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Siemens Building Technologies
Basic Documentation RVA63.242, RVA53.242
CE1P2373E
Landis & Staefa Division
General control processes
26.03.2001
6.8 Composite outside temperature
Compensating variable for flow temperature control.
The composite outside temperature is a mixture of the actual outside temperature and
the attenuated outside temperature as calculated by the controller.
The mixture of actual and attenuated outside temperature is dependent on the type of
building construction (setting 113) and is generated as follows:
Selected type of construction
composite outside temperature
Heavy (setting 113 = 0)
Tagem = ½ TAakt + ½ TAged
Heavy (setting 113 = 1)
Tagem = ¾ TAakt + ¼ TAged
The composite outside temperature as a compensating variable acts on flow
temperature control, that is thus matched to the prevailing weather conditions.
It also acts on the 24-hour heating limit to shut down the heating.
13
14
15
16
17
2371D12
18:00
06:00
06:00
18:00
18:00
t
TA
TAakt
TAged
°C
TAgem1
TAgem0
TAakt
Actual outside temperature
TAged
Attenuated outside temperature
TAgem1
Composite outside temperature for light building structures
TAgem0
Composite outside temperature for heavy building structures
Benefit
Description
Process
Effect
Example
