Specifications

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<Method of compensating the mechanical system errors>
When the positioning is carried out by the set "movement amount per pulse", an error
sometimes occurs between the command movement amount and the actual
movement amount.
The QD75 can compensate this error by adjusting the values in No. of pulses per
rotation, movement amount per rotation and unit magnification.
The method of compensating the errors using the QD75 is shown below.
(1) Set the command movement amount (mm) and carry out positioning.
(2) After positioning, measure the actual movement amount.
(3) With the obtained command and actual movement amount, how much
compensation is needed for [No. of pulses per rotation] and [Movement amount
per rotation] can be calculated as follows:
(a) Movement amount per pulse (mm/pulse) to command movement amount
(mm)
No. of pulses per rotation (AP)
Movement amount per rotation (AL)
Unit magnification (Am)
Movement amount per pulse=
(b) No. of pulses required
Movement amount per rotation
Command movement amount
(pulse)
No. of pulses re quire d=
(c) Apparent movement amount per pulse to actual movement amount (mm)
=
No. of pulses per rotation for compensation (AP')
Movement amount per rotation for compensation (AL')
Unit magnification (Am)
No. of pulses per rotation (AP)
Movement amount per rotation (AL)
Command movement amount
Actual movement amount
Unit magnification (Am)
In the upper formula, reduce the fraction of A
L
'
/A
P
'
to its lowest terms and
replace with this obtained value.