Our wind speed sensors have proven themselves in wind tunnel tests, in mountain-top tests and in thousands of household and institutional installations to be rugged, reliable and highly accurate.The type #41 generator has recorded wind to 214 mph. Their low moment of inertia and unique bearings permit very rapid response to gusts and lulls. The black lexan cups (virtually shatter-proof) have thermal propertieswhich let it resist and shed icing far more effectively than metal assem-blies. Because of their output linearity these sensors are ideal for use with various data retrieval systems. The experience that maximum hasbuilt up over the years has provided the basis of our solid confidencein these sensors for a wide variety of applications. Wind speed sensor 400 environmental Operating temperature: -67 to + 130 degrees f Operating humidity range: 10 to 100% rh Wind speed sensor 400 technical specifications * 3 cups of conical cross-section, 2" diameter. 7.5" swept diameter of rotor. * 2 diameter housing. * 3.2 overall assembly height. * moment of inertia of rotor assembly = 68 x 10-6 x s-ftâ². Material of cups is black lexan. * material of housing is black abs. * shaft material is beryllium copper; fully hardened. Upper and lower bearings of modified teflon, self-lubricating. * they have a rated pv factor of 20, 000 (at 15mph, pv is approx. 500; at 100mph pv is approx. 2, 000). * upper bearing is centered in the plane of cup thrust for optimal loading. * permanent magnet: indox 1, 1"dia. Long, 4 poles. Generators mount (using a cotter pin) on a 0.500" diameter mast with a #35 hole 0.350" from top of mast. * starting threshold < = 4 mph distance constant 10 feet