Mitsubishi Electronics QD75D, QD75P 9.2.9 4-axis fixed-feed control (interpolation)

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
9.2.9 4-axis fixed-feed control (interpolation)
In "4-axis fixed-feed control" ("Da.2 Control s ystem" = fixed-feed 4), four motors are
used to carry out fixed-feed control in a linear path while carrying ou t interpolation for
the axis directions set in each axis.
In fixed-feed control, any remainder of the m ovement amount designated in the
positioning data is rounded down if less t han that required for control accuracy to
output the same amount of pulses. (The remaind er of the movement amount with an
accuracy below the control accuracy does no t affect the regular controls.)
(Refer to Section 9.1.6 "Interpolation control" for details on in terpolation control.)
Operation chart
In incremental system 4-axis fixed-feed control, the addresses ( Md.20 Current
feed value) of the current stop position (start addresses) of ever y axes are set to
"0". Linear interpolation positioning is then carried out from that pos ition 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.
Restrictions
(1) An axis error "Continuous path control not possible (error code: 516) " will
occur and the operation cannot start if "continuous path control" i s 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 system" 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 operat ion pattern of
positioning data No. 1 is "continuous path control", fixed-feed cont rol cannot
be set in positioning data No. 2.) An axis error "Continuous path c ontrol not
possible (error code: 516)" will occur and the machine will carry out a
deceleration stop if this type of setting is carried out.