Omron OMNUC G User Manual page 394

8-3 Troubleshooting
Alarm
code
18
21
8
communications error
23 communications data
Deviation counter
24
8-9
Alarm Name
The regenerative energy exceeded the
capacity of the regeneration resistor.
1 The converter voltage was
increased by regenerative energy
during deceleration due to a large
load inertia. The voltage was
further increased due to insufficient
energy absorption of the
regeneration resistance.
2 Because the Servomotor's rotation
speed is too high, regenerative
Regeneration
energy cannot be fully absorbed
overload
within the specified deceleration
time.
3 The operating limit of the External
Regeneration Resistor is limited to
10%.
Communications between the encoder
and the Servo Drive failed for a
Encoder specified number of times, thereby
activating the error detection function.
(No response to request from the
Servo Drive.)
Communications error occurred for the
data from the encoder. Mainly a data
error due to noise. The encoder line is
connected, but the communications
data is erroneous.
Encoder
error
The number of position deviation
pulses exceeded the Deviation
Counter Overflow Level (Pn209).
1 The Servomotor operation is not
following the commands.
2 The Deviation Counter Overflow
Level (Pn209) is set too low.
overflow
Calculate the deviation counter
value based on the command
speed and the position loop gain.
Cause
Check the regeneration resistance
load ratio. Continuous regenerative
braking is not acceptable.
1 Check the operation pattern (speed
monitor). Check the regeneration
resistance load ratio and the over-
regeneration warning display.
Increase the capacity of the
Servomotor and the Servo Drive to
slow down the deceleration time.
Use an External Regeneration
Resistor.
2 Check the operation pattern (speed
monitor). Check the regeneration
resistance load ratio and the over-
regeneration warning display.
Increase the capacity of the
Servomotor and the Servo Drive to
slow down the deceleration time.
Lower the Servomotor rotation
speed. Use an External
Regeneration Resistor.
3 Set Pn06C to 2.
Check that the encoder line is properly
connected.
Check that there is no damage to the
encoder due to incorrect connections.
Replace the Servomotor and check
again.
Check that the encoder power supply
voltage is within the range of 4.75 to
5.25 VDC. (If the encoder line is
long.)
If the Servomotor line and the
encoder line are bound together,
separate them.
Check that the shield is connected to
FG (frame ground), and that FG is
grounded.
Attach a ferrite core to the encoder
cable. Attach a radio noise filter to the
power cable.
1 Use the speed monitor and torque
monitor to check that the
Servomotor is operating as
commanded. Check that torque is
not saturated. Check that the No. 1
Torque Limit (Pn05E) and the No. 2
Torque Limit (Pn05F) are not too
small.
Check by readjusting the gain,
increasing the acceleration /
deceleration times, and lowering
the speed with the reduced load.
2 Increase the setting for Pn209.
Countermeasure