Daikin VRV S RXQ4/5ARV1, Service Manual

Page: 359 / 377

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 Press u re (P
H
)
Lo w Press u re (P
L
)
O u tp u t V oltage V
H
, V
L
Detected Press u re
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
( V DC)
(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 press u re (MPa)
P
L
: Lo w press u re (MPa)
V
H
: O u tp u t V oltage (High Side) ( V DC)
V
L
: O u tp u t V oltage (Lo w Side) ( V DC)
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