User Manual

Control concept

Desigo room automation

CM110664en_07 97 | 351

In a humidity control system with various physical control variables, the initial value of the integrator should

be predefined.

Example:

If the humidity of the supply air is measured with an absolute humidity value [g/kg], while the room air

humidity is measured in terms of relative humidity [%Hu], an initial value must be defined for the I-

component, otherwise the mean value from [SpLoR] and [SpHiR] will be used as the initial value. If the

room set points are expressed in terms of relative humidity, then the initial value for the integrator will start

at a numerically high value, and decrease as a function of the preset integral action time [Tn]. The result of

this can be that even if the room needs to be dehumidified, the humidifier is enabled in the controller start-

up phase until the integrator reaches its correct value.

To prevent this, the current measured supply air humidity value is linked to the initial value of the

integrator, or a fixed parameter value is defined for the integrator.

If control accuracy is critical (e.g., no deadband or zero-energy control zone), then the current measured

value is linked to the initial value of the integrator, or a fixed parameter value is defined for the integrator.

5.5 Desigo room automation

Multiple mechanical and electrical installations (referred to as technical installations in this chapter) come

together in one room. These typically are HVAC, lighting, and blinds. Each technical installation is

automated and operated optimally from its perspective. For Desigo room automation, coordination of the

individual technical installations must be optimized while considering that the same type of installation may

exist several times in one room.

Room featuring:

1. HVAC zone (blue)

2. Lighting zones (yellow)

3. Shading/blinds zones (green)

HVAC zone

The room typically is considered 1 HVAC zone influenced via a common automation and control strategy

regardless of number and type of installed HVAC plant components (e.g., radiator, chilled ceiling, fan coil

unit).

Lighting zone