CS655 是多参数智能传感器，TDR时域反射法监测土壤体积含水量、容积电导率和土壤温度。它的信号输出方式为SDI-12，可用于大多数的 Campbell Scientific 数据采集器。探针长度比CS650更短，可以监测特高电导率的土壤，适合使用在基岩类土壤中。如果采用到ET107蒸散站的话请选用CS655-LC。
产品特点：
1.更大的采集体积，减少了误差
2.对土壤质地和电导率的影响进行测量修正
3.估算很多种矿质土类型土壤中的含水量
4.多功能的传感器 — 可测量介电常数、容积电导率（EC）和土壤温度
技术说明：
CS655由两个12厘米长的不锈钢棒连接到一个印刷电路板组成。电路板封装在环氧树脂中，并将屏蔽电缆连接到电路板上用于数据记录器连接。
CS655测量信号传播时间、信号衰减和温度。 然后从这些原始值中导出介电常数、体积含水量和体积电导率。 测量的信号衰减被用来校正反射探测和传播时间测量的损耗
效应。 这种损失效应校正允许在体积EC≤8ds m-1的土壤中精确测量水分含量，而无需进行土壤特定的校准。
通过衰减测量，计算了土壤的体积电导率。 热敏电阻与靠近环氧树脂表面的探针棒热接触，测量温度。 水平安装的传感器提供了准确的土壤温度用于计算测量在同一深度的土壤水含量。 如果采用其他方向安装，所测量的温度是靠近杆入口进入环氧体区域的温度。
Measurements Made | Soil electrical conductivity (EC), relative dielectric permittivity, volumetric water content (VWC), soil temperature | ||
Required Equipment | Measurement system | ||
Soil Suitability | Short rods are easy to install in hard soil. Suitable for soils with higher electrical conductivity. | ||
Sensing Volume（探测体积） | 3600 cm3 (~7.5 cm radius around each probe rod and 4.5 cm beyond the end of the rods) | ||
Electromagnetic | CE compliant (Meets EN61326 requirements for protection against electrostatic discharge and surge.) | ||
Operating Temperature Range | -50° to +70°C | ||
Sensor Output | SDI-12; serial RS-232 | ||
Warm-up Time | 3 s | ||
Measurement Time | 3 ms to measure; 600 ms to complete SDI-12 command | ||
Power Supply Requirements | 6 to 18 Vdc (Must be able to supply 45 mA @ 12 Vdc.) | ||
Maximum Cable Length | 610 m (2000 ft) combined length for up to 25 sensors connected to the same data logger control port | ||
Rod Spacing | 32 mm (1.3 in.) | ||
Ingress Protection Rating | IP68 | ||
Rod Diameter | 3.2 mm (0.13 in.) | ||
Rod Length | 120 mm (4.7 in.) | ||
Probe Head Dimensions | 85 x 63 x 18 mm (3.3 x 2.5 x 0.7 in.) | ||
Cable Weight | 35 g per m (0.38 oz per ft) | ||
Probe Weight | 240 g (8.5 oz) without cable | ||
Electrical Conductivity电导率 | |||
Range for Solution EC | 0 to 8 dS/m | ||
Range for Bulk EC | 0 to 8 dS/m | ||
Accuracy | ±(5% of reading + 0.05 dS/m) | ||
Precision | 0.5% of BEC | ||
Relative Dielectric Permittivity相对介电常数 | |||
Range | 1 to 81 | ||
Accuracy | · ±(3% of reading + 0.8) from 1 to 40 for solution EC ≤ 8 dS/m · ±2 (from 40 to 81 for solution EC ≤ 2.8 dS/m) | ||
Precision | < 0.02 | ||
Volumetric Water Content体积含水量 | |||
Range | 0 to 99% (with M4 command) | ||
Water Content Accuracy | · ±1% (with soil-specific calibration) where solution EC < 3 dS/m · ±3% (typical with factory VWC model) where solution EC < 10 dS/m | ||
Precision | < 0.05% | ||
Soil Temperature | |||
Range | -50° to +70°C | ||
Resolution | 0.001°C | ||
Accuracy | · ±0.1°C (for typical soil temperatures [0 to 40°C] when probe body is buried in soil) · ±0.5°C (for full temperature range) | ||
Precision | ±0.02°C | ||
