Johnson Controls SGC2313 User Manual

RWF II ROTARY SCREW COMPRESSOR UNITS
MAINTENANCE
070.610-IOM (JUN 11)
Page 35
PRESSURE TRANSDUCERS - TESTING
1. Shut down the compressor and allow pressures to equalize.
2. Isolate suction transducer PE4 from the unit and depres
surize. Ensure that the transducer has proper voltage for
excitation. Measure across the red and black wires (power
and DC common) of the transducer. Voltage should be 11.8
to 15 VDC. NOTE: Recover or transfer all refrigerant vapor,
in accordance with local ordinances, before opening to
atmosphere.
3. Measure the voltage of PE4 on connector P6A (terminals
WHT and BLK) on the Analog Board with a digital voltmeter.
4. The voltage reading should be 1.48 VDC to 1.72 VDC at
standard atmospheric pressure (14.7 PSIA or 0 PSIG). When
checking transducers at higher elevations, an allowance in
the readings must be made by subtracting approximately 0.02
VDC per 1000 feet of elevation above sea level. Therefore,
if PE4 is measured at 5000 feet elevation under relatively
normal weather conditions, the output voltage should differ
by 0.10 VDC to read between 1.38 VDC and 1.62 VDC.
5. Isolate the oil pressure transducer PE1 from the package
and open it to atmosphere.
6. Measure the voltage of PE1 on connector P5A (terminals
WHT and BLK) on the Analog Board.
7. The voltage reading should be between 1.1 VDC and 1.29
VDC at standard atmospheric pressure. PE1, PE2, and PE3
all have a span of 500 PSI as compared to PE4 with a span
of 200 PSI. Therefore, atmospheric pressure changes have a
lesser effect which is 0.0067 VDC per 1000 feet of elevation
and 0.00067 VDC per 0.1 inch Hg barometric deviation.
8. Isolate transducer PE2 from the package and depres
surize. NOTE: Recover or transfer all refrigerant vapor,
in accordance with local ordinances, before opening to
atmosphere.
9. Measure the voltage of PE2 on connector P5B (terminals
WHT and BLK) on the Analog Board.
10. The voltage reading should be between 1.1 VDC and 1.29
VDC at standard atmospheric pressure (see Step 12).
11. Since the discharge pressure, PE3, cannot be closed off
from its sensing point (code require ments), close all trans
ducers from atmosphere and open them to their sensing
points so all transducers can equalize to separator pressure.
12. Measure the voltage of PE3 on connector P5B (terminals
WHT and BLK) on the Analog Board.
13. Measure the voltage of PE1 on connector P5A (terminals
WHT and BLK) on the Analog Board.
14. These two voltages should be within .04 VDC of one
another.
15. Test is complete.
PRESSURE TRANSDUCERS - REPLACEMENT
1. Shut off control power.
2. Close the applicable transducer isolation valve. NOTE: To
change the discharge pressure transducer (PE-3), it will be
necessary to depressurize the entire compressor package.
Follow "General Instructions For Replacing Compressor
Unit Components" before going to step 3.
3. Refer to the WIRING HARNESS section, External Transduc
ers for Board #1, to identify the wiring harness connectors.
4. Loosen screw and disconnect wiring harness connector
from transducer.
5. Unscrew the transducer using a wrench on the metal hex
at the base of the transducer. DO NOT ATTEMPT TO LOOSEN
OR TIGHTEN TRANSDUCERS BY THEIR TOP CASING.
6. Install new transducer.
7. Reconnect the wiring harness to the transducer.
8. Reopen the transducer isolation valve.
9. Turn on control power.
NOTE: The Pressure Transducer is factory set. If calibra-
tion is required, refer to Amalog Calibration Instruction
in publication 090-020 M.
PRESSURE TRANSDUCER CONVERSION DATA
200 psi 500 psi
Sensor Range - PSIG* Range - PSIG*
Voltage low high low high
1.0 29.92" 9.57" 29.92" 4.1
1.1 29.92" 0.3 29.92" 16.6
1.2 29.92" 5.3 17.10" 29.1
1.3 19.74" 10.3 4.1 41.6
1.4 9.57" 15.3 16.6 54.1
1.5 0.3 20.3 29.1 66.6
1.6 5.3 25.3 41.6 79.1
1.7 10.3 30.3 54.1 91.6
1.8 15.3 35.3 66.6 104.1
1.9 20.3 40.3 79.1 116.6
2.0 25.3 45.3 91.6 129.1
2.1 30.3 50.3 104.1 141.6
2.2 35.3 55.3 116.6 154.1
2.3 40.3 60.3 129.1 166.6
2.4 45.3 65.3 141.6 179.1
2.5 50.3 70.3 154.1 191.6
2.6 55.3 75.3 166.6 204.1
2.7 60.3 80.3 179.1 216.6
2.8 65.3 85.3 191.6 229.1
2.9 70.3 90.3 204.1 241.6
3.0 75.3 95.3 216.6 254.1
3.1 80.3 100.3 229.1 266.6
3.2 85.3 105.3 241.6 279.1
3.3 90.3 110.3 254.1 291.6
3.4 95.3 115.3 266.6 304.1
3.5 100.3 120.3 279.1 316.6
3.6 105.3 125.3 291.6 329.1
3.7 110.3 130.3 304.1 341.6
3.8 115.3 135.3 316.6 354.1
3.9 120.3 140.3 329.1 366.6
4.0 125.3 145.3 341.6 379.1
4.1 130.3 150.3 354.1 391.6
4.2 135.3 155.3 366.6 404.1
4.3 140.3 160.3 379.1 416.6
4.4 145.3 165.3 391.6 429.1
4.5 150.3 170.3 404.1 441.6
4.6 155.3 175.3 416.6 454.1
4.7 160.3 180.3 429.1 466.6
4.8 165.3 185.3 441.6 479.1
4.9 170.3 190.3 454.1 491.6
5.0 175.3 195.3 466.6 504.1
At 0 psig 1.094 V 1.494 V 0.968 V 1.268 V
* Below 0 PSIG measured in inches of mercury.

Johnson Controls SGC2313 Specifications

General

Brand	Johnson Controls
Model	SGC2313
Category	Air Compressor
Language	English