Hypertherm Powermax65 Service Manual Rev.1 - Manual (Page 179)

TroubleshooTing and sysTem TesTs
powermax
65/85 Service Manual 5-53
Test 10 – Pressure sensor
Symptom: The pressure sensor reading doesn’t agree with known pressures.
Note: Wear proper personal protective equipment (PPE) before testing powered equipment.
1. Remove the white cover on the plug at J5 for CSA units or J7 for CE units.
2. Turn the machine on.
3. Measure power to the sensor between Pin 2 and Pin 3.
If not 5.0 (±5%) perform the Flyback Circuit test above.
4. Display the service screen (refer to page 5-21 Displaying the service screen). Enable the gas test by moving the
cursor to the “G” field and turning the adjustment knob to display “1” in the field. To turn off the gas test, turn the
adjustment knob to display “0” in the field.
Note the flowing gas pressure in the “P” field to the right of the slash.
5. Measure VDC between Pin 2 (-) and Pin 1 (+)
The value should be 0.0463 times the pressure, for example (68 PSI * .0463 VDC/PSI = 3.148 VDC).
If the voltage measurement is within ±10% of the correct value and you have a pressure warning or fault:
a. Test with a known working DSP board.
b. If the measured voltage is correct, replace the DSP board.
c. If the measured voltage is not correct, replace the pressure sensor.