
B-70255EN/01 10.REPLACEMENT PROCEDURES
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(1) Replacing the power supply
1) Turn off the power to the laser oscillator, then drain the
cooling water.
2) Remove the following water joints, power cables, and
signal cables:
See Fig. 10.2 (a).
- Water joint B
- XT21(200VAC)
- XT22(Output terminal)
- CP51
- CP73
- Ground cable
3) Remove the bolts securing the power supply, then remove
the power supply. If it proves difficult to pull out the power
supply, slightly shift it to the right or left, then retry.
4) Once the power supply has been replaced, tighten the bolts,
then connect the water joints, power cables, and signal
cables correctly.
The new power supply must be adjusted before it can be used.
(2) Checking for and replacing a damaged high-speed diode or FET
module PCB
(a) Preparation
1) Turn off the power to the CNC, then turn off the
power to the laser oscillator.
2) Remove the top cover of the laser power supply from
inside the oscillator.
(See Fig. 10.2 (a). To remove the top cover, remove
the screw indicated by A.)
3) Once the top cover has been removed, two FET
module PCBs (in the figure 10.2 (b)) and two diode
units appear.
(b) Checking for and replacing a damaged high-speed diode
1) To check whether a diode is damaged, measure the
resistance between the anode and cathode of each of
the diodes in the diode unit, by using a multimeter. A
resistance of less than 10W indicates that the diode is
damaged. (a normal diode will have a resistance of
about 3MW to 10MW.)
When measuring the diode resistance, apply the
positive probe of the multimeter to the cathode of the
diode, and apply the negative probe to the anode.
2) Remove the screw connecting the damaged diode and
the plate, then remove the diode fixing screw. See Fig.
10.2(c).
3) Install a normal diode, paying attention to its polarity,
then screw the plate firmly. This completes the
replacement work.
(c) Checking for and replacing a damaged FET module PCB
(See Fig. 10.2 (b).)