
B–70115EN/03
10. REPLACEMENT PROCEDURES
282
Figs. 10.2 (a) to (l) show the laser power supply. Replace the laser power
supply as described below.
(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). S Water joint A
S Water joint B
S TL17 or XT21
S TL18 or XT22
S CP51
S CP73
S 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.
Mount the cover for TL18 or XT22. 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
1) Preparation
1. Turn off the power to the CNC, then turn off the power to the
laser oscillator. In addition, open the main circuit breaker for
the laser oscillator.
2. Remove the top cover of the laser power supply from inside the
oscillator. (See Fig. 10.2 (b) and (h). To remove the top cover,
remove the screw indicated by A.)
3. Once the top cover has been removed in case of 6 kW power
supply, eight FET module PCBs (A in the figure 10.2 (c), (d))
and two diode units (B and C) appear. In case of 9 kW power
supply, two FET module PCBs (in the figure 10.2 (i), (j)) and
two diode units appear.
2) Checking for and replacing a damaged high–speed diode (See Fig.
10.2 (e), (f), (i) and (k).)
1. To check whether a diode is damaged, measure the resistance
between the anode and cathode of each of the twelve 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 3 MW to 10 MW.)
CAUTION
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.
10.2
REPLACING THE
LASER POWER
SUPPLY