Operator`s manual

28
Installation, Operation and Maintainance of Buoy Operated Automatic Meteorological Stations
Sensors
and distilled water.
If condensation inside the wind shields still persists, remove the wind shields as described below:•
remove the mounting screws and the clamping rings1.
allow the condensation to escape or to evaporate for 15 minutes.2.
replace the wind shields while making sure that the O-rings are in their grooves before clamping the wind-3.
shields into place.
gently tighten the screws in the following sequence: first, third, fifth, second, forth, sixth. Continue the 4.
sequence until the windshields are evenly in contact with the clamping rings and frame.
tighten the screws in the same sequence until no space remains between the wind shield flange and the cor-5.
responding mounting ring. Do not over tight the mounting screws.
install an artificial snake on the support arm or tie two or three 8 inches cable to the support arm at the end 6.
near the sensor head with the free ends pointing upwards to form an array of spikes. This will discourage birds
from landing on the support arm or on the sensor head.
The sensor is recalibrated by the manufacturer and is therefore expected to show excellent stability over long 7.
periods. However, regular calibration checks are recommended. The sensor can be checked in the field by
mounting another Net Radiometer along side and comparing the results. Do not compare the readings with
sensors from different manufacturers.
Box 6: Caution While Cleaning the Solar Radiation Sensor
The surface of the silicon photovoltaic cell is sensitive to scratching. Handle the sensor with care while
cleaning. Only use a soft bristle. Never use hard or sharp materials for this purpose.
3.2.4 Trouble Shooting
Problem 1: Solar radiation values are zero.
Remedy 1.1: Check if all Q-7.1 wires are properly connected to the CR10X wiring panel. The reader is referred to
table 1 in paragraph 2.2 and Annex 2 for the correct wiring of the Q-7.1 to the CR10X.
Remedy 1.2: Re-load BUOY_METSTAT following the instructions given in paragraph 2.5.
Problem 2: Solar radiation measurements are in a range well below expected values.
Remedy 2: Carefully clean the sensor or remove any object that is shading it.
3.3 Vaisala HMP45C Temperature and Relative Humidity Sensor
3.3.1 General
The HMP45C Temperature and Relative Humidity Probe electronically measures both temperature and relative
humidity. It contains a platinum resistance temperature detector and a Vaisala HUMICAP capacitive relative humidity
sensor. The operating temperature is between –40C to +60C. The probe is programmed to take measurements at a
5-minutes interval. The datalogger places all daily recordings in a temporary memory, and this information is then
used to determine (a) hourly average temperature and relative humidity, (b) daily average temperature and relative
humidity, and (c) daily maximum and minimum temperatures. Only these values are stored in the logger’s Final
Storage Area, and the temporary memory is erased at the end of a recording day.
The HMP45C is powered by the CR10X 12V peripheral power terminal and draws less than 4 mA current while active.
To conserve energy, the datalogger is programmed to deactivate the HMP45C when the probe is not measuring.