Encoder Basics
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Re: Encoder Basics
Question
Lead, Pitch, TPI all refer to different things but numerically are all equivalent?
*Note in below example TPI is actually 5.08 according to my arithmetic.
5mm Lead = 5mm Pitch = 5 TPI*
Is this correct?
Lead, Pitch, TPI all refer to different things but numerically are all equivalent?
*Note in below example TPI is actually 5.08 according to my arithmetic.
5mm Lead = 5mm Pitch = 5 TPI*
Is this correct?
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Re: Encoder Basics
The DMM servo encoder out will work with Acorn.
Clay
Clay
near Winston-Salem, NC
unofficial ACORN fb group https://www.facebook.com/groups/897054597120437/
near Winston-Salem, NC
unofficial ACORN fb group https://www.facebook.com/groups/897054597120437/
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Re: Encoder Basics
Thanks for the reply Clay
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Re: Encoder Basics
BigWillie, lead and pitch are the same. TPI is not - it is the inverse of the others. A 0.2" pitch is 1/0.2 = 5 TPI.BigWillieStyle wrote: ↑Fri Jan 05, 2018 1:03 am Question
Lead, Pitch, TPI all refer to different things but numerically are all equivalent?
*Note in below example TPI is actually 5.08 according to my arithmetic.
5mm Lead = 5mm Pitch = 5 TPI*
Is this correct?
Pitch is how far a screw advances in one turn. TPI is turns per inch. So if one turn moves 0.2 inches then 5 turns move one inch. Metric screws are normally specified based on pitches. Imperial screws are classified on turns per inch.
Your example gives the false impression they are equivalent only because 5mm is close to 0.2" but not exactly. 5/25.4 = 0.19685“. 1/0.19685 = 5.08 turns per inch.
Cheers,
Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
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Re: Encoder Basics
Remember that the servo motor must drive your spindle at a 1:1 ratio...no belt reduction.
Milton in Collierville, TN
"Accuracy is the sum total of your compensating mistakes."
"Accuracy is the sum total of your compensating mistakes."
Re: Encoder Basics
Just to be pedantic here:tblough wrote:lead and pitch are the same. ...
Pitch is how far a screw advances in one turn.
- Lead is how far a screw advances in one turn.
- Pitch is the distance between successive thread crests.
- They are the same for a single-start thread (the vast majority of threads you will encounter).
- They are different for multi-start threads: lead = pitch * number of starts.
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Re: Encoder Basics
Thanks tb, I appreciate the clarification. Also with regard to encoders, through some additional reading I found a diagram via Dynapar as being a helpful tool for those less familiar, like myself, to delineate the semantics of encoder classification.
http://www.dynapar.com/uploadedFiles/_S ... _29_13.pdf
To the experts, please confirm or correct my assertation with regard to the correct encoder type.
http://www.dynapar.com/uploadedFiles/_S ... _29_13.pdf
To the experts, please confirm or correct my assertation with regard to the correct encoder type.
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Re: Encoder Basics
Is there any way to use an encoder that does not make the individual A- B- and Z- available but uses a common instead?
This is the specsheet.
https://docs-emea.rs-online.com/webdocs ... e8dd0d.pdf
Thanks
This is the specsheet.
https://docs-emea.rs-online.com/webdocs ... e8dd0d.pdf
Thanks
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Re: Encoder Basics
Probably doesnt matter, it has too low res anyways to be any good it seems.
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Re: Encoder Basics
Chaz, check this out: https://cnc4pc.com/differential-line-driver.html.