Appendix, Sa controller technical guide – Orion System SA Controller User Manual
Page 61
SA Controller Technical Guide
Appendix
61
OE275-01 Suction Pressure Transducer Testing
OE275-01 Suction Pressure
Transducer Testing for 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 SA Expansion Module. The SA Controller and the
SA 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 SA 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 SA 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/voltage 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 R410A Refrigerant testing (Table 7). The chart
show a temperature range from 20°F to 80°F. For troubleshooting pur-
poses, the DC Voltage readings are also listed with their corresponding
temperatures and pressures.
Table 7: Coil Pressure/Voltage/Temp for OE275-01
Suction Pressure Transducers - R410A Refrigerant
OE275-01 Suction Pressure Transducer Coil Pressure
– Temperature – Voltage Chart for R410A Refrigerant
T
emperature
°F
Pressure
PSI
Signal
DC V
olts
T
emperature
°F
Pressure
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