EMS62Multi channel plant stem flow measurement system

The EMS62 multi-channel plant stem flow measurement system adopts the principle of stem heat balance (SHB) to continuously and accurately measure plant stem flow, which is the stem flow measurement method specified in the "Forestry Industry Standard of the People's Republic of China - Long term Positioning Observation Method for Forest Ecosystems" (LY/T1952-2011, implemented on July 1, 2011). The tree stem flow measurement system includes sensors, data collectors, software, and installation tools. Powered by batteries and equipped withhaveWaterproof functionYes, multiple sensors can also be selected to form a measurement and monitoring system, making the research more comprehensive and in-depth.The application field is basically the same as the EMS81 systemHowever, the EMS62 system is more suitable for slender stems and branches of treesOr stem flow measurement of crops. Therefore, the EMS62 system can also be used for physiological research on crop cultivation, as well as physiological research on tree hydraulic structure and water management allocation.

Working principle：

The EMS62 stem flow meter sensor includes a protective shell composed of a radiation resistant outer shell and insulating materials, ensuring that the thermal balance is not too disturbed when used indoors or outdoors. EMS62 is commonly used to measure plants or organs with a diameter less than 20mm, such as twigs, seedlings, and crops. When installing, it is important to ensure good contact between the detector and the stem surface.

The tree stem flow measurement system is based on the principle of heat balance (HB): the input energy is equal to the dissipated heat conduction and the increase in stem flow temperature. The specific formula is as follows:

In the formula, P is the input energy (W), Q is the stem flow velocity (Kg/s), dT is the temperature difference at the measurement point (K), and c_wSpecific heat of water (J.kg)^-1.K^-1）Z is the coefficient of thermal conductivity loss at the measurement point (W.K)^-1）.

The EMS62 measurement system has fixed dT,Make the heat lossConstant value, can be utilizedBaseline elimination.Calculating stem flow is not based on changes in temperature, but on changes in heating power.

Functional features:

Ÿ Forestry industry standard (LY/T 1952-2011) specifies measurement methods

Ÿ Using feedback control, the temperature difference between the upper and lower probes is automatically controlled to be constant

Ÿ The software can perform baseline calibration and directly output stem flow data

Ÿ Long term continuous monitoring, uninterrupted monitoring, no need for duty

Ÿ Equipped with protective devices, highly integrated, convenient for field installation and maintenance

Ÿ Optional sensors for temperature and humidity, solar radiation, soil moisture content, etc

Technical parameters:

1. EMS62/64 sensor

Applicable diameters: 6-12mm and 12-20mm

Heating technology: external soft elastic heater

Measurement module output: thermal power signal (mW/K)

Software output: Stem flow rate (Kg/h · cm)

Temperature sensor: specially designed thermocouple

Temperature difference: constant at 4K or 2K

Heater resistance: 100 ± 0.5 ohms

Heating current: Maximum 0.15A per channel (depending on stem flow rate)

Heating power: variable, maximum 2W (depending on stem flow rate)

Working temperature:- 10～40℃

Measuring branches: requires a length of 20cm

Weight: Sensor 0.1Kg

3. Data collector

8 channels; Accuracy: 0.03% of the measuring range; Storage capacity: 512KB, approximately 220000 values (can be used for more than 3 months); Data collection interval: 10-2 minutes; Storage interval: 10s-1hr

There are also 12 channels and 16 channels available for selection.

4. Software

It can run on various versions of Windows systems and can be downloaded and upgraded from the official website. Used for system settings, data storage, data analysis and processing, and output.

5. Power supply: 12V DC lead-acid battery or power adapter

Place of Origin:Europe

reference:

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