Mitsubishi Electronics QD75D, QD75P user manual 7 2-axis fixed-feed control interpolation

9MAJOR POSITIONING CONTROL

9.2.7 2-axis fixed-feed control (interpolation)

MELSEC-Q

In "2-axis fixed-feed control" ("

Da.2

Control system" = fixed-feed 2), two 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 the movement amount designated in the positioning data is rounded down if less than that required for control accuracy to output the same amount of pulses. (The remainder of the movement amount with an accuracy below the control accuracy does not affect the regular controls.)

(Refer to Section 9.1.6 "Interpolation control" for details on interpolation control.)

Operation chart

In incremental system 2-axis fixed-feed control, the addresses ( Md.20

Current

feed value) of the current stop position (start addresses) of both 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.

Y axis

Designated movement amount

" Md. 20 Current feed value" of each axis is set to "0" at the positioning start

(0,0)

(0,0)

(0,0)

X axis

Designated 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" is set in

"

Da.1

Operation pattern". ("Continuous path control" cannot be set in fixed-

feed control.)

(2)If the movement amount of each axis exceeds "1073741824 (=230)" when "0:

Composite speed" is set in " Interpolation speed designation method", the "Outside linear movement amount range error (error code: 504)" occurs at a positioning start and positioning cannot be started. (The maximum movement amount that can be set in " Da.6 Positioning address/movement amount" is "1073741824 (= 230)".

(3)"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 operation pattern of positioning data No. 1 is "continuous path control", fixed-feed control cannot be set in positioning data No. 2.) An axis 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.

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