EVCO EVFTFT618N7U - Manual (Page 31)

EVCO S.p.A. EVFTFT618 | Installer manual ver. 2.2 | Code 144FTFT618E224
Page 31 of 62
9.3.1 Humidification management
Generation of humidity refers to two different utilities, a humidity generator output and a humidifier output.
The humidity generator output is activated during the phases in which management of humidification is envisioned; it is
used for machines with external boiler, in order to generate the steam to be introduced successively into the cabinet
whenever requested by the regulator.
The humidifier output activates when the humidity value inside the cabinet drops below the neutral area value given by
the parameter rU9 of the humidification differential value given by the parameter rU8. The percentage activation of the
humidifier output will be proportional to the value of the humidity with respect to the humidification proportional band
defined by the parameter rU10. The humidification activation/deactivation cycle time is given by parameter ru11 and
regulated on the basis of times defined by parameter rU12.
9.3.2 Dehumidification management
Dehumidification can be managed in two different ways, via an extraction/dehumidifier fan (u3=1) or via the activation of
the cooling plant (u3=1).
In the case of management via extractor fan/dehumidifier, the output will activate when the humidity has exceeded the
dehumidification neutral area, given by parameter rU6 of the value of the differential value given by the parameter rU5
and deactivates when the humidity has returned within the dehumidification neutral area value.
The compressor will behave in the same way whenever the management of the pump-down electrovalve is enabled
(parameter u1 =1).
If pump-down electrovalve management is enabled (parameter u1=0), there will first be a dehumidification attempt via
activation of the electrovalve for a period of time equal to parameter rU7, to try and make use of the high pressure
generated during pump-down in compressor switch-off, on the expiry of which, the compressor output will be activated, if
dehumidification is still requested.
Once the humidity returns within the dehumidification neutral area value, the pump-down electrovalve will be deactivated.
After which, the compressor will deactivate via the pump-down algorithm.
10 Loads management
10.1 Management of the compressor
Compressor activation is subject to the delay time between the two switch-ons (parameter C1), the delay between switch-
off and successive activation (parameter C2), the activation delay from board power on (parameter C0) and the minimum
switch-on time (parameter C3).
The compressor can also be active during hot gas defrosting (parameter d1 = 1). In this case, for the defrosting to start,
the compressor must be active for at least the time established with parameter d15.
The compressor can also be used for dehumidification; for more details see paragraph 0.
Compressor switch-off is managed differently when management of the pump-down electrovalve management is
envisioned. For greater details see the staff 0.
10.2 Pump-down management
If output K8 is configured as pump-down electrovalve (parameter u1= 0), the controller will manage the interaction
between compressor output and electrovalve output as follows:
With timed pump-down (parameter u1 = 0 and i6 = 0 or 1):
On activation of the compressor in parallel, the pump-down electrovalve will also be activated.
Compressor deactivation will be advanced by the deactivation of the pump-down electrovalve; after time u2 the
compressor outlet will also be deactivated.