STATION OPERATION AND MAINTENANCE - Wind Resource Assessment: A Practical Guide to Developing a Wind Project - page 88

• Replace wind vanes and anemometers regularly as part of a preventive main-
tenance plan. A typical replacement schedule is once every two years. To
ensure continuity of the data record, replace only one of a pair of sensors at
the same height in a single visit.
• If any doubts arise concerning the stability of an anemometer's calibration, it
may be advisable to have the anemometer removed and recalibrated. Compar-
ing the pre- and postdeployment calibration coefficients allows any significant
drift in the anemometer response to be detected.
• Some anemometer types require periodic refurbishment such as ball bearing
replacement and recalibration.

2. Data Acquisition System
• Inspect the logger and the enclosure for signs of corrosion, damage, moisture,
and the presence of rodents or insects.
• Check the wiring panel to ensure a good connection to the sensors.
• Check battery voltage and replace batteries as needed.
• If the batteries are charged by a solar system, the solar panels should be

cleaned and their alignment checked and the panels, wiring, and electrical
connections should be examined for cracks and water resistance.

If a diesel or other generator is used, it should be tested and refueled.

•

6.2.4 Site Visit Procedures
All site visits should be carried out in three stages: in-house preparation, on-site tasks,
and site departure procedures.

1. In-House Preparation
• The field team should be informed of the reasons for the visit and the tasks
that need to be carried out. For example, is this a scheduled inspection and
maintenance visit or is it in response to a possible problem with the tower or
equipment? Will it be necessary to lower the tower to the ground or climb
it, or can the tasks be performed with access only to the equipment at the
tower's base?
• Where appropriate, the landowner should be informed of the visit in advance.
Aside from being courteous, maintaining good relationships with landowners
can help the wind project succeed over the long run.
• The team should be provided with a complete set of tools, supplies, equipment
manuals, and spare parts to accomplish all tasks. The Site Visit Checklist
(Section 6.3) specifies the required tools and supplies. This list should include
all equipment necessary to download the site data, such as laptop computers
with associated cables and special hardware.
• An extra memory card is a must, and it should be tested in-house before being
taken into the field. This is especially important when swapping memory cards