Troubleshooting for low fan speeds – CAB FAN 1
Diagnostic codes 747 and 750
Diagnostic codes 747 and 750 occur when the CAB FAN 1 fan is under performing.
Symptoms
| Code | Symptoms | XPR® models | XPR action | Code cancels with... |
|---|---|---|---|---|
| 747 | The fan speed for CAB FAN 1 is less than the minimum acceptable Revolutions Per Minute (RPM) value. | XPR460™ | None |
|
| 750 | The fan speed for CAB FAN 1 is less than the minimum acceptable RPM value. | XPR170™, XPR300™ |
Corrective action
- Use the Fan diagnostic codes diagram to identify the location of CAB FAN 1 in the plasma power supply.
-
Make sure that the following fan connections are good, and tighten
loose connections if found:
- The fan connector
- The wiring to J7 on the fan power distribution Printed Circuit Board (PCB)
- The wiring to J7 on the control PCB
- Tighten loose connections if found.
- Examine the 48 VDC power source output.
- If the power output is not correct, replace the 48 VDC power source.
- If you do not find any loose connections and the 48 VDC power source is good, replace the fan.