Casella STORM Guardian 운영자 핸드북 매뉴얼 - 페이지 4
{카테고리_이름} Casella STORM Guardian에 대한 운영자 핸드북 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Casella STORM Guardian 10 페이지.
페이지 인쇄Principle of Operation
The rain gauges comprise a light weight injection moulded plastic divided .tipping
bucket. assembly with stainless steel pivot pins that rest upon stainless steel pins in
the support assembly. The use of pins produces a rolling rather than pivoting motion
when the bucket tips, which reduces the likelihood of friction.
Rain collects in one side of the bucket, which tips once a predetermined volume of
water has been collected. The tipping action discharges the collected water and
positions the other side of the bucket under the discharge nozzle ready for filling.
Each time the bucket is tipped, a magnet within the bucket moulding closes a reed
switch in the support assembly. The use of a sealed reed switch, capable of indefinite
operation, ensures the instrument has a long working life. Each contact closure pulse
represents a discrete amount of rainfall appropriate to the instrument's calibration.
These tipping pulses may be counted or recorded using a variety of methods, as
described in Chapter 6.
The tipping bucket mechanism is mounted inside the body on a cast aluminium-alloy
base, incorporating a built-in spirit level to facilitate correct positioning. Both body and
funnel are manufactured from aluminium alloy, with an accurately machined septum
ring with an aperture of 400 cm
. (200cm
version is now also available) The
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measurement accuracy for the various tip sizes is shown in Figure 2.
Figure 2: Accuracy of 0.1 mm, 0.2 mm and 0.5 mm tip versions
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