Replacing the pilot arc igbt – Hypertherm Powermax125 Service Manua User Manual
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Powermax125 Service Manual 808070
211
9 – Power Supply Component Replacement
Replacing the pilot arc IGBT
1. Complete the following procedures:
a. See Disconnect the power and gas supply on page 166.
b. See Remove the power supply cover on page 172.
c. See Remove the component barrier on page 173.
d. See Remove the DSP board on page 203.
e. See Remove the power board on page 205.
2. Remove the 2 mounting screws from the pilot arc IGBT. See Figure 76 on page 215.
3. Remove the pilot arc IGBT with its red and black wire pair from the heatsink.
4. Clean the area where the pilot arc IGBT was mounted, using isopropyl alcohol to remove the old thermal grease from
the heatsink.
5. Apply a 0.0762 mm (0.003 inch) layer of thermal grease, about the thickness of a sheet of paper, evenly to the pilot
arc IGBT mounting surface.
6. Mount the pilot arc IGBT to the heatsink by hand-tightening the 2 supplied mounting screws.
7. Step-torque the 2 mounting screws to the proper torque value as shown in Figure 76 on page 215.
8. Connect the supplied cable to the pilot arc IGBT terminals. The black wire connects to the top terminal (labeled “E2”
or “7”), and the red wire connects to the bottom terminal (labeled “G2” or “6”).
9. Complete the following procedures:
a. See Install the power board on page 206.
b. See Install the DSP board on page 203.
c. See Install the component barrier on page 173.
d. See Install the power supply cover on page 172.
e. Reconnect the power and gas supply.
Kit number
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