User Manual

10
demand. But, no cooling and reheating is required to achieve the relative room
humidity in this range. This lowers costs thanks to lower cooling energy
requirements.
– For "humidification only", the relative humidity actual value is projected to the
relative humidity line. This results in greater humidification demand. But, no
cooling is required in this range. This in turn lowers costs, as humidification
normally costs less than cooling.
Figure 3-4
Possible state changes in the h,x diagram for the comfort area.
See Section 11-2 for additional information on the h,x diagram.
Cascade controller
Advantages:
– Better dynamic behavior
The dynamic controller (Figure 3-3) comprises a cascade controller for temperature
and humidity control. Temperature and relative humidity represent measured
variables, temperature and absolute humidity, however, represent reference
variables. The absolute humidity is calculated from temperature and relative
humidity. This conversion decouples the two reference variables, resulting in
improved dynamic behavior.
The cascade contains two important components:
– Room controller
– Supply air controller