17
Bandwidth compensation
If the outside temperature is part of the installation, the bandwidth of the main ventilation and/or air inlet flaps
can automatically be adjusted to changes in outside temperature. As a result, it is possible to obtain a larger
bandwidth at low outside temperatures and a smaller bandwidth at high outside temperatures.
Current temperature outside = 10°C
Current temperature outside = 30°C
This setting is used to adjust the bandwidth to the current outside temperature.
Example bandwidth compensation:
Bandwidth
Bandwidth compensation
Bandwidth compensation starts at outside temperature:
4.0
-2.5
20
°C
%/°C
°C
At an outside temperature of 20°C the bandwidth is 4.0°C. If the outside temperature drops to 10.0°C the
bandwidth is increased by 1.0°C.
Δ
T = Current outside temperature-bandwidth compensation starts at outside temp. = 10.0°C-20.0°C= -10.0°C
Correction bandwidth = ((
Δ
T * Bandwidth compensation) * Bandwidth) / 100%
Correction bandwidth = (-10.0°C * -2.5%/°C) * (4.0°C / 100%) = 1.0°C
The corrected bandwidth is: 4.0°C + 1.0°C = 5.0°C
But if the outside temperature increase to 30.0°C the bandwidth will be diminished with 1.0°C to 3.0°C (4.0°C
- 1.0°C = 3.0°C).
The bandwidth is limited: the upper limit is 20.0°C; the lower limit is 1.0°C.
Compensation minimum ventilation
The minimum ventilation can be automatically adjusted to the actual outside temperature. As a result, a lower
minimum ventilation is obtained at low outside temperatures and a higher minimum ventilation at high outside
temperatures. This way, you are always ensured of a correct minimum supply of 'oxygen-rich' air.
The outside temperature at which the calculated minimum ventilation should be equal to the set minimum can
be set behind 'Start outside temperature'. The percentage at which the minimum ventilation should be corrected
per °C of change in outside temperature is set behind the “Compens. minimum ventilation”.
Example:
Minimum ventilation
20,0 %
Compensation minimum ventilation
1,0 %/°C
Start outside temperature
15,0 °C
Current outside temperature
5,0 °C
(5,0°C-15,0°C)*1,0%/°C*20,0%/100%=-2%
Calculated minimum ventilation (20,0-2,0)
18,0 %
Current outside temperature
30,0 °C
(30,0°C-15,0°C)*1,0%/°C*20,0%/100%=+3%
Calculated minimum ventilation (20,0+3,0)
23,0 %
The calculated compensation of the minimum ventilation will be valid for all ventilation groups.
Mi
n
im
u
m v
e
n
ti
la
ti
o
n
[
%
]
Outside temperature [°C]
5.0 30.0
15.0
15
20
10
25
30
0°C
30°C
40°C
3°C
0°C
6°C
1°C
2°C
4°C
5°C
7°C
8°C
20°C
10°C
C
o
rr
ect
ed
ba
nd
w
id
th [%
]
Outside temperature [°C]
Bandwidth diminished
from 4.0°C to 3.0°C
0°C
30°C
40°C
3°C
0°C
6°C
1°C
2°C
4°C
5°C
7°C
8°C
20°C
10°C
Outside temperature [°C]
C
o
rr
ect
ed
ba
nd
w
id
th [%
]
Bandwidth increased
from 4.0°C to 5.0°C
