• SIGNA MR355 / SIGNA MR360
  • Service Manual
  • 5856356-3EN Revision 5.0
  • Basic Service Documentation. Copyright General Electric Company.
  • Object ID: 00000018WIA30307360GYZ
  • Topic ID: id_2030547 Version: 1.1
  • Date: Feb 7, 2021 12:17:40 AM

Troubleshooting the XFD-PS control board front panel LEDs

This is a LEDs introduction of XFD-PS (PN:5549353).

The power supply contains 3 transformers, one for each axis. The over current faults are separated into primary side and secondary side faults.

When the related LED lights on, some useful information is brought out. The detail information for each LED is listed below.

Table 1. Silkscreen LEDs on control board
LED Window
　　　FAULTIPX OCISX OCOVXUVXBUS UVISX
PSWFRIGHT FFFREQHSOTIPY OCISY OCOVYUVYBUS OVISY
ENABLELEFT FFGDHSUTIPZ OCISZ OCOVZUVZI TANK OCISZ
  1. ISX, ISY, ISZ: These indicate the secondary current in the power supply for each axis. They will light up when the SSSA for that axis pulls current from the power supply.
  2. IPX OC, IPY OC, IPZ OC: These indicate over current in the transformer primaries. This is an uncommon fault that would indicate a shorted transformer primary.
  3. ISX OC, ISY OC, ISZ OC: These indicate over current in the transformer secondaries. The main 2 causes maybe a blown IGBT in the SSSA or a shorted rectifier diode module in the power supply.
  4. OVX, OVY, OVZ: These indicate over voltages on the output of the power supply. Loose connectors to the SSSA can cause this problem.
  5. UVX, UVY, UVZ: These indicate under voltages on the output of the power supply. These can be caused by shorted semiconductors in the SSSA or Power Supply.
  6. I TANK OC: Indicated that the sum of the transformer primary currents is too large. This fault is uncommon. It would indicate heavy loads on all three axes at once.
  7. BUS OV: This indicates an overvoltage on the input bus of the power supply. The 380 VAC on the front of the power supply goes through a 3 phase rectifier to feed this bus. If you see this fault, check the tapping of the PDU and measure the 380 VAC on the terminal block in the front of the power supply.
  8. BUS UV: This is just like the fault above, only it indicates an under voltage. It can be caused by mis-tapping the PDU or line sags.
  9. PSWF: This indicates one of 3 possible faults. It could be an under voltage on the 5V or 15V on the control board or it is a wire fault (a connector inside of the power supply is not plugged), or the cooling fan speed is too low.
  10. FREQ: This is a control signal that indicates the frequency that the IGBTs are switching at.
  11. GD: This shows the switching of the gate drive power supply. If this light is ever solid red or solid green, it means there is a problem on the control board or gate driver board.
  12. HSOT: Cold plate over temperature. This might be caused by not connected cooling-water pipe or cooling-water in the chiller is not enough.
  13. HSUT: Cold plate under temperature. This might be caused by too cold ambient temperature or the temperature sensor cable is not plugged.
  14. FAULT: Lights on whenever one of the faults described above is happening or the reset pushbutton is pressed.
  15. LEFT FF, RIGHT FF: IGBT switching indicators. If the color of these LEDs is solid green or red, it means the IGBTs are not switching.
  16. ENABLE: Lights on when the power supply is enabled by the GP.