Appendix, Vcm-x modular e-bus controller technical guide – Orion System VCM-X Modular E-BUS User Manual
Page 77
VCM-X Modular E-BUS Controller Technical Guide
APPENDIX
77
OE275-01 Suction Pressure Transducer Testing
OE275-01 Suction Pressure
Transducer Testing for R22 and R410A
Refrigerant
The Evaporator Coil Temperature is calculated by converting the Suc-
tion Pressure to Temperature. The Suction Pressure is obtained by using
the OE275-01 Suction Pressure Transducer, which is connected into the
Suction Line of the Compressor.
Use the voltage column to check the Suction Pressure Transducer while
connected to the VCM-X Expansion Module. The VCM-X and the
VCM-X Expansion Module must be powered for this test. Read voltage
with a meter set on DC volts. Place the positive lead from the meter
on the PR OUT terminal located on the VCM-X Expansion Module
terminal block. Place the negative lead from the meter on the ground
(GND) terminal located adjacent to the PR OUT terminal on the VCM-X
Expansion Module terminal block. Use a refrigerant gauge set and/or an
accurate electronic thermometer to measure the temperature or suction
line pressure near where the Suction Pressure Transducer is connected
to the suction line. Measure the Voltage at the terminals PR OUT and
GND terminals and compare it to the appropriate chart depending on
the refrigerant you are using. If the temperature/voltage or pressure/volt-
age readings do not align closely with the chart, your Suction Pressure
Transducer is probably defective and will need to be replaced.
See the OE275-01 Suction Pressure Transducer, Pressure, Temperature,
and Voltage Chart for R22 and R410A Refrigerant testing (Tables 8
and 9). The charts show a temperature range from 20°F to 80°F. For
troubleshooting purposes, the DC Voltage readings are also listed with
their corresponding temperatures and pressures.
OE275-01 Suction Pressure Transducer
Coil Pressure
– Temperature – Voltage Chart for R22 Refrigerant
Temper
at
ur
e
°F
Pr
essur
e
PSI
Signal DC V
olts
Temper
at
ur
e
°F
Pr
essur
e
PSI
Signal DC V
olts
20.00
31.13
1.0
55.32
93.39
2.0
20.00
37.36
1.1
58.86
99.62
2.1
20.46
43.58
1.2
62.13
105.84
2.2
25.71
49.80
1.3
65.27
112.07
2.3
30.84
56.03
1.4
68.42
118.29
2.4
35.41
62.26
1.5
71.39
124.52
2.5
39.98
68.49
1.6
75.20
130.75
2.6
44.00
74.71
1.7
77.00
136.97
2.7
48.00
80.94
1.8
79.80
143.20
2.8
51.78
87.16
1.9
80.00
149.42
2.9
Table 9: Coil Pressure/Voltage/Temp for OE275-01
Suction Pressure Transducers - R410A Refrigerant
Table 8: Coil Pressure/Voltage/Temp for OE275-01
Suction Pressure Transducers - R22 Refrigerant
OE275-01 Suction Pressure Transducer
Coil Pressure
– Temperature – Voltage Chart for R410A
Refrigerant
Te
mper
at
ur
e
°F
Pr
essur
e
PSI
Signal DC V
olts
Te
mper
at
ur
e
°F
Pr
essur
e
PSI
Signal DC V
olts
21.19
80.94
1.8
59.03
168.10
3.2
24.49
87.16
1.9
61.17
174.32
3.3
27.80
93.39
2.0
63.19
180.55
3.4
30.99
99.62
2.1
65.21
186.78
3.5
33.89
105.84
2.2
67.23
193.00
3.6
36.80
112.07
2.3
69.24
199.23
3.7
39.71
118.29
2.4
71.15
205.46
3.8
42.30
124.52
2.5
72.95
211.68
3.9
44.85
130.75
2.6
74.76
217.91
4.0
47.39
136.97
2.7
76.57
224.14
4.1
49.94
143.2
2.8
78.37
230.36
4.2
52.23
149.42
2.9
80.18
236.59
4.3
54.50
155.65
3.0
56.76
161.88
3.1