Warning, Service manual power board, Aintenance – Hypertherm Powermax900 Service Manual User Manual
Page 49: Power board test points
M
AINTENANCE
3-22
Service Manual
POWER BOARD
The power board contains part of a "soft start' or "in-rush" circuit, an over-voltage shut down circuit,
and the high-voltage power circuits for left and right inverters. Voltages can be taken at the rear of
the power PCB to check these functions.
WARNING
SHOCK HAZARD: The "E" terminals and J1 are accessible from the back
side of the power PCB. Use extreme caution when taking these readings.
Voltages up to 300 VDC are present at the rear of the power PCB.
The large electrolytic capacitors, (blue-cased cylinders) located on the
front side of the power PC board store large amounts of energy in the
form of electrical voltage. Even if the power is off, dangerous voltages
exist at the capacitor terminals on the PC board and on certain areas of
the PC board. Never discharge the capacitors with a screwdriver or other
implement... explosion, property damage and/or personal injury will
result.
Wait at least 5 minutes after turning the power supply off before handling
the PC board or capacitors. If questions or problems arise during
servicing, call Hypertherm Technical Services at 1-800-643-9878.
Use extreme caution when taking the voltage readings on the back of the power PCB - see warning
above. Use an isolated or "floating" digital volt meter, since high voltages are present. The following
table lists the test points, their descriptions and values. Refer also to Figure 3-15 to locate test points.
Power Board Test Points
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