Mike Suljak VA3LR wrote:
>> Does anyone know if there is a simple
>> conversion of Pascals to mph (or kph) ?
There isn't one. Pascals are units of pressure, while
mph and kph are units of wind speed.
1 Pa = 0.020885 lbs per square foot
The 550 Pa criterion is roughly 11.5 lbs/sq ft of pressure.
Basic wind pressure formula is 0.00256 V^2 where
V is wind speed in mph. If you solve for V, it
works out to 67 mph. This doesn't line up with
the 75/85/100 mph specifications.
You wrote that the Pascal numbers were with ice loading.
In the US standards ice loading is not done at ultimate
wind speed, it's at a lower speeds. Perhaps the Canadian
standards follow the same philosophy? The
75/85/100 mph loadings could be the ratings at ultimate
wind speed without ice. Ideally you'd want to choose
antennas that meet both the ice and no ice criteria.
Suggest contacting Trylon for their explanation.
73 Jim K6OK
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|