Mitsubishi Electric MDS-B-SPJ2 Series Specification Manual page 133

(3) The stop position deviates.
Cause
Machine factor
Noise
(4) The spindle vibrates when stopped.
Cause
The parameter
setting is incorrect.
Orientation
adjustment
(5) An orientation completed signal is not output.
Cause
Refer to item (1) "Orientation is not carried out".
The machine load
is heavy
8. Adjustment Procedure
Investigation items
The stop position does not
deviate on the encoder axis.
• The deceleration ratio
between the spindle and
encoder is not 1:1 or 1: 2.
The position shift changed to
2048 at a 1:2 deceleration
ratio between the spindle and
encoder. (Deviation on the
encoder axis.)
There is a break in the
encoder cable.
Investigation items
The gear ratio parameters
GRA1 to 4 and GRB1 to 4 are
incorrect.
The vibration frequency is
several Hz.
The vibration frequency is
10Hz or more.
Investigation items
The in-position (parameter
OINP ) value is too small.
An orientation completed
signal is output by changing
the control during orientation
to PI control.
Remedy
There is backlash,
slippage, etc., between
the spindle and encoder.
Set the deceleration ratio
to 1:1 or 1:2.
The position does not
change because the
spindle rotates once at
2048 in this case.
(However, the position
changes on the encoder
axis.)
Use one encoder cable.
Remedy
Correctly set the gear
ratio parameters.
Lower the position loop
gain PGM and PGE .
Lower the speed loop
gain VGOP and
VGOI during
orientation.
Remedy
Reconsider the in-position
range.
(Parameter x OINP )
Reconsider the speed
loop gain during
orientation (parameters
VGOP and VGOI ).
8 − 14
Remarks
Remarks
Remarks
This may also
apply if hunting
occurs at the
stop point.