ACME Koolmaster PP20-VS2, User Manual

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KOOLMASTER PP20-VS2 rev.00
KOOLMASTER PP20-VS2
6.3.4. Curtain Compensation
The controller can slightly adjust opening of
the curtains as a function of outside tempera-
ture: as the outside temperature increases,
the controller increases the opening time of
the curtains. As a result, curtains open faster
when the outside temperature gets warm.
Likewise, when the outside temperature
gets cold the controller increases the closing
time of the curtains. This compensation is
optional. To use it, enable the curtain com-
pensation in the Installation Setup (section
4.5). Then, set the outside temperature set
point (sec. 5.1).
When temperature rises:
When the curtain opens, the controller in-
creases the curtain’s
“On Time”
by 4% for
every 1°F (0.6°C) in the compensation inter-
val (i.e. an interval of 3°F means a 12% in-
crease). The curtain’s
“Off Time”
is decreased
by the same amount.
Compensation interval
Outside T°
Set Point
Current
Outside T
When temperature falls:
When the curtain closes, the controller in-
creases the curtain’s
“On Time”
by 4% for ev-
ery 1°F (0.6°C) in the compensation interval
(i.e. an interval of 3°F means a 12% increase).
The curtain’s
“Off Time”
is decreased by the
same amount.
Compensation interval
Outside T°
Set Point
Current
Outside T
6.3.5. Stopping Fans in Natural Vent.
Whisker switches are used to stop some on/
off and variable-speed fans when the control-
ler is in natural ventilation. These switches
actually tell when the curtains are sufficiently
opened.
When temperature rises (point A on the
graph):
The controller gradually opens the
curtain as temperature rises in the room. It
can also disable a chosen selection of fans
when the curtain is sufficiently opened (when
the curtain has reached its whisker switch).
When temperature falls (point B on the graph):
At point B, the curtain is already opened and
the fans are stopped. The controller gradually
closes the curtain as temperature falls. The
controller restarts the fans when the curtain
closes and releases its whisker switch.
Fan Shutoff
in Natural Vent.
The curtain
closes
in timer mode
The curtain
opens
in timer mode
The curtain
reaches the
Whisker switch:
the fans turn off.
The fans restart
when the whisker
switch is released.
Room T°
Room T°
Curtain
status
Fan output
ON
ON
OFF
OFF
Security Function : If the temperature drops
suddenly or if the whisker switch is defective,
the controller automatically restarts the fans
when the temperature falls 5°F (3°C) below
the lowest curtain’s closing temperature.
When this situation occurs, a defective whis-
ker switch alarm is posted to the alarm log
.
Select: 1.
Current Conditions (Main Menu)
Start/Stop*
Natural **
Hi T° Restart ***
* A password may be required to access this menu.
** Accessible if at least 1 natural ventilation curtain
is enabled in the Installation Setup (section 4.5).
*** Accessible if at least 1 natural ventilation curtain
uses a whisker switch (section 4.5).
Natural Ventilation
Use to navigate
Hi T° Restart 89.0 °F
Set the following parameters: 2.
Refer to section 4.8 to select the fans
that need to be stopped when the whisker
switch is engaged.
Hi T° Restart — If the room temperature is
higher or equal to the
“Hi T° Restart”
value and
we are in natural ventilation, the inlets will
open and the shutoff fans will restart after
the inlets are in position