Daikin VRV S RXQ4/5ARV1 - Pressure Sensor Check

SiAF332111E Check
Part 6 Service Diagnosis 353
6.12 Pressure Sensor Check
CHECK 12 Pressure Sensor and Voltage Characteristics
Voltage Measurement Point of the High Pressure Sensor
Voltage Measurement Point of the Low Pressure Sensor
*1. RXQ4/5AR
*2. RXMQ8-12AR
High Pressure (P H )
Low Pressure (P
L )
Output Voltage V H , V L
Detected Pressure
40.8
35.7
30.6
25.5
20.4
15.3
10.2
5.1
–5.1
0
45.9
51.0 5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
–0.5 0 0.5 1 1.5 2 2.5 3 3.5 4
(VDC)
(kg/cm
2
)(MPa)
P
H , P L
P H (MPa) = × V H – × 0.5
P
L (MPa) = × V L – × 0.5
P
H : High pressure (MPa)
P
L : Low pressure (MPa)
V
H : Output Voltage (High Side) (VDC)
V
L : Output Voltage (Low Side) (VDC)
4.15
3.0
4.15
3.0
1.7
3.0
1.7
3.0
+5 V
(4)
(3)
(2)
(1)
Red
Black
White
X17A *1
X32A (Red) *2
High
pressure
sensor
Microcomputer
A/D input
Make measurement of DC
voltage between these wires.
+5 V
(4)
(3)
(2)
(1)
Microcomputer
A/D input
Make measurement of DC voltage between these wires.
X18A *1
X31A (Blue) *2
Red
Black
White
Low
pressure
sensor