非接触式测量雪水当量（SWE）
概览
通过探测从地表自然产生的电磁能量，通过积雪之后的变化，CS725来测量雪水当量（SWE）。CS725安装在地表上方，与积雪没有接触。当积雪厚度增加后，传感器由检测到地表发出的电磁能量的衰减，可以计算出SWE。CS725的测量面积为 50 到 100平方米，代表性大，因而是传统的雪枕传感器和量雪尺的卓越的替代传感器。
优势与特点
- 非接触式测量
- 完美替代传统雪枕测量方法
- 不会导致小雪的融化
- 极大地减少了访问现场站点的需要
- 不用准备现场或者设置现场的土方工程
- 性能不受降雨或降雪影响
- 对任何类型的雪或冰均有效
- 不会形成雪堆
- 7年无需维护
- 不适用抗结冰的化学物质（如乙二醇）
图像
技术说明
CS725使用12 Vdc供电，既可以独立工作，也可以轻松地连接到数据采集器。如果配上无线通讯选项，SWE数值可以从远程站点实时地传送出来。
产品规格
| Measurement Range | 600 mm maximum water equivalent |
| Accuracy |
|
| Resolution | 1 mm |
| Coverage Angle | 60° |
| Operating Temperature Range | -40° to +40°C |
| Power Requirements | 11 to 15 Vdc |
| Power Consumption | 180 mA |
| Output Options | RS-232 (1200 to 115200 bps) |
| Cable Type | Four conductor, two-twisted pair, 22 AWG, Santoprene jacket |
| Warranty | 2 years |
| Maximum Cable Length | 30 m (98.43 ft) |
| Diameter | 12.7 cm (5 in.) |
| Length | 62 cm (24.4 in.) |
| Main Body Weight | 9 kg (20 lb) |
| Collimator Weight | 25 kg (55 lb) |
| Total Weight | 34 kg (75 lb) |
兼容性
Please note: The following shows notable compatibility information. It is not a comprehensive list of all compatible products.
Additional Compatibility Information
Collimator Considerations
Other sources of electromagnetic radiation (40K) such as trees, vegetation, and buildings that are not covered by the same amount of snow as the ground can affect the readings. To filter these signals, the optional heavy steel collar (collimator assembly, pn 29390) is installed on the bottom of the CS725.
The following chart outlines when a collimator should be used:
| Site Characteristics | Maximum SWE 300 mm | Maximum SWE 300 to 400 mm | Maximum SWE > 400 mm |
|
Very open site with no proximity to trees, buildings, or tall vegetation within a 48 m (160 ft) radius |
Optional |
Optional |
Optional |
|
No trees, buildings, or tall vegetation within a 24 m (80 ft) radius |
Optional |
Optional |
Required |
|
No trees, buildings, or tall vegetation within a 12 m (40 ft) radius |
Optional |
Required |
Required |
|
Site with minimum clearance radius of 6 m (20 ft) radius |
Required |
Required |
Required |
Note: Always confirm that your sensor has the “Collimator Installed” parameter set properly. The SWE calculations are different for a sensor with and without a collimator.
常见问题解答
CS725: 5
展开全部收起全部
-
Yes, however the data would have to be back-calculated at the end of the season once all snow has melted, you would not have real-time SWE measurements.
-
The CS725 should be installed prior first snow fall to establish a good baseline reading. However, it can be installed after and the data back-calculated at the end of season. The only problem with this is you won’t have accurate SWE values during the season.
-
The sensor takes the measurement and outputs data in RS-232 format. If your data logger can receive RS-232 signals, it should work with the CS725. It’s also best that the data logger can measure volumetric soil moisture.
-
No, at this time the sensor does not output in SDI-12 format; however, it may be added in the future.
-
No, it only measures naturally emitted gamma radiation coming from the ground. The strongest signal of gamma comes from potassium-40 (40K).