
B–70114EN/04
6. TROUBLESHOOTING
153
Shutter temperature abnormal
(Refer to bit 6 of DGN 961 [bit 2 of 841].)
This alarm is issued, if the temperature of the shutter mirror exceeds the
limit, which is 80°C for C1500B, C2000B, C2000C, C3000C, C3000D,
C4000A, or 90°C for C6000B.
No. Cause of trouble Solution
1 Contamination of shutter
mirror
Call the FANUC service center.
2 Temperature sensor abnor-
mal, or its cable broken
3 Intermediate PCB B abnor-
mal
4 Anomaly of the cables con-
necting each PCB
5 Shutter fan operation abnor-
mal
Discharge tube voltage drop (Refer to DGN 909 [861].)
This alarm is issued, if the voltage applied to the discharge tube drops
largely. More specific, the discharge tube voltage for reference discharge
is set up automatically to parameter No. 15270 [199] each time the RUN
button is pressed. This alarm is issued, if the automatically set discharge
tube voltage is lower than the discharge voltage specified at the previous
RUN time, by at least the amount specified in parameter No. 15272 [243].
No. Cause of trouble Solution
1 The laser gas composition
is not as specified.
Replace the laser gas with the specified
one, that is CO
2
:N
2
:He = 5:55:40% (vol-
ume ratio) with a composition ratio accu-
racy of "5%.
2 Gas leakage from the exter-
nal pipe
Check the pipe clamp for gas leakage.
3 Gas leakage from the oscil-
lator
Call the FANUC service center.
4 Laser power supply dis-
charge tube voltage detec-
tor abnormal
Alarm No. 4087 [687]
Alarm No. 4088 [688]