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KOOLMASTER PP20-VS2 rev.00
KOOLMASTER PP20-VS2
6.2.1.3. Outside Temperature
Compensation
Stage 1 and 2 bandwidths can be adjusted
automatically as a function of outdoor
temperature compensation. As the outside
temperature decreases, stages 1 and 2 band-
widths increase gradually to compensate for
the change. The user specifies the bandwidth
used in summer as well as the bandwidth used
in winter for both variable outputs of stages
1 and 2. The bandwidths can be adjusted
from 1 to 10°F (0.6 to 5.6°C). The winter’s
bandwidth must be even or greater than the
summer’s bandwidth.
Bandwidth as a
Function of
Outside Temperature
Outside
T°
Winter
T°
Summer
T°
Winter
Bandwidth
Summer
Bandwidth
Bandwidths
of stages
1 & 2
Note that the ventilation stages’ start
temperatures will be adjusted following
the bandwidth fluctuations as the outside
temperature changes.
6.2.1.4. 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.
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 1 is reached (when
Time Off becomes less than 15 seconds, it
is fixed at 15 seconds until the temperature
has reached the set point + differential 1.
At that point, the fans of stage 1 operate
continuously).
Stage 1 Ramping
A
B
C
Stage 1
Differential
Min.Ventil.
Stage 1
Start T°
Room T°
Run Time
On Time =
Cycle Time
On Time
If the room temperature decreases 0.3°F
below the set point + differential 1, the
“On
Time”
value of the minimum ventilation cycle
decreases gradually from a value equal to the
total
“Cycle Time”
(point C) towards the regu-
lar
“On Time”.
Ramping Settings
To use the ramping function, disable variable
outputs in the Installation Setup (section
4.5) and adjust the differential of stage 1 in
section 6.2.2.
Settings
6.2.2.
6.2.2.1. Fan Stage Settings
Select:
1.
Current Conditions (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
Var 1 Summer Bdw 2.0
°F
Var 1 Winter Bdw 2.0
°F
Var 2 Summer Bdw 2.0
°F
Var 2 Winter Bdw 2.0
°F
Diff
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
Set the following parameters:
2.
(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.
Notes: Stage 1 stops when the room
temperature falls 0.3 °F below its start
temperature.
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.
V1 & V2 Bdw (Bandwidth) —
Set the number
of degrees required for variable fans to reach
their full speed in stages 1 and 2. If the “Outside
temperature compensation” function is used,
set these bandwidths separately for winter and
for summer (see sec. 4.5). *
Accessible if variable
outputs are assigned to fan stages (section 4.9).
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 6.2.1.3
The differential can be adjusted between
0.5°F and 20.0°F (0.3°C and 11.1°C). *
This
parameter is accessible if the ramping option is
enabled (i.e. if variable outputs are disabled in the
Installation Setup (section 4.5)).
Summary of Contents for Koolmaster PP20-VS2
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