
7.UNITS B-70265EN/02
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(4) After replacing the power supply unit with a new one, tighten the
mounting bolts, and attach the water fittings and the power and
signal cables.
When attaching the water fittings, loosen portion A shown in the
figure, determine the orientation of the fittings, tighten portion A
by your fingers, then additionally tighten the portion by 60° with
a wrench.
(5) Then, make power supply adjustments. (See Subsection 7.2.2.)
7.2.1.2 Replacing a high-speed diode
(1) Turn off the power to the CNC, and turn off the main circuit
breaker of the oscillator.
(2) Remove the water fittings, and power and signal cables.
(3) Remove the mounting screws on the top plate of the laser power
supply unit, and remove the top plate.
(4) As shown in Fig. 7.2.1, you can see the two FET module PCBs
and the diode unit.
(5) Check for a damaged element, and replace it.
(a) Checking the high-speed diode
Measure the resistance across the anode and cathode of the
diode with a tester. If the resistance is several ohms, the
diode is regarded as being damaged. (The resistance of a
normal diode is several mega-ohms.)
To measure the resistance of a diode, touch the positive
probe of the tester to the cathode of the diode, and touch the
negative probe to the anode.
(b) Remove the damaged diode, and replace it.
(6) After diode replacement, power supply adjustment is
unnecessary.