9.9.Sensor functions
The wind velocities is output from 0 m/s. The response threshold is 0.3 m/s.
With wind velocities under 0.5 m/s the measured values wind direction are not output.
The maximum, minimum, and average values for the individual variables are calcula-
ted continuously by means of function channels Xmax, Xmin, Xavg, and the sensor-in-
ternal cycle of 2 seconds. To call up these values the required
output cycle
(2 seconds
to 24 hours) must be programmed in the device.
In the sensor menu the humidity fan can be switched off with a view to saving energy
and the station thus be operated on the ALMEMO
®
device with 12 V in energy saving
mode 1 (approx. 25 mA). The rain radar is then only tested once per minute and the
fan remains deactivated. If the 24-V mains unit is connected and automatic mode is set
the heating, fan, and radar are activated automatically as and when needed. The sensor
supply voltage can be checked in the display.
9.10.Limitations when operating without an external supply
If the Meteo Multi is operated without an external supply voltage, e.g. with an opera-
ting voltage below 12 VDC, the fan will - irrespective of the fan mode setting - not be
activated. This may in conditions of strong direct sunlight affect the accuracy of tem-
perature and humidity measurement.
9.11.Operating modes of the device heating
In the factory default settings the heating is configured to
AUTO
. This is the recom-
mended operating mode for heating the intelligent weather sensor system. The follo-
wing operating modes can also be set :
Automatic
In the 'automatic' mode the device is kept at a constant standard tempera-
ture in order to usually avoid the adverse effects caused by snow and ice.
Off
In the 'off' mode the heating is completely deactivated. In this mode winter opera-
tion is not possible because ice may prevent the rain sensor and wind measuring instru-
ments from functioning properly.
9.12.Operating modes of fan
In the factory default settings the fan is configured to
AUTO
.
Automatic
In the 'automatic' mode the fan is switched on and off on a cyclic basis.
OFF
In the 'off' mode the fan can be switched off with a view to reducing consumpti-
on and saving energy.
Advisory note
If the fan is deactivated the heating will also be deactivated (energy saving mode 1). If
the fan is deactivated this may in conditions of strong direct sunlight lead to discrepan-
cies in temperature and humidity measurement. (see chapter 9.13)
If the weather station is supplied directly via the measuring instrument, the fan will be
deactivated - irrespective of the setting AUTO / OFF setting. (see chapter 9.10)
In the AUTO setting the weather station will not switch to energy saving mode 1.
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