Sauter flexotron®800
ventilation
Functional description
P100012082
45
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.
Digital humidity signal
A digital output signal, "Dehumidification/Humidification", can be used for on/off control
of humidifiers/dehumidifiers. The output signal has an activation value and a
deactivation value which are connected to the humidity controller output. The signal is
activated when the humidity controller output rises above the set activation value and is
deactivated when the humidity controller output drops below the set deactivation value.
Inputs and outputs
AI
Room humidity sensor
AI
Duct humidity sensor
AO
Humidity control output 0…10 V DC
DO
Dehumidification/Humidification
5.4
Fan control
General
Fans can be 1-speed, 2-speed or variable speed via a frequency converter.
1-speed fans are controlled using the digital outputs "Start SAF-Normal" and "Start
EAF-Normal".
2-speed fans are controlled using the digital outputs "Start SAF-Normal" and "Start
EAF-Normal" as well as "Start SAF-reduced" and "Start EAF-reduced" giving normal
and reduced speed respectively.
Variable speed control uses an analogue output per fan for controlling a frequency
converter. There are two setpoints for each fan, "Normal" and "Reduced". Pressure or
air flow control can be used.
Variable speed fans can also be configured to be run with fixed output values.
Compensation curve
When running pressure control, it is also possible to temperature compensate the
pressure.
Crosswise interlock
Crosswise interlock of fans can be configured, which e.g. means that if one fan stops,
the other fan will also stop.
Timer outputs, interlock at low outdoor temperatures
The fans are normally controlled by the timer channels for normal and reduced speed.
At very low outdoor temperatures, "2-speed fans" or "pressure controlled fans" can be
forced to "reduced speed". The limit temperature is settable and the function has a
differential of 2K.
Normal, reduced speed
Units with 2-speed or pressure control fans are always started at "reduced speed". After
a settable time, the controller switches to "Normal speed" if normal speed is valid at
start-up. When 2-speed fans are switched from "Reduced speed" to "Normal speed",
"Reduced speed" is first disengaged. About 2 sec later, "Normal speed" is activated.
