Conversion of Starturn 4 to NextStep to run VRTurn, Encoder?

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JSKRABA
CNC Apprentice
CNC Apprentice
Posts: 50
Joined: Sat 11 Nov , 2006 19:17 pm

Conversion of Starturn 4 to NextStep to run VRTurn, Encoder?

Post by JSKRABA » Mon 02 May , 2016 20:31 pm

I am converting a mechanically very nice Starturn 4 to run with NexStep board and its going very well.
Have fitted homing /limit switches, Spindle works fine controlled by the software, Steppers are fine and work well.

HOWEVER

I am trying to get the old twin output encoder to work.
I understand the wiring, 5V in Ground, and 50 Pulses/rev out on one channel and 1 pulse/rev on the other.
I have set the encoder settings to 50 pulses per rev. And on running I get a response for the speed but its strange
It goes from 0 - 53 at 2500rpm, rather than 0-2500 as it should, it is proportional ie 23 at 1000rpm. I do not understand this.

I have checked with a scope and it does produce a single pulse of +5v per rev and 50 per rev on other channel
I am assuming that it is the 1 per rev that is used for RPM calculations and the 50 is use for threading (Please confirm)

I have not tested threading yet as I thought i would get the RPM sorted first.
am I missing something, should it be at +5v and drop to 0V to recognise the pulse?
What should the wireing be? Can it be used at all with NextStep and VRTurn?

Assistance appreaciated
Regards

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