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© Retrotec 2017
The [Baseline] feature can be used to minimize the effects of Bias Pressures, including that caused by wind
if the wind is relatively constant. This will reduce remove the bias caused by constant wind from the
measurements but will not help with the fluctuating nature of wind which is the biggest issue.
[Baseline] exercise to practice minimizing the effects of wind
1.
Use a fan to create an air stream that causes between 2 and 5 Pa pressure.
2.
Set Time Averaging to one second.
3.
Place a tube, connected to the positive port, in the path of the air stream.
4.
Establish a Baseline pressure.
5.
Notice that once a Baseline pressure is taken, the measured pressure drops closer to zero,
negating the effects of the wind on the actual measured pressure.
6.
Stop the fan.
7.
Notice now that the measured pressure is negative, even though no pressure is being received
by the gauge. With the Baseline feature still active, the gauge is compensating for a pressure
that does not exist. Clear the baseline reading to eliminate this error.
8.15.5.
In extreme cases you can use a Wind Damping Kit designed to
reduce wind-related fluctuations
In extreme cases, wind-damping kits split the main pressure pickup point into either two or four directions,
which will average the fluctuation across the building. Recent experience has shown that longer time
averaging on a digital gauge is almost as effective as the four-tube wind damping kit. When the time taken
to set up the kit is taken into account, increasing the time averaging will actually save time.
A wind damping system averages out pressure fluctuations created by the wind yielding a more stable
pressure reading. In addition to a number of suggestions for obtaining better performance from a single
tube system, Retrotec offers two wind-damping kits specifically designed to reduce the pressure
fluctuations due to wind.
The basic wind-damping kit consists of a dual-tube pressure averaging system and will work in wind
conditions up to about 10 mph. The deluxe wind-
damping kit (our “Wild Wind Tamer”) consists of a four
-
tube engineered damping system that will provide damping results in winds up to 20 mph.
1.
Set up the house/room gauge and red tube as normal.
2.
Connect the open end to the T-connection on the basic wind-damping kit; connect the open
tube to the output port on the deluxe wind-damping kit.
3.
Place the wind-damping tubes away from the building to avoid the pressure pulse that gets
created when the wind hits the wall.
4.
Cover the end of the tubes with sheet material/a box to stop the wind, if required.
