
6.TROUBLESHOOTING B-70255EN/01
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ALM No.4085
Decrease of laser output power
This alarm appears when the laser output power decreases and
takes an abnormally higher calibration coefficient.
Alarm output condition
This alarm is
issued when the power compensation coefficient exceeds the power
compensation limit during execution of power compensation.
Power compensation coefficient = (Pc/Pa) x 1024
Pc: Parameter No. 15200 or 15201
Pa: Actual laser output
Related parameters
PRM.15200
Power compensation command output for a half of the discharge tubes
PRM.15201
Power compensation command output for all discharge tubes
PRM.15203 Power compensation limit
PRM.15204 Power compensation coefficient
Cause of trouble Solution
1 An optical part in the laser
resonator is out of position.
Align the laser resonator.
2 An optical part in the laser
resonator is dirty.
Clean or replace the optical part.
3 The supplied laser gas is
not the one 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%.
4 Cooling water temperature
out of specified range
Check whether the temperature of cooling
water falls within the range of 20 to 30°C.
5 Laser oscillator ambient
temperature out of specified
range
Check whether the ambient temperature falls
within the range of 5 to 30
°C.
ALM No.4087
Shutter temperature abnormal
This alarm is issued when the temperature of the shutter mirror
exceeds a preset maximum (80°C)
Alarm output condition
This alarm is issued when the shutter temperature signal becomes 0 in
LRDY or a later step.
Shutter temperature signal
SHT (bit 6 at address 01H of DI of the laser interface)
Related parameters
PRM.961#6 *SHT Shutter temperature sensor
The table below lists the causes of faults and the corresponding
countermeasures.