Corrigo ventilation 3.4 manu

42 Chapter 5 Functional description Manual Corrigo Ventilation, revision R
The extra controller can also be used for humidity control. The cooling battery will be used for
dehumidification if the room/extract air humidity is too high. The function uses the sensor “Extra
unit temp” and is placed immediately after the cooling battery. The function also requires use of a
room humidity or extract air humidity sensor.
Example: If the room humidity exceeds the setpoint for the function, the cooling battery will be
controlled by the external controller. The heater is controlled normally. When the room humidity
falls below the setpoint once more, the cooling control will return to normal control. A hysteresis of
1 % is added to the function.
The humidity control functions can be used for the functions ”Cascaded room temperature control”,
”Cascade connected extract air temperature control”, ”Outdoor compensated room temperature
control” as well as ”Outdoor compensated extract air control”.
An alarm will be triggered if ”Extra controller” is in manual position or if a
sensor error occurs.5.3 Humidity control
General
Humidity control can be configured as Humidification, Dehumidification or both Humidification
and Dehumidification.
Two humidity sensors can be connected, a room sensor for control and an optional duct sensor for
maximum limiting. The limit sensor can be omitted.
The humidity control is handled by a PI-controller.
The humidity sensors must give 0…10 V DC for 0…100 % RH.
Humidification
An analogue output is used to control a humidifier. The output will increase on decreasing humidity.
A digital output can also be used to start a humidifier.
Maximum limitation function using duct humidity sensor:
If the maximum limitation is 80 % RH and the hysteresis is 20 % RH, the controller output signal
will begin decreasing at 60 % RH. When halfway to 80 % RH (i.e. when at 70 % RH), half the
output signal will be damped. If the humidity in the duct still reaches 80 % RH, the entire output
signal will be damped.
Dehumidification
An analogue output is used to control a dehumidifier. The output will increase on increasing
humidity. A digital output can also be used to start a dehumidifier.
Humidification/dehumidification
An analogue output is used to control a humidifier. The output will increase on decreasing humidity.
The cooling output Y3 will be activated for dehumidification through condensation. The output will
increase on increasing humidity. This signal overrides the cooling signal from the temperature
controller so the output can be activated for dehumidification even if the temperature controller
demand is zero.
For good temperature control when using cooling for dehumidification it is important that the cooler
is placed first in the air stream so that the exchanger and heater can be used to reheat the air after
dehumidification.