Service Manual
Table Of Contents
- Cover
- Table of contents
- Part 1 List of Functions
- Part 2 Specifications
- Part 3 Printed Circuit Board Connector Wiring Diagram
- Part 4 Refrigerant Circuit
- Part 5 Functions and Control
- Part 6 Test Operation and Field Settings
- Part 7 Remote Controller
- Part 8 Troubleshooting
- 1. Troubleshooting with LED
- 2. Service Diagnosis
- 3. Error Codes and Description
- 4. Troubleshooting for CTXG, CTXS, FTXS, CDXS, FDXS, FVXS Series
- 5. Troubleshooting for FFQ Series
- 6. Troubleshooting for Branch Provider (BP) Unit
- 7. Troubleshooting for Outdoor Unit
- 8. Thermistor Resistance/Temperature Characteristics
- 9. Pressure Sensor
- 10. Method of Replacing Inverter’s Power Transistors Modules
- Part 9 Appendix
SiUS181631EA Troubleshooting for Branch Provider (BP) Unit
Troubleshooting 225
6.6 Check for Branch Provider (BP) Unit
6.6.1 Power Supply Waveforms Check
Check No.11 Measure the power supply waveform between the pins L1 and L2 on the terminal board, and check
the waveform disturbance.
Check if the power supply waveform is a sine wave (Fig.1).
Check if there is waveform disturbance near the zero-cross (sections circled in Fig.2)
Fig.1 Fig.2