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16.AUXILIARY FUNCTIONS
16.2 Liquid injection thermostats:
The liquid injection thermostats can be used for compressor cooling. It is possible to associate one thermostat for each compressor. To enable a
thermostat, it is necessary to configure a setpoint for the compressor working temperature, a hysteresis, a temperature sensor, and a digital output. The
output is activated when the compressor temperature is higher than the setpoint plus the hysteresis and will be switched off when the temperature is
lower than the setpoint. The thermostat control remains disabled while the compressor is off.
16.3 Adiabatic cooling:
The adiabatic cooling logic allows to reduce the temperature of the outside air in contact with the condenser and thereby reduce the operating pressure
of the discharge. The adiabatic cooling control drives a water pump or valve that feeds the water curtain through which the outside air passes before it
reaches the condenser.
The output is activated by temperature control, using one or two sensors, or exclusively by time, operating by means of a cyclical timer (time on and time
off). The control is permanently enabled unless otherwise determined by the time parameters Start time (
1.7.3.1.11
) and End time
(
1.7.3.1.12
) or associated with a digital input.
16.3.1 Control by temperature:
In the mode of control by temperature, a sensor must be installed to measure the outside air temperature (dry bulb sensor) and optionally another
sensor to measure the temperature of the air after passing through the water curtain (wet bulb sensor).
The control output is activated whenever the differential between the readings of the two sensors is smaller than the Activation differential
(
1.7.3.x.4
) and is deactivated when the differential is greater than the Deactivation differential (
1.7.3.x.5
). Two sensors are required in this
case, one for dry bulb temperature and one for wet bulb temperature.
Setpoint
Se
hysteresis
ON
OFF
ON
OFF
Temperature
Compressor
Output
Activation
differential
Deactivation
differential
ON
OFF
Temperature
Output