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Si30-408
Method of Troubleshooting
Troubleshooting
83
3.3
Structure and Operation of
Electronic Expansion Valve
For VRV system, EBM type linear control valve is employed to use as an electronic expansion
valve for superheated degree control or subcooled degree control.
In the valve, single-phase excitation drive type pulse motor is employed. On receiving 2000 pls
signal, goes to full open. The stroke of gear is 0.7 mm from full open to complete close. The
below figure shows the inside structure of driving section, and the gear ratio is 1 / 30.
Electronic expansion valve driving part
Pulse motor
Output shaft
Main body
mounting nut
Valve body
Motor shaft
Gear part
Bellows
Mold part