Vaisala LT31 - Table 33 LT31 PWD Status (Byte Number 40); Table 34 Background Luminance Sensor LM21 (Optional) Alarm Status Information (Byte Number 54)

Chapter 5 ________________________________________________________________ Operation
VAISALA ______________________________________________________________________ 173
The byte shown in Table 33 below indicates the status of the PWD
forward scatter sensor which is mounted to the transmitter support unit
LTS111 of the LTT111 (LT31 transmitter).
Table 33 LT31 PWD Status (Byte Number 40)
Code Explanation Comment
0 OK
I Indication of
abnormal
situation
Cleaning required.
W Warning Hardware warning.
A Alarm Immediate cleaning required.
E Error Hardware error.
C Communication
error
Device not responding.
X Not configured LT31 is not configured to handle
PWD (auto-calibration is off).
The byte shown in Table 34 below indicates the status of the LM21
Background Lum
inance Sensor which is optionally connected to the
receiver interface unit LTI211.
Table 34 Background Luminance Sensor LM21 (optional)
Alarm Status Information (Byte Number 54)
Code Explanation Comment
0 OK
I Indication of
abnormal
situation
Hood or dew heater problem.
A Alarm Sensor does not react to changes
in luminance.
LM21 has detected the field
calibrator LMA21.
Backscatter has increased.
E Error Memory error.
C Communication
error
Device not responding.
X Not configured LT31 is not configured to handle
LM21.