Campbell CS705, Instruction Manual

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CS705 Snowfall Adapter
2
3.1 Ships With
The CS705 is shipped with the CM270,
CS705 Mounting Kit
(pn 20621).
Refer to FIGURE 6-8 for information on positioning the various mounting
hardware.
The CM270 mounting kit includes the following:
•
(1) Band clamp (pn 20605)
• (1) Band clamp (pn 20606)
•
(1) Storage mount (pn 20636)
•
(3) Screws (pn 9580, 1/4-20)
• (2) Flat washers (pn 4365)
•
(2) Lock washers (pn 4366)
•
(2) Carriage bolts (pn 31922)
• (2) Wingnuts (pn 27552)
•
(1) Mast clamp (pn 27550)
•
(3) Grommets (pn 30838)
• (1) Bottom plate (pn 31917)
•
(1) V-shaped plate (pn 31413)
•
(1) S-shaped plate (pn 31414)
• (2) Springs (pn 20628)
•
(1) Spacer (pn 32009)
•
(3) Screws (pn 30978)
4. Overview
The CS705 is manufactured by Campbell Scientific and is based on the paper
“Measuring Winter Precipitation with an Antifreeze-Based Tipping Bucket
System” presented at the 1996 Western Snow Conference (McCaughey and
Farnes, 1996). The design possesses inherent delays and is not suitable for real
time precipitation measurements. Three design factors contribute to
measurement delays:
•
air / antifreeze mixture temperature
•
surface tension in the overflow tube
• precipitation form
All precipitation falling into the catch tube eventually flows through the overflow
tube and is measured by the tipping bucket gage. A delay of minutes is expected
for liquid precipitation so long as a minimum volume of water (≈0.03 inches) is
reached. A delay of several hours (up to tens) is expected for snow. Lightest
density snow at very cold temperatures has the longest delay.
The CS705 converts the TE525WS Texas Electronic Rain Gage, into a year-
round precipitation gage. The CS705 is intended for use only during winter.
Like any sensor, optimum performance is obtained by regular site visits. Any
antifreeze-based precipitation gage orifice is susceptible to capping or snow
bridging.
The CS705 is coated with a smooth black coating to minimize
surface adhesion and maximize solar loading, but snow bridging
may still not occur.
NOTE