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EXPERT LA rev.00
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6.3
Natural Ventilation Curtains
The controller can control 2 natural ventilation cur-
tains. To operate these curtains, the controller re-
fers to the average temperature reading of the
probes that are assigned to each curtain (see sec.
4.7.3).
6.3.1
Principle of Operation
The controller enters in natural ventilation when the
average temperature of the probes that are associ-
ated to a curtai
n
reaches the
Initial Opening Tem-
perature
of the curtain. At that moment, the cur-
tain opens during its
Initial Opening Time
.
When the natural ventilation mode is on, the natural
ventilation curtain moves in timer mode: it opens
according to its opening cycle
(Open Time & Off
Time)
when the average temperature rises above
its opening temperature; likewise, it closes accord-
ing to its closing cycle
(Close Time & Off Time)
when
the temperature falls below its closing temperature.
ON
OFF
ON
OFF
Set Point
Set Point
Natural
Ventilation
Status
The curtain
closes in
timer mode
The curtain
opens in
timer mode
Stop
natural
Average T°
of the curtain’s
probes
Stage
Activation
Initial
Opening
temperature
Close at
Open at
First
tunnel stage
starts
Curtain
Status
5°F
Natural ventilation is disabled when the average
temperature decreases of 5°F (2.8°C) below the
curtain's closing temperature or when tunnel ven-
tilation starts (see graph below).
Transition from tunnel to natural ventilation
When the temperature decreases below the start
temperature of the first tunnel stage, the control-
ler opens the curtain continuously during the
Con-
tinuous Opening Delay.
When this delay has
elapsed, it starts controlling the curtain using natu-
ral ventilation settings.
Transition from natural to tunnel ventilation
When the natural ventilation curtain is opened and
the room temperature reaches the start tempera-
ture of the first tunnel stage, the controller waits
for the
Tunnel Close Delay
then fully closes the
natural ventilation curtain.
Relation between Fan Stages &
Natural Ventilation Curtains
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6.4.2
Temperature-Based Tunnel Doors
Beginning of tunnel ventilation
The activation of tunnel ventilation is linked with
the activation of a user-defined fan stage: when the
start temperature of that fan stage is reached, the
controller opens tunnel doors during the opening time
associated with that stage. The controller then acti-
vates tunnel fans when half of the opening time has
elapsed. The activation of every consecutive fan
stages causes the tunnel door to open further.
Minimum age
A minimum age can be specified to avoid entering
in tunnel ventilation when the animals are too
young. This feature is optional and can only be used
if age-based functions are enabled in the Installa-
tion Setup (section 4.5).
Minimum outside temperature
A minimum outside temperature can be specified
to avoid entering in tunnel ventilation when it is
too cold outside. This feature is optional and can
only be used if an outside temperature probe is
enabled (sec. 4.7.1).
Opening of Tunnel Doors
as a Function of Temperature
30 sec.
ROOM T°
Closed
Tunnel Door
Opening (time)
Startup of stage #x:
the tunnel door
opens according to
the opening time
associated to
fan stage #x
60 sec.
Startup of stage #x + 1:
the tunnel door
opens according to
the opening time
associated to
fan stage #x + 1.
S
ta
g
e
#
x
o
p
e
n
in
g
t
im
e
S
ta
g
e
#
x
+
1
o
p
e
n
in
g
t
im
e
Opening times
The user must associate an opening of the tunnel
door to each tunnel fan stage. When a tunnel fan
stage starts, tunnel doors open according to the
opening time associated to that stage. Opening
times are set separately for each tunnel door.
Closing vent doors (inlets) in tunnel ventilation
If vent doors (inlets) remain opened in natural ven-
tilation, you must define the tunnel stage at which
they must close.
Reference temperature in tunnel ventilation
The selection of probes that is used to measure
the room temperature can be changed in tunnel
ventilation to compensate for changes in airflow
patterns that can distort the room temperature cal-
culation. The user must select at what fan stage
the second probe set starts being used.
