Hypertherm Powermax45 Service Manual - Manual (Page 125)

component replacement
powermax
45 Service Manual 6-21
Replace the power board (400 V Ce and 480 V CSA)
Before beginning this procedure, make sure you have the correct power board for your system. The kit number for a
400 V CE power board is 228260. The kit number for a 480 V CSA power board is 428078. These power boards have
a small slot immediately below the heat sink assembly screw hole and a single input bridge diode.
1. Turn OFF the power, disconnect the power cord, and disconnect the gas supply.
2. Use a #2 Phillips screwdriver to remove the 2 screws from the handle on the top of the power supply. Tip the end
panels back slightly so that you can get the edges of the handle out from underneath them. Lift the cover off the
power supply. Remove the Mylar barrier that protects the power board.
CAUTIoN
Static electricity can damage circuit boards. Use proper precautions when handling
printed circuit boards.
– Store PC boards in anti-static containers.
– Wear a grounded wrist strap when handling PC boards.
3. Detach the ribbon cable from J8 on the heat sink side of the power board. (See the illustrations following this
procedure for the location of the ribbon cable and the components listed in the steps that follow.)
4. Remove the connectors at J10, J12, and J22 on the heat sink side of the power board.
5. Remove the connectors at J4, J5, and J6 on the heat sink side of the power board.
6. Remove the wires for the transformers and inductors at J13, J14, J15, J16, J17, J18, J19, and J20.
7. Remove the work lead ring terminal from J21 and the 4 capacitor screws.
8. Remove the 3 retaining screws, the 4 resistor screws, and the 4 heat sink assembly screws.
9. If you have an older 400 V CE power board that has 2 input bridge diodes (and without the small slot below the
heat sink assembly screw hole), remove the 2 screws that attach the IGBTs and the 2 screws that attach the input
bridge diodes to the heat sink. There are holes in the power board to provide access to them.
If you have a newer 400 V CE or 480 V CSA power board that has a single input bridge diode (and has a small
slot below the heat sink assembly screw hole), remove the 2 screws that attach the IGBTs and the screw that
attaches the input bridge diode to the heat sink. There are holes in the power board to provide access to them.
10. Remove the screws at J1, J2, and J3 that secure the 3 white wires from the bottom of the ON/OFF switch to the
power board.
11. Stand up the unit again. Tuck out of the way all the wires that you detached.
12. Pull the board straight out from the power supply.
13. Before installing a new power board, clean the heat sink with isopropyl alcohol. Gently scrub away any residual
thermal compound, being careful not to scratch the heat sink. Wipe it with a clean cloth.