
B-70255EN/01 6.TROUBLESHOOTING
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Cause of trouble Solution
2 Gas leakage from
piping
1)Check whether any component joints of the gas
circulating system are loose. If a loose joint is found,
tighten the joint firmly.
2)Check whether any components of the gas
circulating system are cracked. If a cracked
component is found, replace that component.
3)Check whether there is any hole in a discharge
tube. If a hole is found in a discharge tube, replace
the discharge tube.
3 Anomaly of supply
laser gas pressure
Adjust the secondary pressure at the regulator on the
gas cylinder so that the pressure of laser gas supplied
to the laser oscillator is 0.1 to 0.2 MPa (rating) as
measured at the entry of the oscillator. If the distance
between the gas cylinder and the oscillator is larger
than 5 m, it is necessary to set the pressure slightly
higher.
4 Anomaly of IF PCB
(A16B-2100-0141)
Measure the pressure monitor voltage (about 0 V to 9
V at the LTP test terminal) and command voltage
(about 5 V to 10 V at the GPC test terminal) being
output by the IF PCB. If a measured voltage is
abnormal, replace the IF PCB.
5 Anomaly of
pressure sensor
If the pressure indication (DGN 905) varies
significantly at irregular intervals, the pressure sensor
is faulty. Replace the sensor.
6 Anomaly of
pressure control
valve
If the above checks do not reveal any abnormality,
replace the pressure control valve.
ALM No.4082
Anomaly of pressure sensor
This alarm appears when the signal of the pressure sensor used
for pressure control detector vanishes.
Alarm output condition
This alarm is issued when the actual gas pressure lowers to 0 twice
successively during the time from RUN-ON until RUN-OFF.
Related parameters
DGN.905 Actual gas pressure
Cause of trouble Solution
1 Open or poor contact
in connection cable
between pressure
sensor and IF PCB
Check the cable connection. If the connection is
abnormal, replace the cable.
2 Anomaly of IF PCB
(A16B-2100-0141)
If a signal is received from the pressure sensor, but
there is no output from the IF PCB, the IF PCB is
faulty. Replace the IF PCB.
3 Anomaly of pressure
sensor
If the power supply (+15 V) for the pressure sensor
is normal, but there is no output, the pressure
sensor is faulty. Replace the pressure sensor.