Spindle Servo encoder feedback

[mick41zxr]

Hi,
I am bench testing a spindle servo in speed mode. It is 2.2kw 8000rpm with 1000 line encode feedback.
Able to run the spindle through full range without the encoder connected to Acorn (via pulse feedback from driver).
spindle is responsive & stable. However when I connect encoder Acorn faults out on encode quadrature error.
Spinning encode by hand Acorn reads the signal & appears to match speed displayed on driver.
Any help appreciated.
Thanks,
Michael

report_F045DA486298-0813181135_2018-09-29_18-50-47.zip

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[cnckeith]

Please show us a detailed picture of the encoder cable and describe the gauge and type of cable being used along with the drain and shield connections at each end.

Quadrature error equals noise in the line 99% of the time.

[mick41zxr]

Thanks Keith,
Cable was made from stranded Cat5 that was at hand when testing.
Would you ground the shield at drive or Acorn?
I will make a better one & report back.
Regards,
Michael

[martyscncgarage]

You may not have the cable wired right either.
Make a wiring diagram of how you wired both ends of your cable and supply documentation to the encoder.

The ethernet cable is OK PROVIDED You used a SHIELDED, STRANDED cable. You solder the shield drain wire to the shell of the DB9 connector.

Marty

[mick41zxr]

Thanks Marty,
Cable tested out ok on the meter, but Keith was on the money.
Modified an existing shielded serial cable i had laying around & encoder worked perfectly.
Regards,
Michael

[martyscncgarage]

Perfect, noise is the number one culprit of encoder issues, followed by miswiring. (assuming the correct line driver/differential encoder was chosen to begin with)

Glad you are on your way.
Post a video in Success Stories of your machine!