Panasonic minas a series Operating Manual page 77

Troubleshooting
Category
Velocity commands contain noises.
Wiring
Improper offset
Velocity commands contain noises.
Positioning accuracy is bad.
Category
System Position commands (amount of com-
mand pulses) are not correct.
Reading of in-position signals occurs
at the edge.
The form and width of the command
pulses deviate from the specified val-
ues.
Adjustment The position loop gain is too small.
The setting of in-position detection
Parameter
range (Pr60) is too large.
The command pulse frequency ex-
ceeds 500 kpps.
The scale is not appropriate.
Causes
Use shielded cables for connection to CN I/F. Power and sig-
nal cables should be separated by at least 30 cm and put in
duct.
Measure the voltage between CN I/F pins 14 and 15 (veloc-
ity command inputs) using a circuit tester and/or oscilloscope.
Adjust the value of Pr52 so that the motor can stop.
Use shielded cables for connection to CN I/F. Power and sig-
nal cables should be separated by at least 30 cm and put in
duct.
Causes
Count the number of feedback pulses while repeating to travel
back and forth within a fixed distance. If the number of feed-
back pulses varies, adjust the controller. Take measures to
reduce the noise on the command pulse.
Use the check pin (IM), to monitor the position error when
the in-position signals are received. Read the in-position sig-
nals at a mid point on the time span, not at the edge.
If the command pulses are deformed or narrowed, adjust the
pulse generation circuit. Take measures to reduce the noise
on the command pulse.
Check the amount of position error in the monitor mode. In-
crease the value of Pr10 to the extent that no oscillation oc-
curs.
Decease the value of Pr60 (in-position range) to the extent
that the in-position signals do not chatter.
Decrease the command pulse frequency. Change the values
of Pr46 through Pr4B (numerator of 1st to 4th command
scale).
Check the repetition accuracy. If repeated without fluctua-
tion, increase the capacity of the motor and driver.
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Countermeasures
Countermeasures