Mitsubishi Electric MELSEC Q Series, User Manual

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Chapter 9 Major Positioning Control
9.2.9 4-axis fixed-feed control (interpolation)
In "4-axis fixed-feed control" ("[Da.2] Control method" = fixed-feed 4), four motors are
used to carry out fixed-feed control in a linear path while carrying out interpolation for
the axis directions set in each axis.
In fixed-feed control, any remainder of below control accuracy is rounded down to
convert the movement amount designated in the positioning data into the command
value to servo amplifier.
(Refer to Section 9.1.6 "Interpolation control" for details on interpolation control.)
Operation chart
In incremental system 4-axis fixed-feed control, the addresses ([Md.20] Feed
current value) of the current stop position (start addresses) of every axes are set
to "0". Linear interpolation positioning is then carried out from that position to a
position at the end of the movement amount set in "[Da.6] Positioning
address/movement amount". The movement direction is determined by the sign of
the movement amount.
• Positive movement amount .............. Positioning control to forward direction
(Address increase direction)
• Negative movement amount ............. Positioning control to reverse direction
(Address decrease direction)
Restrictions
(1) The error "Continuous path control not possible" (error code: 516) will occur
and the operation cannot start if "continuous path control" is set in "[Da.1]
Operation pattern". ("Continuous path control" cannot be set in fixed-feed
control.)
(2) "Fixed-feed" cannot be set in "[Da.2] Control method" in the positioning data
when "continuous path control" has been set in "[Da.1] Operation pattern" of
the immediately prior positioning data. (For example, if the operation pattern of
positioning data No. 1 is "continuous path control", fixed-feed control cannot
be set in positioning data No. 2.) The error "Continuous path control not
possible" (error code: 516) will occur and the machine will carry out a
deceleration stop if this type of setting is carried out.
(3) Set "1: Reference axis speed" in "[Pr.20] Interpolation speed designation
method". The error "Interpolation mode error" (error code: 523) will occur and
the operation cannot start if "0: Composite speed" is set.