EVCO S.p.A.
c-pro 3 nano CHIL | Application manual ver. 1.0 | Code 144CP3NCHE104
page 55 of 90
PC05 = Minimum compressor switch-off time. This is a minimum time interval that must go from the last switch-off, before the
compressor can be turned on again.
PC06 = Minimum time between two switch-ons of the same compressor. Determines the min. period that must elapse between two
start-ups of the same compressor.
PC07 = Minimum time between two switch-ons of different compressors. Determines the minimum time that must elapse between
switch-on of a compressor and that of the next compressor.
PC08 = Minimum time between two switch-offs of different compressors. Determines the minimum time that must elapse between
switch-off of a compressor and that of the next compressor.
PC09 = Maximum number of start-ups of the compressor in an hour. Determines the maximum number of start-ups in a time interval
of an hour: if this limit is reached, the regulator waits until the conditions form before turning on the compressor again.
Neutral Zone Periods
These parameters are used to determine the switch-on/switch-off timing of different compressors.
PC17 = Extra time for switch-on/switch-off request
8.7.6 Thermal switch Inputs
The programme sees to the management of a thermal safety switch input for each compressor. For this input you can set the type of
reset (manual or automatic) in the parameters, as well as activation delay.
8.8 Condenser Control
The condenser control regulates the condensation pressure modulating the airflow through an analogue output (inverter or phase cut),
or with a single-phase fan for each circuit. The condenser control is set with parameter PF01:
• PF01 = 0. Single-phase control
• PF01 = 1. Modulating control.
If parameter PF02 is set on 0, the control will be independent from the temperature control; otherwise, the fan will turn on only if the
control requests switch-on of at least one compressor.
Whether or not the fan must be turned off during the defrost cycle is a condition to be set with parameter PF03: if PF03 is set on 1, the
fans stop during defrost.
If parameter F09 is set on 1, if there is an condensation probe alarm with single-phase control, the fans will be forced.
8.8.1 Modulating Fan Control
Thanks to continuous control of the fans with an inverter (output A03, type 0-10 V) or with a phase-cutting module (pulsed output
A01), you can perform a proportional control (or proportional/integral) of the condensation.
The control of fan speed provides a minimum speed value to manage the start-ups in a way so as to keep the fan’s motors from
operating at an RPM speed that is too slow. Also, you can set an Acceleration Time PF28 upon start-up, during which the fan will reach
maximum speed.
You also have the option to maintain the fans at minimum speed, also below the setpoint value. If the pressure should drop very far
below the setpoint of a certain threshold, the fan will be forced to switch off.
Lastly, there is a high-speed value beyond which the speed remains constant. If the maximum forcing has been enabled, if the pressure
should continue to increase beyond a certain threshold, the fan speed would be forced to 100%.
The figure below shows the behaviour of continuous control in the event of summer operation (chiller). In this specific control, the
proportional band is moved completely above the setpoint.
Note: Both A01 and A03 outputs will have the same control signal. The A01 output has a type in PWM output and can be used with
the single phase cutting module EVFan. The A03 output has a type in output 0..10V and can be used with Schneider Electric ATV motor.
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