Specifications
Table Of Contents
- Cover
- Table of Contents
- Part 1 General Information
- Part 2 Specifications
- Part 3 Refrigerant Circuit
- Part 4 Function
- Part 5 Test Operation
- Part 6 Troubleshooting
- Part 7 Appendix
- 1. Piping Diagrams
- 2. Wiring Diagrams for Reference
- 3. List of Electrical and Functional Parts
- 4. Option List
- 5. Piping Installation Point
- 6. Example of connection (R-410A Type)
- 7. Thermistor Resistance / Temperature Characteristics
- 8. Pressure Sensor
- 9. Method of Checking the Inverter’s Power Transistors and Diode Modules
- Part 8 Precautions for New Refrigerant (R-410A)
- Index
- Drawings & Flow Charts
Protection Control Si34-704
106 Function
4.2 Low Pressure Protection Control
This low pressure protection control is used to protect compressors against the transient
decrease of low pressure.
★
In the case of multi-outdoor-unit system, the entire system performs this control in the
following sequence.
Low pressure not limited
Pe<0.34MPa
Low pressure standby
Low pressure limited
All STD compressors
stop.
Master unit:52 Hz + OFF + OFF
Slave unit:Stop
Pe<0.25MPa
Pe<0.15MPa Pe>0.30MPa
Pe>0.39MPa
Pe<0.07MPa
Pe: LP pressure sensor detection
value for master unit
When occurring 4 times within 30 min.,
the malfunction code “ E4 ” is output.
Hot gas SVP = OFF
Hot gas SVP = ON