Vaisala LT31 - Page 265

Chapter 7 ___________________________________________________________ Troubleshooting
VAISALA ______________________________________________________________________ 265
P1:PWD; cleaning
required
The PWD sensor has evaluated
that cleaning is required.
Cleaning of optical surfaces within mid term
range. When cleaned, the CLEAN
command has to be executed at PWD
Sensor Menu (see section PWD Sensor on
page 241).
P2:PWD; immediate
cleaning required
The PWD sensor has evaluated
that immediate cleaning is
required.
Cleaning of optical surfaces is necessary.
When cleaned the CLEAN command has to
be executed at PWD Sensor Menu (see
section PWD Sensor on page 241).
P3:PWD; hardware
warning
The PWD sensor has evaluated a
hardware warning.
Execute Other Command STA at the PWD
Sensor Menu (see section PWD Sensor on
page 241 and refer to PWD User's Guide).
P4:PWD; hardware
error
The PWD sensor has evaluated a
hardware error.
Execute Other Command STA on the PWD
Sensor Menu (see section PWD Sensor on
page 241 and refer to PWD User's Guide).
P5:PWD; MOR not
valid
The MOR reading of the PWD
Sensor is invalid and can not be
used for auto-calibration purposes
Execute Other Command STA on the PWD
Sensor Menu (see section PWD Sensor on
page 241 and refer to PWD User's Guide).
P6:PWD; not
responding
PWD Sensor does not respond to
LT31 system polling request
Check whether the PWD Sensor lines
(power, RS–485) are connected properly.
PWD Sensor is not foreseen at all, but
PWD Sensor is configured to be available
(refer to Table 11 on page 150).
P7:PWD; not
installed
PWD Sensor is configured to be
not available (refer to Table 11 on
page 150).
–
R1:Receiver Main
Receiver LTD112;
DC high
R2:Receiver Main
Receiver LTD112;
saturated
A light source other than the
modulated transmitter signal is
detected at Main Receiver Module
site. Either the signal is detected
as high (R1) or the receiver is
saturated (R2).
Try to identify an additional light source of
any nature that might be in sight of the Main
Receiver Module.
If an artificial light source has been
identified try to eliminate the influence.
R3:Receiver Main
Receiver LTD112;
offset error
Main Receiver Signal is lower
than the underrange level.
During start-up this event is generated as
the average building is not complete.
Check whether the optical light path
between transmitter measurement unit
(LTM112) and receiver measurement unit
(LTM212) is unblocked.
Perform an Offset and Visibility Calibration
(see section Offset and Visibility Calibration
on pag
e 234).