Forced Aspirated Enclosure

This is my example of a “suitable” enclosure for the Air-data sensor group. The housing is constructed of fence post sleeve as found in home improvement stores etc. This particular product is made of recycled plastic and is completely hydrophobic. Incidentally the brand of material is called “Severe Weather”, kind of fitting for a weather station. Lowe’s carries this material and accessories, but other vinyl fencing material will work just as well and may be even cheaper.

It has the exact dimension to hold an electric fan snugly in place. For a small enclosure like this the fan is needed to continuously draw air from the top over the temperature and humidity sensor, without it the post would have to be a lot bigger to not heat up in sunlight. The 12 Volt fan is run of the 5V from the power supply and spins at a leisurely rate for a long life.

In this installation I opted to place the main board right inside the post. It is sitting on two rails in the top, above the upper line of holes to protect it from dust settling on it. The PCB is conformal coated in this case. A pyramid cap protects it from rain getting on it.

For more info on this see also the post on www.wxforum.net !