Mitsubishi Electronics QD75D, QD75P user manual Electronic gear function, Pr.2

12CONTROL SUB FUNCTIONS

12.3.2 Electronic gear function

MELSEC-Q

The "electronic gear function" adjusts the pulses calculated and output according to the parameters set in the QD75 with the actual machine movement amount.

The "electronic gear function" has the following three functions.

[A]During machine movement, the function increments in the QD75 values less than one pulse that could not be pulse output, and outputs the incremented amount of pulses when the total incremented value reached one pulse or more.

[B]When machine OPR is completed, current value changing is completed, speed control is started (except when current feed value change is present), or fixed-feed control is started, the function clears to "0" the cumulative values of less than one pulse which could not be output. (If the cumulative value is cleared, an error will occur by a cleared amount in the feed machine value. Control can be constantly carried out at the same machine movement amount, even when the fixed-feed control is continued.)

[C]The function compensates the mechanical system error of the command movement amount and actual movement amount by adjusting the "movement amount per pulse".

(The "movement amount per pulse" value is defined by "

Pr.2

No. of pulses

per rotation (Ap)", " Pr.3 Movement amount per rotation (Al)", and "

Unit magnification (Am)".)

The QD75 automatically carries out the processing for [A] and [B].

Pr.4

The details shown below explain about the "electronic gear function", including the method for compensating the error in [C] above, etc.

[1]Error compensation method

[2]Relation between the movement amount per pulse and speed

[3]Precautions during control

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