Initial resistance check, Powermax30 – Hypertherm Powermax30 Service Manual User Manual
Page 46

MAINTENANCE
powermax30
Service Manual
3-7
74.5 kΩ
3. Check the resistance from the input leads to ground to verify that it reads as open.
Note:
With the power disconnected and the ON/OFF switch (S1) set to OFF (O), all circuits should read
as open.
The electrical value shown is ±25%.
If no problems were found during the visual inspection or the initial resistance check, and the power supply still
does not operate correctly, see the
Note:
Troubleshooting guide provides most probable causes and solutions. Study the system wiring
diagram and understand the theory of operation before troubleshooting. Before purchasing any major
replacement component, verify the problem with Hypertherm Technical Service or the nearest
Hypertherm repair facility.
Initial resistance check
All resistance values must be taken with the power cord disconnected and all internal power supply wires attached.
Perform the steps in
Internal inspection before continuing in this section.
• If resistance values are not close (±25%) to the values given in this section, isolate the problem by
removing wires attached to the resistance check points or component until the problem is found.
• After the problem has been located and repaired, refer to the
Sequence of operation flow diagram in this
section to test the power supply for proper operation.
1. With the power disconnected, set the ON/OFF switch (S1) to ON (I).
2. Check the resistance across the input leads.
Black (CSA), brown (CE)