Mitsubishi Electric MELSEC-Q Series User Manual page 149

([Pr.11] Backlash compensation amount)
0 
([Pr.3] Movement amount per rotation (AL))
(Maximum motor speed (r/min) )
A 
[Pr.11] Backlash compensation amount
The error that occurs due to backlash when moving the machine via gears can be
compensated.
(When the backlash compensation amount is set, commands equivalent to the
compensation amount will be output each time the direction changes during
positioning.)
1) The backlash compensation is valid after machine HPR. Thus, if the backlash
compensation amount is set or changed, always carry out machine HPR once.
2) "[Pr.2] Number of pulses per rotation (AP)", "[Pr.3] Movement amount per
rotation (AL)", "[Pr.4] Unit magnification (AM)" and "[Pr.11] Backlash
compensation amount" which satisfies the following (1) can be set up.
([Pr.2] Number of pulses per rotation (AP))
The error "Backlash compensation amount error" (error code: 920) occurs
when the setting is outside the range of the calculation result of (1).
A servo alarm (error code: 2031, 2035, etc.) may occur by kinds of servo
amplifier (servomotor), load inertia moment and the amount of command of a
cycle time (Simple Motion module) even if the setting is within the calculation
result of (1).
Reduce the setting value of "[Pr.11] Backlash compensation amount" or
increase the operation cycle by "[Pr.96] Operation cycle setting" if a servo
alarm occurs. Use the value of the following (2) as a measure that a servo
alarm does not occur.
1.2
60(s)
Chapter 5 Data Used for Positioning Control
HPR direction
Pr.44
([Pr.4] Unit magnification (AM))
(Encoder resolution (PLS/r) )
1000 (ms)
5 - 29
Workpiece
(moving body)
Worm gear
Backlash
(compensation amount)
( = A)  4194303 (PLS) ....(1)
(round down after decimal point)
(Operation cycle (ms))
(PLS) ....(2)