用途：
DC3和DC4是DC1改进版本。钢丝绳的拉力改为径向设置。这样钢丝绳对树的压力和树径无关，不同树径的测量结果可直接比较。传感器通过一个由热膨胀系数低的合金制成的钢丝绳固定在树上。用小塑料环减少钢丝绳对树的压力，并减少摩擦阻力，大大提高灵敏度。
DC3和DC4的区别在于，DC4的测量范围比较大， 如果树杆比较粗或长得比较快，用DC4更合适。
应用
植物生长过程的监测
植监测物的水分状况。在以下方面：
-生态研究
-灌溉控制
环境因素对植物生长影响的研究
精准确定每年的生长季节开始和结束的具体时间。
精准判定霜冻事件的发生
植物水分和蓄水量的估算(结合液流量测量，可以连续计算蒸腾量)
监测和调查森林、道路和公园树木或树枝的稳定性
果蔬贮藏过程中水分的流失
多年生植物(例如树木)的典型植物生长曲线是什么样子的，它能告诉我们什么：
(右图)是连续测量的树木生长曲线。(A)连续数据揭示了直径增长动态的年际差异，即生长周期的开始和结束以及直径增长的速度(曲线斜率)。
在白天的时间尺度上(如图所示)。(B)直径变化过程显示出蒸腾耗水量高的时期，干旱时期表现为树干的强烈收缩和膨胀(高日径变化)。在降雨过程中，蒸腾耗水量是很小，茎秆内水分得到补充，如微弱的日茎秆变化和茎秆大小回归生长曲线(黑色的虚线图)所表明的那样。
特点：
·适合于直径大于> 5厘米的树；
·钢丝绳对树的压力和树径无关，不同树径的测量结果可直接比较；
·钢丝绳的拉力根据树径自动调整，反应敏感；
· 对植物无损伤；
·可抗拒风，雪，下跌小树枝和小果实的影响，保证稳定测量；
·易于安装；
·用花兰螺丝简化复调；
·数据必须经过换算才能取得周长变化（有免费Excel程序）；
· 测量的树干最好接近圆形；
·耗电少，比如用DL10 数采，一个内置普通电池可连续记录两年以上的数据；
· 有15年全球不同地带成功使用的经验（极地地区，热带，高山，沙漠）；
·分辨率高达0.03微米（取决于数采的分辨率）；
·探头温度补偿；
·与常用数采兼容，如Delta-T Logger， Campbell Logger， DataTaker Logger。
技术参数：
DC3周长生长测量传感器 | |
适用于树杆直径 | >5厘米 |
传感器测量范围 | 25.4毫米 |
复调测量范围 | 无限 |
一次测量范围 |
|
准确度 | ±（测量值的0.04%+0.6微米） (CR300 Logger) ±（测量值的0.1%+1微米） (DL18 Logger) |
分辨率 | 0.03-6微米（取决于使用的数采） |
线性系数 | <0.7% |
传感器的温度系数 | <0.1微米/度 |
钢丝绳热膨胀系数 | <1.4 ×10-6/K |
重量（仅传感器） | 37g |
传感器电缆长度 | 5m，可扩展至最大100m |
工作条件 | 温度范围 -25–70 °C, 湿度范围 0-100％ |
生长测量仪数采 | |
连接生长测量仪数目 | 1~4个 |
分辨率 | 0.3-0.6 微米（和生长测量仪的型号有关） |
内存 | 1 900 000个数据内存（连4个生长测量仪，每分钟测一次， 可存一年的数据） |
接口 | USB |
电池 | 一个内置电池可连续使用一年以上 |
防水 | 是 |
以下是来自厂家的一封Email：
Important product information: Deviation in quality of fastening elastic band DC and DDL
Dear Customer,
unfortunately, we have to inform you that in the case of the dendrometer products of the model series DC (DC3, DC4) and DD-L (DD-L1, DD-L2, DD-L3) there has been a quality deviation in the area of the fastening rubber bands. In this context, Unfortunately, we have now been told by some of our customers that the fastening rubber band on individual dendrometer devices of the above-mentioned model series does not correspond to the otherwise usual high quality, but rather begins to tear after a short period of use.
Affected are deliveries between March 1st, 2021 and August 15th, 2021.
You have received this letter because at least one of your this year’s orders of DC or DD-L dendrometers falls within the specified delivery period and may therefore be affected.
We apologize very much for this quality deviation.
However, since by far not all devices from the above-mentioned period are affected by the deviation, a general replacement of all rubber bands does not seem appropriate.
We therefore ask you to contact us if your customers, or you yourself as the end customer, should also notice such a defect in your DC or DD-L products.
We will then arrange for a replacement of the fastening rubber immediately.
Due to the far-reaching consequences of the Covid19 pandemic on global supply chains, we were unfortunately also forced to use alternative products from new suppliers in the case of a few components in our sensor products. Unfortunately, in such cases, even a detailed comparison of manufacturer specifications, as well as our additional tests carried out in-house, cannot entirely replace the many years of experience and meticulous selection of our usual components and well-known suppliers.
Thank you for your understanding and with best regards,
Michael Goisser
--
Dr. Michael Goisser
Sales Manager
Applications Scientist
ECOMATIK GmbH