research was not very useful. It looks like a dual pot. What do you want to do with it?

 

[zefiris2K5]

part number...... not really sure....:?
it have.....

s/n no : 2/00/77
type : D7359/4
unnamed field: B65/64/56/SS

it is another type of potentiometer. the resistance of the potentiometer increase with the rotation of the potentiometer. i want to measure angle swivel with this thing and it's compulsory.

 

[Roff]

part number...... not really sure....:?
it have.....

s/n no : 2/00/77
type : D7359/4
unnamed field: B65/64/56/SS

it is another type of potentiometer. the resistance of the potentiometer increase with the rotation of the potentiometer. i want to measure angle swivel with this thing and it's compulsory.

I couldn't find anything on those numbers. What do you need help with?

 

[zefiris2K5]

i want to know on how to use it. maybe a method to fix the reading as i state earlier that the reading varies from time to time ?.

 

[Russlk]

To calibrate, measure the resistance change over 180 degrees. Then, when it is turned an unknown amount, you can calculate the degrees from the resistance change. The pot is no doubt linear, or it is useless. I don't understand why you could not figure that out?

 

[zefiris2K5]

what i mean is the resistance of the pot increase as the rotation speed increase. there are no limitation of degree. the problem i face here is the reading is unstable at constant rotation speed.

 

[akg]

what i mean is the resistance of the pot increase as the rotation speed increase. there are no limitation of degree. the problem i face here is the reading is unstable at constant rotation speed.

'..is the resistance of the pot increase as the rotation speed increase.." what type of pot is that ?

 

[Nigel Goodwin]

It sounds more like a rotary encoder than a pot?.

 

[Russlk]

That is the problem with digital meters, the response time is so slow it is not evident that the resistance is bouncing between zero and open!

 

[philba]

maybe I'm missing something but this seems like much ado about (almost) nothing. If it really is a pot, it's probably either linear or audio taper. easy enough to find out with a couple of readings (don't turn it while taking a reading). If its an encoder, that should become apparent, too.

"readings vary from time to time" confuses me. does that mean that you can set the pot to a specific angle and then take two readings and get different results? I'd get another pot if that's the case. If turn it causes fluctuations in the resistance measurement, it may be a DMM sample problem or wiper noise.

"there are no limitation of degre" does that mean you can turn the pot more than 360 degrees? if so it is either a) broken, b) an encoder or c) a motor.

It's not clear what you want to do with this "pot". Maybe if you told us about the application we could help you.

 

[Roff]

maybe I'm missing something but this seems like much ado about (almost) nothing. If it really is a pot, it's probably either linear or audio taper. easy enough to find out with a couple of readings (don't turn it while taking a reading). If its an encoder, that should become apparent, too.

"readings vary from time to time" confuses me. does that mean that you can set the pot to a specific angle and then take two readings and get different results? I'd get another pot if that's the case. If turn it causes fluctuations in the resistance measurement, it may be a DMM sample problem or wiper noise.

"there are no limitation of degre" does that mean you can turn the pot more than 360 degrees? if so it is either a) broken, b) an encoder or c) a motor.

It's not clear what you want to do with this "pot". Maybe if you told us about the application we could help you.

There are pots that will rotate continuously through 360 deg. Their electrical angle is usually not more than 340 deg.

 

[philba]

dang, you are, of course, right. servos often have them. and there are lots of multiturn pots, though more common in trimmers.

 

[zefiris2K5]

That is the problem with digital meters, the response time is so slow it is not evident that the resistance is bouncing between zero and open!

Maybe you right.

and from the manufacturer site...

Operating Life - Greater than 50 million rotations

that's right...rotation...not turn....

i bet you guys never seen this type of potentiometer.

 

[Nigel Goodwin]

i bet you guys never seen this type of potentiometer.

Are you sure that's what you've got?, the numbers you quoted don't bear any relation to the link you posted, and the picture is useless.

If it is a pot?, then it's very simple to prove it with a multimeter.

As has been asked previously more than once, what are you trying to do with it?, and for that matter why?.