Omron R88D-UA Manual page 24

Connection to Position Control Unit
The Next Positioning Operation is Not Performed.
The Rising Edge of the Positioning Completion Signal is Not Detected.
• The next positioning step will be usually taken after the confirmation of the present positioning completion
signal.
• Therefore, if the completion of positioning is not confirmed, the Position Control Unit cannot take the next
stop and the operation is interrupted.
Probable cause
The positioning time is short
compared with the cycle time.
The positioning completion signal
is not output or it takes too long to
output the positioning completion
signal.
Deviation Counter Overflow Results
• The deviation counter is in control of the difference between the command position and actual motor posi-
tion.
• If the difference between the command position and motor position is too large, the deviation counter will
overflow and a deviation counter error or deviation counter overflow will result.
• The error results if the motor cannot carry out the command.
Probable cause
The gains are too low.
The gains are too high.
The speed command value is too
large.
The load is too heavy.
Acceleration/Deceleration time is
too short.
2-8
Item to check
• The positioning operation has
completed normally and the
positioning completion signal
has been output. The PC can-
not, however, check that the
completion signal has been
turned OFF.
• The positioning operation is per-
formed normally but the position-
ing completion signal is not out-
put.
• Incorrect gain adjustment has
been made and the gains are
too low.
• The zero adjustment of the
speed command is incorrect and
the value of the deviation count-
er is large when the Position
Control Unit stops.
• The set value of positioning
completion width is too small.
Item to check
• The motor response is slow.
(Use speed monitor.)
• Overshooting is resulting.
(Use speed monitor.)
• The speed command voltage is
set to a value exceeding 10 V.
• The Servo Driver is generating
its maximum torque at decelera-
tion or acceleration time. (Use
current monitor.)
Chapter 2
Countermeasure
• Use the positioning completion
dwell timer and delay the output
timing of the positioning comple-
tion signal.
• Use the M code and confirm that
the completion signal has been
turned OFF by checking status
changes in the M code.
• Adjust the gains.
• Adjust the zero adjustment of the
speed command.
• Increase the set value of posi-
tioning completion width.
Countermeasure
• Adjust the gains.
(Increase the gains.)
• Adjust the gains.
(Decrease the gains.)
• Reset the value to 10 V or less.
• Use parameters, such as a
speed command scale, and de-
crease the command voltage
that is used for obtaining the
rated rotation speed.
• Decrease the load.
• Increase acceleration/decelera-
tion time.