Calculation: the data-logger processes most of the meteorological data for the users (avg, min, max...). Data storage: the data-logger saves all the data either on its own memory or on uSD memory card. Power supply: the data-logger manages the power supply of the Automatic Weather Station, using a solar panel for instance. Communication: the data-logger manages the communication protocols with the remote server. The different communication protocols are usually GSM, GPRS, RTC, WiFi, uSD, and RS-232. Enclosures Enclosures used with automatic weather stations are typically weather proof fiberglass, ABS or stainless steel, With ABS being the cheapest, cast aluminium paint or stainless steel the most durable and fiberglass being a compromise. Power supply The main power source for an automatic weather station depends on its usage. Many stations with lower power equipment usually use one or more solar panels connected in parallel with a regulator and one or more rechargeable batteries. As a rule of thumb, solar output is at its optimum for only 5 hours each day. As such, mounting angle and position are vital. In the Northern Hemisphere, the solar panel would be mounted facing south and vice versa for the Southern Hemisphere. The output from the solar panels may be supplemented by a wind turbine to provide power during periods of poor sunlight, or by direct connection to the local electrical grid. Most automated airport weather stations are connected to the commercial power grid due to the higher power needs of the ceilometer and present weather sensors, which are active sensors and emit energy directly into the environment. Mast The standard mast heights used with automatic weather stations are 2, 3, 10 and 30 meters. Other sizes are available, but typically these sizes have been used as standards for differing applications. The 2 meter (6.6 feet) mast is used for the measurement of parameters that affect a human subject. The mast height is referenced to head height. The 3 meter (9.8 feet) mast is used for the measurement of parameters that affect crops (such as wheat, sugar cane etc.) The mast height is referenced to crop top. The 10 meter (32.8 feet) mast is used for the measurement of parameters without interference from objects such as trees, buildings or other obstructions. Typically the most important weather parameter measured at this height is wind speed and direction. The 30 meter (98.4 feet) mast is used for the measurement