Vaisala PWD22/52 - Visibility Value Too Good Troubleshooting; Visibility Value Too Low Troubleshooting

Chapter 7 ___________________________________________________________ Troubleshooting
VAISALA _______________________________________________________________________ 93
CHAPTER 7
TROUBLESHOOTING
This chapter describes common problems, their probable causes and
remedies, and provides contact information for technical support.
Common Problems
CAUTION
Servicing the equipment must be performed by qualified personnel.
Message Indicating Warning or Alarm
1. Open the command mode and check the status information with the
STA command (or poll Message 3 to get the same information).
- See section STA on page 73 for descriptions of the status
m
essage errors and warnings.
- Check the monitoring values against the internal monitoring
limits. See Appendix A, Values for Internal Monitoring, on page
103.
-
If the Backscatter increased warning is active (see section STA
on page 73), clean the lenses and remove possible disturbances
f
rom the optical path.
Message Missing
1. Does your terminal have the right settings?
- Change the baud rate, for example, to 9600 bps.
- Check that you have 7 data bits, even parity, 1 stop bits.
2. First give the
OPEN command (see section OPEN on page 49).
- Then give other commands to see if PWD22/52 is already in the
command mode.
3. Go to the site.