EVCO EPU2LXP1CH Installer manual - Manual (Page 61)

EVCO S.p.A. c-pro 3 micro CHIL | Application manual ver. 1.0 | Codice 144CP3CHE104
page 61 of 120
Neutral-zone timings
These parameters are used to time the request for switching ON/OFF the various compressors.
PC17 = Extra time for ON/OFF switching request
8.7.6 Thermal protection inputs
The program provides for the management of a compressor thermal safety switch input for each compressor. For this input, it is
possible to set, via parameters, the type of reset (manual or automatic), as well as the triggering delay.
8.8 Condenser control
Condenser control controls the condensing pressure by modulating the air flow via an analogue output (inverter or phase-cut), or with a
single stage fan for each circuit. Condenser control is set by parameter PF01:
• PF01 = 0: Single stage control
• PF01 = 1: Modulating control.
If parameter PF02 is set to 0, control will be independent of temperature control; otherwise, fans will be activated only if the controller
requests the switching ON of at least one compressor.
The parameter PF03 sets whether or not fans must switch OFF during defrosting cycles, if PF03 is set to 1 fans will stop during defrost.
If parameters PF09 is set to 1, fans are forced in case of condensing sensor alarm with single stage Control. If the control is Modulated
the parameter PF10 set the value to force.
8.8.1 Modulating fan control
Thanks to the continuous control of fans, a proportional (or proportional/integral) control of condensation is performed, via an inverter
(output A03, 0-10 V type), or via a phase-cut module (pulsed output A01).
Fan speed control provides for a minimum speed value, to manage start-ups in such a way as to avoid operating fan motors at an
excessively low rpm rate. In addition, it is possible to set a Speed-up time PF28 at start-up, during which the fan will reach maximum
speed.
The possibility is provided for, of maintaining the fans at minimum speed, even below the set point value. Should pressure decrease
further below the set point of a given threshold, fan switching OFF is forced.
There is, in addition, a high-speed value beyond which velocity remains constant. If maximum forcing has been enabled, should
pressure increases further, exceeding a given threshold, fan speed will be forced to 100%.
The following figure illustrates the behavior of continuous control in the case of summer operation (chiller). In this particular control,
the proportional band is completely shifted above the set point.
Note: Both outputs A01 and A03 will have the same control signal. Output A01 has a PWM output type and can be used with the single
phase cutting module EVFan. The output A03 has a 0..10V output type and can be used with Schneider Electric ATV drive..