Hitachi RAS-3-HVNC - Protection and Safety Control

5. Control System
127
SMGB0079 rev.0 - 01/2013
5
5.3 Protection and safety control
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Compressor protection
The following devices and their combinations protect the compressor
High-pressure switch This switch cuts out the operation of the compressor when the discharge pressure exceeds the setting.
Oil heater
This band heater protects against the oil carry-over during the cold starting, as the band heater is
energized while the compressor is stopped.
Fan motor protection
Internal thermostat that is embedded in the fan motor winding: this internal thermostat cuts out the
operation of the fan motor when the temperature of the fan motor winding exceeds the setting. (only
for some RPI models)
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Safety and control device setting for the outdoor units
Model
RAS-(2-2.5)HVNP
RAS-3HVNC
RAS-3HVNPE RAS-(4-6)HVN(P/C)E RAS-(4-12)HN(P/C)(E)
For com-
pressor
Pressure Switches
Automatic Reset, Non-Adjustable (each one for each compressor)
-0.05 -0.05 -0.05 -0.05
High Cut-Out MPa 4.15 4.15 4.15 4.15
-0.15 -0.15 -0.15 -0.15
Cut-In MPa 3.20±0.15 3.20±0.15 3.20±0.15 3.20±0.15
For fuse
control
1~ 230V 50Hz
A 25 40
50
(RAS-4HVNCE = 40)
3N~ 400V 50Hz
A 2 X 20
CCP Timer
Setting Time
min.
Non-Adjustable
3 3 3 3
Discharge gas
Thermistor
ºC
115 (OFF) Cooling
115 (OFF) Heating
115 (OFF) Cooling
115 (OFF) Heating
127 (OFF) Cooling
120 (OFF) Heating
127 (OFF) Cooling
120 (OFF) Heating
For Condenser Fan Motor
Internal Thermostat
Automatic Reset, Non-Adjustable (each one for each motor)
Cut-Out ºC - 120 120 120
For Control Circuit
Fuse Capacity on PCB
A 3 5 5 5