Chapter 4 _________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 99
Table 12 Default Factory Parameter Settings
Module modem (DMX501 only)
Contamination_compensation visibility_sensor
Contamination_compensation bl_sensor
Hood_heaters visibility_sensor
Dew_heaters visibility_sensor
Optional External Sensors
LM21 Background Luminance Sensor
The configuration command SET BL_SENSOR LM21 is used to add
the LM21 sensor output into the FS11P system and the data messages.
With this command, the interface unit CPU starts polling the LM21
sensor through the internal RS-485 sensor interface.
Day/Night Sensor
The Day/Night sensor (photo switch) output is measured and included
into the FS11P data messages with the configuration command SET
BL_SENSOR PHOTO_SWITCH.
A positive voltage is interpreted as a night condition and the background
luminance value in the FS11P output message is set to 0. Zero voltage or
an open circuit is interpreted as a day condition and the luminance value
is set to 1.