20
EXPERT WW rev.12
EXPERT WW
6.2. Fan Stages
6.2.1. Principle of Operation
6.2.1.1. Operation of Fan Stages
The controller has 12 fan stages which op-
erate in a sequence to increase the level of
ventilation as the room temperature increases.
Each stage can activate on/off outputs and a
combination of timer relays for cooling pur-
poses. A fan stage is activated when the room
temperature reaches its start temperature
and is disabled when the room temperature
decreases to its stop temperature.
Operating Diagram
of Fan Stages
Room
T°
Set Point
Stage x Stop T°
Stg x
Stg y
Stage y Stop T°
Stage x Start T°
Stage y Start T°
Ventilation
Level
Start temperatures of fan stages are defined
with respect to the set point and with respect
to each other. This means that when one of
these values is adjusted, all the consecutive
values are adjusted by the same amount. For
example, if the set point is increased by 1°F,
the start temperature of all fan stages will be
increased by the same amount.
Timer-based relays in fan stages
Fan stages can activate relays that operate
following a timer (On and Off Times). This is
useful to activate misting units in timer mode
while a specific fan stage is active. Refer to
section 4.8 to enable timer-based relays.
6.2.2. Stage 1 Ramping
The controller can gradually increase (or de-
crease) the running time of the fans to smooth
out the transition from the minimum ventila-
tion cycle to full operation of stage 1 fans.
Room
Temp.
Run
Time
OnTime
=
Cycle
Time
On
Time
Min. Vent.
Stage 1 Diff.
Stage 1 Ramping
At room temperatures at or below the set
point, the controller operates the fans of
stage 1 according to the minimum ventila-
tion cycle.
If the room temperature rises above the set
point, a new
“On Time”
is calculated periodi-
cally as the temperature increases to allow
a smooth progression (from point A to point
B) up to full operation of the fans when the
set point + differential is reached (when the
“Off Time”
becomes less than 15 seconds, it
is fixed at 15 seconds until the temperature
has reached the set point + differential. At
that point, the fans of stage 1 operate con-
tinuously).
If the room temperature decreases 0.3°F
below the set point + differential, the
“On
Time”
value of the minimum ventilation cycle
decreases gradually from a value equal to
the total
“Cycle Time”
(point C) towards the
regular
“On Time”
.
Ramping Settings:
To use the ramping func-
tion, enable the
“Ramping on stage 1”
function in
the Installation Setup (section 4.5) and adjust
the differential of stage 1 in section 6.2.3.
6.2.3. Fan Stage Settings
1.
Select:
Main menu
Start/Stop*
Fan Stages
* A password may be required to access this menu.
Fan Stage Start / Stop
Use to navigate
Stage 1 Start
70.0
°F
Stop
69.0
°F
Differential 2.0 °F
Stage 2 Start
72.0
°F
Stop
71.0
°F
Stage 3 Start
74.0
°F
Stop
73.0
°F
On Time
0:15
m:s
Off Time
5:15
m:s
Stage 4 Start
76.0
°F
Stop
75.0
°F
Stage 5 Start
78.0
°F
Stop
77.0
°F
2. Set the following parameters:
(Refer to the previous section to get further informa-
tion on these parameters)
Start & Stop temperatures —
Set the start
and stop temperatures of each fan stage.
The minimum difference between two
consecutive start temperatures is of
0.5 °F (0.3 °C).
The start temperature of a fan stage
must be greater value than its stop
temperature.
Differential —
The differential is the tem-
perature difference between the moment the
Stage 1 start running in timer mode (stage 1
ramping) and the moment they run continu-
ously. Refer to the diagram in section 6.2.2.
The differential can be adjusted between
1.0°F and 10.0°F (0.6°C and 5.6°C). *
This
parameter is accessible if the ramping option is
enabled in the Installation Setup (section 4.5).
Timer —
If timer-based relays are assigned to
some fan stages (sec. 4.8), set the
“On Time”
and the
“Off Time”
of each timer-based relay.
These
“On & Off Times”
can be adjusted from
0 to 15 minutes in increments of 15 seconds.
