Bringing the Benefits of Real-Time Data Collection to the World
Sutron Corporation, Tel: 703-406-2800,
http://www.sutron.com
153
CapRain (CapRain)
Inputs
<none>
Outputs
Rain
Wiring
Connect the sensor output to the selected analog channel.
Connect the sensor power to PROT 12 (B17) and GND (B16 or =)
Description
The CapRain block is designed to make measurements from an RM Young 50202 Capacitive
Precipitation Gauge. It may also work with other rain gauges with an analog output. The RM
Young 50202 sensor has an analog output (0-5 volts) corresponding to 0-50mm (0 to 2.5 inches)
rain. The sensor automatically empties itself so the output will periodically go to zero.
The CapRain block has special processing designed to prevent measurements while the gauge is
emptying the bucket. This processing takes two measurements of the gauge two seconds apart. If
the output drops by more than 0.1 volts in this two-second interval the system sleeps for 5
seconds and then tries again. Up to six retries will be performed before the system logs an error.
The block also has a special algorithm to accumulate the rain as though the bucket were not
being emptied. If the current value measured has gone down by 1/5 of the range since the last
measured value the software concludes that the gauge has emptied and adds 5*slope to the
sensor offset. The value reported by the block is always r offset.
Note: You must get data from the CapRain block every 10 to 15 minutes so it can track the
emptying. The maximum rain rate that can be handled by measurements every 10 minutes is
12 inches/hour and the maximum rate handled by measurements every 15 minutes is 8
inches/hour.
The block supports the calibration to a use entered current value. When the calibration function
is run, the system prompts for the current level. It then uses the current level and the current
reading to automatically set the offset. The calibration function should not be done when the
system is emptying the gauge or while the gauge output is changing.
Enter the slope in the units that you desire. The slope for inches would be 0.5 = 2.5inches/5volts.
The slope for mm would be 10 = 50mm/5.
The offset should normally be 0 for a new site with an empty gauge. As explained above, the
offset can also be computed to force the gauge to a specific value.
The units should be set to in or mm as determined by the slope.
Summary of Contents for Xpert2
Page 2: ......
Page 11: ...Chapter 1 Introduction...
Page 16: ......
Page 17: ...Chapter 2 Getting Started...
Page 86: ......
Page 87: ...Chapter 4 Graphical Setup Diagrams...
Page 104: ......
Page 105: ...CHAPTER 5 EXAMPLE SETUPS...
Page 128: ......
Page 129: ......
Page 130: ......
Page 131: ...Chapter 7 Installation...
Page 140: ......
Page 141: ...Chapter 8 Maintenance and Troubleshooting...
Page 145: ...Appendix A Setup Blocks...
Page 266: ......
Page 267: ...Appendix B Updating the Firmware...
Page 290: ......
Page 291: ...Appendix E Software Development Kit SDK...
Page 293: ...Appendix F Creating Custom Voice Files...
Page 330: ......