Technical description
iDRY iRDP CT 20-500
17
8.9
Hot-gas bypass valve
At partial load, the valve directly returns a part of the hot gas to the suction line of the refrigerating compressor. The
evaporation temperature and the evaporation pressure remain constant.
ADJUSTMENT
The hot gas by-pass valve is adjusted during the manufacturing testing phase.
As a rule no adjustment is required; anyway if it is necessary the operation
must be carried out by an experienced refrigerating engineer.
WARNING
the use of ¼” Schrader service valves must be justified by a real malfunction
of the refrigerating system. Each time a pressure gauge is connected, a part
of refrigerant is exhausted.
Without compressed air flow through the dryer, rotate the adjusting screw
(position A on the drawing) until the following value is reached:
Hot gas setting :
R134.a pressure 31.9 psig (+ 1.45 / -0 psi) [2.2 barg (+0.1 / -0 bar)]
R407C pressure 68.2 psig (+1.45 / -0 psi) [4.7 barg (+0.1 / -0 bar)]
A
4 mm
5/32 in.
+
-
V
L
Y
0
0
0
1
8.10 Refrigerant pressure switches LPS – HPS – PV
To ensure the operational reliability and the protection of the dryer, a series of pressure switches are installed in the
gas cycle.
LPS :
Low-pressure guard on the suction side of the compressor, which is triggered when the pressure drops below
the predetermined value. The values are reset automatically as soon as the nominal conditions are re-
established.
Calibrated pressure :
R 134.a
Stop 10.2 psig (0.7 barg) - Restart 24.7 psig (1.7 barg)
R 407 C
Stop 24.7 psig (1.7 barg) - Restart 39.2 psig (2.7 barg)
HPS :
The high-pressure control unit on the discharge side of the compressor is activated when the pressure
exceeds the predetermined value. It has a manual reset button on the control itself.
Calibrated pressure :
R 134.a
Stop 290 psig (20 barg) - Manual reset P<203 psi (P<14 bar)
R 407 C
Stop 435 psig (30 barg) - Manual reset P<334 psi (P<23 bar)
PV :
Fan control pressure switch which is installed on the discharge side of the compressor. It keeps the
condensation temperature and pressure constantly in the range of the preadjusted limit values
Calibrated pressure :
R 134.a
Start 160 psig (+7.25 / -0 psi) [11 barg (+0.5 / -0 bar)]
Stop 116 psig (+0 / -7.25 psi) [8 barg (+0 / -0.5 bar)]
R 407 C
Start 261 psig (+7.25 / -0 psi) [18 barg (+0.5 / -0 bar)]
Stop 203 psig (+0 / -7.25 psi) [14 barg (+0 / -0.5 bar)]
8.11 Compressor crankcase heater (iRDP CT 200-500 3phase)
At low temperatures, the oil can more easily intermix with the refrigerant gas. When the compressor starts, oil can be
drawn into the refrigeration cycle, leading to "hydraulic shocks".
To prevent this, a resistance heater is installed in the suction side of the compressor. When the system is connected
with the electric mains and the compressor is idle, the heater will keep the oil at the correct temperature.
This heater is controlled via a temperature switch which prevents the overheating of the oil.
Note:
The heater must be connected to the mains at least a few hours prior to the start-up of the refrigerating
compressor.
Содержание iDRY iRDP CT 30
Страница 28: ...Technical data 28 iDRY iRDP CT 20 500 11 Technical data 11 1 Technical data iDRY iRDP CT 20 200 1 1 115 60...
Страница 29: ...Technical data iDRY iRDP CT 20 500 29 11 2 Technical data iDRY iRDP CT 20 500 2 1 230 60...
Страница 30: ...Technical data 30 iDRY iRDP CT 20 500 11 3 Technical data iDRY iRDP CT 200 500 3phase 4 3 460 60...
Страница 38: ...Maintenance troubleshooting spare parts and dismantling 38 iDRY iRDP CT 20 500...
Страница 39: ...Maintenance troubleshooting spare parts and dismantling iDRY iRDP CT 20 500 39...
Страница 42: ...Appendices 42 iDRY iRDP CT 20 500 13 1 2 Dryer dimensions iDRY iRDP CT 75...
Страница 43: ...Appendices iDRY iRDP CT 20 500 43 13 1 3 Dryer dimensions iDRY iRDP CT 100 150...
Страница 44: ...Appendices 44 iDRY iRDP CT 20 500 13 1 4 Dryer dimensions iDRY iRDP CT 200 250...
Страница 45: ...Appendices iDRY iRDP CT 20 500 45 13 1 5 Dryer dimensions iDRY iRDP CT 300 350...
Страница 46: ...Appendices 46 iDRY iRDP CT 20 500 13 1 6 Dryer dimensions iDRY iRDP CT 400 500...
Страница 47: ...Appendices iDRY iRDP CT 20 500 47 13 1 7 Dryer dimensions iDRY iRDP CT 200 250 3phase...
Страница 48: ...Appendices 48 iDRY iRDP CT 20 500 13 1 8 Dryer dimensions iDRY iRDP CT 300 350 3phase...
Страница 49: ...Appendices iDRY iRDP CT 20 500 49 13 1 9 Dryer dimensions iDRY iRDP CT 400 500 3phase...
Страница 51: ...Appendices iDRY iRDP CT 20 500 51 13 2 2 Exploded diagram iDRY iRDP CT 20 30...
Страница 52: ...Appendices 52 iDRY iRDP CT 20 500 13 2 3 Exploded diagram iDRY iRDP CT 50...
Страница 53: ...Appendices iDRY iRDP CT 20 500 53 13 2 4 Exploded diagram iDRY iRDP CT 75...
Страница 54: ...Appendices 54 iDRY iRDP CT 20 500 13 2 5 Exploded diagram iDRY iRDP CT 100...
Страница 55: ...Appendices iDRY iRDP CT 20 500 55 13 2 6 Exploded diagram iDRY iRDP CT 125 150...
Страница 56: ...Appendices 56 iDRY iRDP CT 20 500 13 2 7 Exploded diagram iDRY iRDP CT 200 250...
Страница 57: ...Appendices iDRY iRDP CT 20 500 57 13 2 8 Exploded diagram iDRY iRDP CT 300 350...
Страница 58: ...Appendices 58 iDRY iRDP CT 20 500 13 2 9 Exploded diagram iDRY iRDP CT 400 500...
Страница 59: ...Appendices iDRY iRDP CT 20 500 59 13 2 10 Exploded diagram iDRY iRDP CT 200 250 3phase...
Страница 60: ...Appendices 60 iDRY iRDP CT 20 500 13 2 11 Exploded diagram iDRY iRDP CT 300 350 3phase...
Страница 61: ...Appendices iDRY iRDP CT 20 500 61 13 2 12 Exploded diagram iDRY iRDP CT 400 500 3phase...
Страница 71: ...Appendices iDRY iRDP CT 20 500 71...
Страница 72: ...Independent Compressor Partners LLC Jeffersonville IN 47131 www icompressorpartners com 7425MUM289_EN_2014 09...