DDB Unlimited has a large selection of climate controlled enclosures. Here's an example of one of our recent projects using their enclosure.
IPVMU Certified | 11/18/15 07:17pm
Mier has a wide selection, too. They design to a modular standard, so you can swap active cooling units in the field without disrupting the rest of the cabinet.
We've done many, and have long considered wholesale'ing our wireless solutions, (another story but the first thing you need to do is determine your steady state power load in watts. The Box size minus the equipment space is the free space, and the enclosure makers have a color index for white, beige, gray, and direct sun or shade. This all gets you the heat rise value the wattage will create within the box above the outside temp. The bigger the box the lower the heat rise. Choose appropriate equipment for the temp range... All of the Nema enclosure makers have online heat rise calculators. We use -20c+70c equipment, with conformal coatings.
Avoid temperature / humidity / fans and filters on any outdoor box. A fully sealed 4 4X box is preferred, add pressure vents if the box is subject to drastic temp/humidity/heat wet cold changes....to avoid internal sweat.