SiMT041311E
Control Specification
Function and Control
54
2.11 Electronic Expansion Valve Control
Outline
The following items are included in the electronic expansion valve control.
Electronic expansion valve is fully closed
1. Electronic expansion valve is fully closed when turning on the power.
2. Pressure equalising control
Open Control
1. Electronic expansion valve control when starting operation
2. Electronic expansion valve control when the frequency changes
3. Electronic expansion valve control for defrosting
4. Electronic expansion valve control when the discharge pipe temperature is abnormally high
5. Electronic expansion valve control when the discharge pipe thermistor is disconnected
Feedback Control
Target discharge pipe temperature control
Detail
The followings are the examples of electronic expansion valve control which function in each
operation mode.
Operation mode
Main control
Secondary control
Con
trol
w
hen
the
frequ
ency chang
es
H
ig
h d
isch
ar
ge
p
ipe
te
mp
er
at
ur
e con
tr
o
l
Power ON
Power initialising control
–
–
Cooling operation
Starting control
–
z
Target discharge pipe
temperature control
z
z
Stop
Pressure equalising control
–
–
Heating operation
Starting control
–
z
Target discharge pipe
temperature control
z
z
Stop
Pressure equalising control
–
–
Operation with
discharge pipe
thermistor
disconnected
Starting control
–
z
Target discharge pipe
temperature control
–
–
Stop
Pressure equalising control
–
–
z
: Available
– : Not available