
3. TROUBLESHOOTING
B-65165E/02 TROUBLESHOOTING AND ACTION
- 137 -
3.3.4 Feedback Disconnected Alarm
(Alarm identification method)
#7 #6 #5 #4 #3 #2 #1 #0
<1> Alarm 1
OVL LVA OVC HCA HVA DCA FBA OFA
<2> Alarm 2 ALD EXP
<6> Alarm 6 SFA
FBA ALD EXP SFA Alarm description Action
1 1 1 0 Hard disconnection (separate phase A/B) 1
1 0 0 0 Soft disconnection (closed loop) 2
1 0 0 1 Soft disconnection (α pulse coder) 3
(Action)
Action 1: This alarm is issued when a separate phase A/B scale is
used. Check if the phase A/B detector is connected
correctly.
Action 2: This alarm is issued when the position feedback pulse
variation is small relative to the velocity feedback pulse
variation. This means that this alarm is not issued when a
semi-full is used. Check if the separate detector outputs
position feedback pulses correctly. If position feedback
pulses are output correctly, it is considered that the motor
alone is rotating in the reverse direction at the start of
machine operation because of a large backlash between the
motor position and scale position.
#7 #6 #5 #4 #3 #2 #1 #0
1808 8X03 TGAL
2003 1003
TGAL (#1) 1: Uses the parameter for the soft disconnection alarm
detection level.
1892 8X64 Soft disconnection alarm level
2064 1064
Standard setting 4: Alarm issued for a 1/8 rotation of the motor.
Increase this value.
Action 3: This alarm is issued when synchronization between the
absolute position data sent from the built-in pulse coder and
phase data is lost. Turn off the power to the CNC, then
detach the pulse coder cable then attach it again. If this
alarm is still issued, replace the pulse coder.