52
OCH751
<Output pulse signal and the valve operation>
(2) Linear expansion valve operation
A
B
C
Open
Extra tightening (about 32 pulse)
Pulse number
500 pulse
Opening a valve
all the way
Close
Valve position (capacity)
Close
Open
The output pulse shifts in the following order.
Opening a valve: 8 → 7 → 6 → 5 → 4 → 3 → 2 → 1 → 8
Closing a valve: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 1
· When linear expansion valve operation stops, all output phases
become OFF.
· When the power is turned on, 700 pulse closing valve signal will
be sent till it goes to
A
point in order to define the valve position.
(The pulse signal is being sent for about 20 seconds.)
· When the valve moves smoothly, there is no sound or vibration
occurring from the linear expansion valve : however, when the
pulse number moves from
B
to
A
or when the valve is locked,
more sound can be heard.
No sound is heard when the pulse number moves from
B
to
A
in
case coil is burnt out or motor is locked by open-phase.
· Sound can be detected by placing the ear against the screw driv
-
er handle while putting the screw driver to the linear expansion
valve.
LEV
M
1
6
ø4
ø4
ø3
ø2
ø1
1
RD
BU
OG
YE
WH
2
3
4
5
Connector LEV-A
LEV-B
12 VDC
Outdoor controller circuit board
Drive circuit
ø3
ø2
ø1
3
2
5
4
Linear expansion valve
(1) Operation summary of the linear expansion valve
• Linear expansion valve opens/closes through stepping motor after receiving the pulse signal from the outdoor controller circuit
board.
• Valve position can be changed in proportion to the number of pulse signal.
<Connection between the outdoor controller circuit board and the linear expansion valve>
1
ON
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
ON
OFF
ø1
Output
(Phase)
Output
ø2
ø3
ø4
2
3
4
5
6
7
8
OFF
OFF
ON
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
ON
ON
OFF
OFF
ON
