TECH ST-408, Руководство пользователя, Страница: 16 / 28

ST-408 – user's manual
IV.e.7) Weather sensor (weather-based control)
To activate the weather function, external sensor should be placed in the
place which is not insolated and not exposed to atmospheric impacts. After
installation and connection, a sensor should have the function
Weather sensor
activated in a controller menu.
To make sure that the valve works correctly, the set temperature is set
(behind the valve) for four intermediate external temperatures:
TEMP. FOR -20
TEMP. FOR -10
TEMP. FOR 0
TEMP. FOR 10
Heating curve – this is a curve, according to which the preset controller
temperature is determined, on the basis of external temperature. In our
controller, this curve is constructed on the basis of three points of set
temperatures for the respective external temperatures. The preset
temperatures must be determined for external temperatures - 20ºC, -10ºC,
0ºC and 10ºC.
The more points constructing the curve, the greater its accuracy, which
allows its flexible shaping. In our case, four points seem to be a very good
compromise between the accuracy and the ease in setting the course of this
curve.
Where, in our controller:
X
A
= -20ºC, X
C
= 0ºC,
X
B
= -10ºC, X
D
= 10ºC,
Y
A
, Y
B
, Y
C
, Y
D
– preset valve temperatures for respective external
temperatures: X
A
, X
B
, X
C
, X
D
After activating the weather control, preset valve temperature
parameter is not available
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