dixell ichill IC260L, User Manual

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1592015300 User manual iCHILL 200 L GB r1.3 09/09/2005
30.4 U
NLOADING WITH
P
RESSURE
, C
ONDENSING TEMPERATURE OR
E
VAPORATING PRESSURE
CONTROL
The function is always enabled for both the running mode in order to reduce the load and helps the unit to start: in chiller for high
temperature of the external air to avoid high pressure alarms, in heat pump for low temperature of external air to avoid the low pressure
alarms.
The compressor unloading in chiller mode is managed by the analogue input configured as condenser probe circuit 1 or 2 and
determined by CF07 (0=temperature, 1 = pressure)
The compressor unloading in heat pump mode is managed by the analogue input configured as evaporator probe circuit 1 or 2. If not
configured the heat pump unloading is managed from the condenser transducer.
30.5 R
EGULATION
UNLOADING IN CHILLER MODE
When the chiller thermoregulation request begins to start the compressors, if the condenser pressure/temperature is equal or bigger
than CO44 setpoint the unloading process, of that circuit probe, is engaged. The bottom display shows, alternated with the
measurement, the
b1Cu or b2Cu labels. The number of active compressors/step is determined by the CO49 parameter.
EXAMPLE
Unit with 2 circuits with 3 compressors each.
If Par. CO49 = 2, 2 power steps per circuit, in case of unloading there will be 4 compressor running.
With capacity compressors and with unloading active, to avoid having a not well balanced circuit after reducing the power (step valve
on) the resource (the valve) is activated for the time set in CO50 even if the unloading function is not more activated and the
thermoregulation requires 100% of power. If CO50=0 the function is disabled and if necessary the valve is turned immediately off to
have the 100% of the power.
UNLOAD DE-ACTIVATION in CHILLER MODE
If the temperature decreases under the value determined by (CO44-CO45) setpoint – differential, the unloading is disengaged, the
compressors are all available for the thermoregulation.
30.6 O
THER INFORMATION ABOUT THE
U
NLOADING IN CHILLER
To avoid having long period of unloading function activated when the temperature or the pressure value is continuously within the SET
and SET+ differential, if the temperature or the pressure is higher than CO40, the CO48 time delay forces the unloading off for timeout
even if the temperature / pressure is not lower than CO44-CO45.
UNLOADING IN HEAT PUMP MODE
The compressor unloading in heat pump mode is managed by the analogue input configured as evaporator probe circuit 1 or 2.
When the heat pump thermoregulation request begins to start the compressors, if the evaporator pressure/temperature is equal or
bigger than CO46 setpoint the unloading process, of that circuit probe, is engaged. The bottom display shows, alternated with the
measurement, the
b1Cu (crcuit2)or b2Cu (crcuit2)labels. The number of active compressors/step is determined by the CO49
parameter.
EXAMPLE
Unit with 2 circuits with 3 compressors each.
If Par. CO49 = 1, 1 power steps per circuit, in case of unloading there will be 2 compressor running, 1 per circuit.
With capacity compressors and with unloading active, to avoid having a not well balanced circuit after reducing the power (step valve
on) the resource (the valve) is activated for the time set in CO50 even if the unloading function is not more activated and the
thermoregulation requires 100% of power. If CO50=0 the function is disabled and if necessary the valve is immediately off to have the
100% of the power.
UNLOAD DE-ACTIVATION in HEAT PUMP MODE
If the evaporator temperature increases the value determined by (CO46+CO47) sedifferential, the unloading is disengaged, the
compressors are all available for the thermoregulation.
30.7 O
THER INFORMATION ABOUT THE
U
NLOADING IN
H
EAT
P
UMP
To avoid having long period of unloading function activated when the temperature or the pressure value is continuously within the SET
and SET+ differential, if the temperature or the pressure is higher than CO46, the CO48 time delay forces the unloading function off for
timeout event, even if the temperature / pressure is not lower than CO46+CO47.
31 SOLENOID VALVE FOR LIQUID INJECTION
There are two outputs relay that can be configure as solenoid valve compressor 1 and 2. The function is enabled when:
•
For compressor 1: one output relay is configured as solenoid valve compressor 1 and one analogue input is configured as
discharge temperature of compressor 1.
•
For compressor 2: one output relay is configured as solenoid valve compressor 2 and one analogue input is configured as
discharge temperature of compressor 2.
31.1
FUNCTIONNING
When the compressor is off the solenoid valve output is always OFF . When the compressor is on: if the PTC temperature of the
compressor discharge reaches CO51 setpoint the valve turns ON, while if the temperature decreases under C51-CO52 (set- differential)
the valve turns off.