5.TROUBLESHOOTING B-70315EN/02
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ALM No.4076
LASER POWER DOWN
This alarm is issued if the monitored laser output is lower than
the specified laser output by at least the allowable value.
Alarm output condition
This alarm is issued when the actual laser output level is lower than the
average command power (power x duty) by more than the value set in
parameter No. 15271. Monitoring, however, is not performed for three
seconds after the beam is turned or after the output is changed.
Related parameters
PRM.15271 Allowable output drop value
Related data
DGN.906 Actual output
No. Cause of trouble Solution
1 Lack of output
from laser power
sensor unit
The thermocouple inside the power sensor unit may
be damaged, or there may be a poor terminal
connection. Measure the direct current resistance
between the terminals of the power sensor unit, and
check that the measured value falls within 100 to
500 ohms. If the measured value falls outside this
range, replace the power sensor unit.
2 Connecting
anomaly of the
cable of laser
power sensor unit.
Check whether the cable is securely connected to
the power sensor unit. If not, reattach the cable.
3 Anomaly of
intermediate PCB
B
(A16B-1600-0363)
If the above checks do not reveal any abnormality,
and there is no output from intermediate PCB B,
replace the PCB.
4 Decrease in actual
output level
1) Check whether the mirrors are dirty, degraded, or
damaged, and clean or replace faulty mirrors.
2) Align the mirrors.
3) Check whether the temperature of the cooling
water satisfies the setting, and adjust the
temperature.
4) Check for internal leakage due to a damaged
discharge tube or degraded O-ring, and replace
any faulty part.
5) Check for leakage in the gas circulating system
and for water leakage, and if any problem is
found, take appropriate action.
6) Check the frequency setting for the inverter.
7) Check the values set in PRM Nos. 15242 and
15243 against the corresponding values in the
parameter table attached to the unit.
8) Replace the laser gas with one having the
specified composition.