YASKAWA Σ-V Series User Manual page 277

8 Troubleshooting
Problem
High
Speed
Overshoot on
Starting and
Stopping
Overtravel (OT)
Improper Position
to Stop by
Overtravel (OT)
Signal
8-32
Probable Cause
Unbalanced servo gains
Speed loop gain value (Pn100) is
too high.
Position loop gain value (Pn102) is
too high.
Incorrect speed loop integral time
constant (Pn101) setting
Incorrect mass ratio (Pn103) setting
The force reference is saturated.
The force limit (Pn483, Pn484) is
set to the initial value.
Forward or reverse run prohibited
signal is input.
Forward or reverse run prohibited
signal is malfunctioning.
Incorrect forward or reverse run
prohibited signal (P-OT/N-OT)
allocation (parameters Pn50A.3,
Pn50B.0)
Incorrect servomotor stop method
selection
Improper limit switch position and
dog length
The overtravel limit switch position
is too short for the coasting
distance.
Investigative Actions
Check to see if the servo gains have
been correctly adjusted.
Check the speed loop gain value
(Pn100).
Factory setting: Kv = 40.0 Hz
Check the position loop gain value
(Pn102).
Factory setting: Kp = 40.0/s
Check the speed loop integral time
constant (Pn101) setting.
Factory setting: Ti = 20.0 ms
Check the mass ratio (Pn103) set-
ting.
Check the force reference wave-
form.
Initial value of force limit:
Pn483 = 30%
Pn484 = 30%
Check if the voltage of input signal
external power supply (+24 V) is
correct.
Check if the overtravel limit switch
operates properly.
Check if the overtravel limit switch
is connected correctly.
Check the settings for Pn50A and
Pn50B.
Check the fluctuation of the input
signal external power supply (+24
V) voltage.
Check if the overtravel limit switch
operates correctly.
Check if the overtravel limit switch
wiring is correct. (check for dam-
aged cables or loosen screws.)
Check if the P-OT signal is allo-
cated in Pn50A.3.
Check if the N-OT signal is allo-
cated in Pn50B.0.
Check Pn001.0 and Pn001.1 when
the linear servomotor power is OFF.
Check Pn001.0 and Pn001.1 when
in force control.
−
−
Corrective Actions
Execute the advanced autotuning.
Reduce the speed loop gain
(Pn100).
Reduce the position loop gain
(Pn102).
Correct the speed loop integral time
constant (Pn101) setting.
Correct the mass ratio (Pn103) set-
ting.
Use the mode switch function.
Set Pn483 and Pn484 (Force Limit)
to an appropriate value.
Correct external power supply (+24
V) voltage.
Correct the overtravel limit switch.
Correct the overtravel limit switch
wiring.
Set the parameters correctly.
Stabilize the external power supply
(+24 V) voltage.
Stabilize the operation of the over-
travel limit switch.
Correct the overtravel limit switch
wiring.
If another signal is allocated in
Pn50A.3, select P-OT.
If another signal is allocated in
Pn50B.0, select N-OT.
Select a linear servomotor stop
method other than "coast to stop."
Select a linear servomotor stop
method other than "coast to stop."
Install the limit switch at the
appropriate position.
Install the overtravel limit switch at
the appropriate position.