Sauter flexotron®800
ventilation
Functional description
P100012082
31
5
Functional description
5.1
Temperature control
General
The controller flexotron®800 has a choice of the following control modes:
1. Supply air control
2. Outdoor temperature compensated supply air control
3. Cascaded room temperature control
4. Cascade connected extract air temperature control
5. Outdoor temperature dependent switching between room control and supply air
control
6. Outdoor temperature dependent switching between extract air control and
supply air control
The supply air temperature controller is reverse acting, i. e. the output will increase for
decreasing temperature. The controller is a PI-controller with settable P-band and I-
time.
In the first two modes the supply air temperature will be controlled using the supply air
temperature and the user setpoint values as control inputs.
In modes three and four the supply air is controlled as part of a cascade controller
together with the room/extract temperature controller. The room/extract temperature
offset will dictate the supply air temperature setpoint.
Mode five and six vary according to the outdoor temperature: Supply air control in
winter and cascaded room control or cascaded extract air control in summer.
In applications with mixing dampers instead of heat exchanger the signal for the
damper control will be reversed compared to the signal for heat exchanger control i. e.
decreasing signal on increasing heat demand. This is done automatically on configuring
the exchanger output = dampers.
The heater can be either a hot water heater battery or an electric heater.
Outputs
The supply air controller output is split between one or more of the output blocks
"Heating Y1", "Exchanger Y2" and "Cooling Y3". Each of these output blocks can be
bound to either an analogue 0…10 V DC output or to two digital 3-position
increase/decrease outputs.
Each output block has two parameters for setting the control range:
Heating Controller Output signal (HCOut) at which the output should be 0 %
Heating Controller Output signal (HCOut) at which the output should be 100 %
These settings are used to establish the output activation order and to split the P-band
between the outputs.
Example:
0 % Cooling at HCOut = 30 %
100 % Cooling at HCOut = 0 %
0 % heat exch. at HCOut = 32 %
100 % heat exch. at HCOut = 50 %
0 % Heating at HCOut = 54 %
100 % Heating at HCOut = 100 %
