Motion complete trippoint, Using an encoder with stepper motors – Yaskawa SMC–4000 User Manual

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SMC–4000 User Manual

Motion Complete Trippoint

When used is stepper mode, the MC command will hold up execution of the proceeding commands until
the controller has generated the same number of steps out of the step count register as specified in the
commanded position. The MC trippoint (Motion Complete) is generally more useful than AM trippoint
(After Motion) since the step pulses can be delayed from the commanded position due to stepper motor
smoothing.

Using an Encoder with Stepper Motors

An encoder may be used on a stepper motor to check the actual motor position with the commanded
position. If an encoder is used, it must be connected to the main encoder input.

NOTE: The auxiliary encoder is not available while operating with stepper motors. The position of the
encoder can be interrogated by using the command, TP. The position value can be defined by using the
command, DE.

NOTE: Closed loop operation with a stepper motor is not possible.

Command Summary - Stepper Motor Operation

Operand Summary - Stepper Motor Operation

Command

Description

DE

Define Encoder Position (When using an encoder)

DP

Define Reference Position and Step Count Register

IT

Motion Profile Smoothing - Independent Time Constant

KS

Stepper Motor Smoothing

MT

Motor Type (2, -2, 2.5, or -2.5 for stepper motors)

RP

Report Commanded Position

TD

Report number of step pulses generated by controller

TP

Tell Position of Encoder

Operand

Description

_DEa

Contains the value of the step count register for the “a” axis

_DPa

Contains the value of the main encoder for the “a” axis

_ITa

Contains the value of the Independent Time constant for the “a” axis

_KSa

Contains the value of the Stepper Motor Smoothing Constant for the “a” axis

_MTn

Contains the motor type value for the “a” axis

_RPn

Contains the commanded position generated by the profiler for the “a” axis

_TDa

Contains the value of the step count register for the “a” axis

_TPa

Contains the value of the main encoder for the “a” axis

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