Campbell Scientific CS725 Snow Water Equivalency Sensor - Manual (Page 29)

CS725 Snow Water Equivalency Sensor
• A delay will need to be typed in followed by the run time duration. It is
recommended to run the test for 1 or 2 hours; a value of 1 second can be
entered for the delay. A 1-hour test is 3600 seconds, so the following
would be typed in “1<space>3600<Enter>”.
• The CS725 will now monitor the gamma radiation for an hour.
• The .hr command can be issued several minutes into the test for
verification that it is running properly. The .hr command may take several
minutes to complete. Upon completion, the command will output the
current histogram (which can be captured to file for advanced diagnostics)
followed by the following lines.
-Elapsed time,current histo : 00:03:59
Pos K = 240.4; Pos Tl = 427.5;
Cnt K = 003679.8; Cnt Tl = 000088.3;
The first line indicates how long the CS725 has been monitoring. The
second line indicates the position of the potassium peak and its counts.
The third line indicates the position of the Tl peak and its counts.
It is important to record these numbers and refer to the radiation count
range in TABLE 8-2 and TABLE 8-3 for determining the suitability of
your site.
TABLE 8-2. Potassium (K) Count Range Guideline
Count Range
24 Hour K Count Range
1 Hour K
Recommendation
0 to 96000 0 to 4000 Insufficient K counts for CS725
SWE measurements.
96000 to 180000 4000 to 7500 Useable K count range for CS725
SWE measurements. May
experience larger errors for higher
SWE values.
180000 to 264000 7500 to 11000 Good K count range for CS725
SWE measurements. Should
maintain specified operating
characteristics.
264000 or greater 11000 or greater Excellent K count range for the
CS725 SWE measurements.
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