EVCO c-pro mega RACK - Manual (Page 86)

C-PRO MEGA RACK & C-PRO GIGA RACK APPLICATION MANUAL
Page 86
6.5 Condensation regulation
Condensation management envisages control of the supply pressure using the fans: depending on
the type of control (side band or neutral zone) and the use, or otherwise, of inverters for fine
adjustment, four types of regulation are envisaged.
6.5.1 Side band regulation
Side band control exploits the characteristics of PI (proportional and integral) or P (proportional)
regulators to establish when to insert or disengage the fans used, so as to regularise, within the
differential band, the switching on and off of the various devices. The purpose of PI regulation is to
have no error in full operation.
The parameters defining this regulation are as follows:
⋅
Proportional band (PB)
⋅
Side band supply SetPoint (SP)
⋅
Integral time (IT)
The above figure shows the behaviour of band regulation (SP, SP + PB). Depending on the supply
pressure value, regulation adds or removes the number of steps required by the fans. Under such
regulation, the band is displaced above the setPoint.
It is possible to select whether control will refer to PI or just P regulation, by either setting the
parameter for integral action, namely the integration time (Ti), or otherwise. In the specific case
where this parameter is set to the value zero, regulation is proportional only, otherwise, it is also
integral. Ti corresponds to the time necessary for integral action, assuming constant error, to
equalise the proportional action: the speed of this action is proportional to the integration time
value. The default parameter is greater than zero, hence, by default, regulation exploits the
proportional-integral characteristic.
Like the case with compressors, by means of the parameter PF78 Side band increment overlap,
with side band regulation of fans, it is also possible to improve the behaviour of the regulation band.
6.5.2 Neutral zone regulation
This type of regulation envisages the definition of a neutral zone, within which no activation or
deactivation decision will be taken, i.e. startup operations will not be requested for any of the
devices.
The parameters defining this regulation are as follows:
⋅
Neutral zone (NZ)
SP SP + BP
Fans
Max Fans
Supply pressure