Vaisala CT25K - Troubleshooting; Warnings

Ceilometer CT25K
CT25K-U059en-2.1 User’s Guide
93
NOTE
The minimum distance to a hard target should be 300
meters (1,000 ft). The backscatter signal from a hard
target is very strong compared to the signal from a cloud.
The receiver may saturate if the distance is too short.
CAUTION
When tilting the unit, make sure that nobody is watching it
with binoculars or other magnifying optics.
Disable the automatic angle correction by giving commands :
CT> OPEN ↵
CEILO>SET MESSAGE ANGLE_COR OFF↵
CEILO>CLOSE↵
Compare ceilometer’s distance reading to a reference measurement.
7.2 Troubleshooting
The purpose of this troubleshooting is to locate the problem. If a damage is
suspected in a subassembly or a board, replace it with a spare part and send
the defective part to Vaisala for repair.
NOTE
Replacements have to be done according to instructions
given in the Instructions for Replacement of Parts in
section 8 and are allowed for trained personnel only. As a
principle, customer made repairs are restricted to
replacement of subassemblies only.
7.2.1 Warnings
Status message info Reason Instructions
Window contaminated
warning
(Appears from time to
time and lasts < 5 min)
Usually rain drops
on the window
The blower will clean the window.
If clouds are detected, the height
information is correct.
If no clouds are detected, it is
possible that high clouds are missed.
Window contaminated
warning
(Continuous)
Bird droppings,
leaves, dust etc.
have contaminated
the window
Clean the window