
B-70255EN/01 6.TROUBLESHOOTING
- 77 -
Cause of trouble Solution
1 Contamination of shutter mirror Clean the shutter mirror. If this alarm
recurs after the shutter mirror is
cleaned, replace the mirror.
2 Anomaly of temperature sensor Replace the temperature sensor.
3 Temperature sensor cable
broken
Replace the cable.
4 Relay PCB (A16B-1600-0361) or
IF PCB(A16B-2100-0141) is
faulty.
Replace the faulty PCB.
5 Anomaly of PCB connection
cables
Check the connection of each cable.
ALM No.4088
Discharge tube voltage drop
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 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.
Alarm output condition
During beam output, this alarm is issued when the actual laser output is in
one of the following conditions:
(1) Immediately before LSTR, the RF voltage of the power supply of the
discharge tube having the smallest number among the selected
discharge tubes is compared with the parameter setting (parameter No.
15270 to 15272). If the discharge tube voltage is lower than the
parameter setting, this alarm is issued. If the discharge tube voltage is
not lower than the parameter setting, the discharge tube voltage is set in
parameter No. 15270.
(2) When external power control is not performed during power
compensation or during LSTR, the discharge tube voltage is compared
with parameter setting (parameter No. 15270 to 15272). If the discharge
tube voltage is once lower than the parameter setting, a comparison is
made again 1024 msec later. If the second comparison also shows that
the discharge tube voltage is lower than the parameter setting, this
alarm is issued.
Related parameters
DGN.909-924 Discharge tube voltage and current
PRM.15270 Discharge tube voltage in normal condition
PRM.15271 Allowable discharge tube voltage drop
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% (volume ratio) with a
composition ratio accuracy of ±5%.
2 Anomaly of
discharge tube
voltage detection
system
If discharge is performed, but the monitored
discharge tube voltage is extremely low, replace the
matching box.
3 Degradation of Check whether the turbo blower and high-frequency