SFM1 Sap Flow Meter. The Heat Ratio Method

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1 The is a self contained, stand-alone instrument for the measurement of sap flow or transpiration in plants. The SFM1 is a complete package containing sap flow sensors, data logger, interface software and internal battery which can be charged with an external solar panel. The is a new model which replaces the HRM30 sap flow measurement sensor. Utilising the Heat Ratio Method (HRM) principle the SFM1 Sap Flow Meter is able to measure high, low and reverse flow rates in both small woody stems & roots as well as large trees. Like the Heat Field Deformation (HFD) principle, the HRM Sap Flow Meter is the only instrument that can measure zero flow and reverse sap flow rates. The SFM1 Sap Flow Meter is the most powerful and flexible instrument for the direct measurement of plant water use. Applications Low & Zero Sap Flow Rates Reverse Sap Flow Rates Night Time Water Loss Stem Sizes>10mm Sap Flow in Roots Arid Ecosystems & Drought Radial Sap Velocity Profiles Sap Flow of Grapevines Accessories include: SFT1 Sap Flow Tool Software MCC1 Wireless USB Radio communication device MCC2G Remote Data Access Hub for Data To Web access via GSM SFM-SK1 SFM Installation Kit SFM-55 Pack of 10 Drill Bits SFM-TB HRM block, Functional verification standard SP22 20 Watt Solar Panel and SPPM Solar Panel Post Mount The Heat Ratio Method Developed by the University of Western Australia and partner organisations, ICRAF and CSIRO, the HRM principle has been validated against gravimetric measurements of transpiration and used in published sap flow research since Burgess, S.S.O., et.al An improved heat pulse method to measure low and reverse rates of sap flow in woody plants Tree Physiology 21, Heat Ratio

2 Method (HRM) is an improvement of the Compensation Heat Pulse Method (CHPM). Being a modified heat pulse technique power consumption is very low using approx 70 mamp per day at a 10 minute temporal sampling interval under average transpiration rates. The HRM needles have two radial measurement points for the characterisation of radial sap flow gradients making measurements more accurate. and roots of a wide range of different species, sizes and environmental conditions including drought or water stress. Instrument design The SFM1 probes consist of three 35mm long needles integrally connected to a 16-bit microprocessor. The top and bottom probes contain two sets of matched and calibrated high precision thermistors located at 7.5mm and 22.5mm from the tip of each probe. The third and centrally located needle is a line heater that runs the full length of the needle to deliver a uniform and exact pulse of heat through the sapwood. Instrument Configuration & operation All aspects of the instruments operation and calculations are controlled by the microprocessor which automatically converts the analogue microvolt signals to a calibrated output. Programming variables such as heat pulse interval, energy input, probe spacings, and measurement frequency are all held resident in non-volatile memory. The HRM Sap Flow Meter displays information such as external battery status, Serial Number, firmware version, SD Card Status, Measurement interval, Data reporting options and correction factors. The utility software enables the Sap Flow Meter to be used in manual mode. This provides the ability to evaluate the efficacy of pulse intervals by viewing the raw measured temperatures on screen. Subsequent reports can then be viewed detailing the the duration of time the heat pulse required to deliver the exact amount of heat energy in Joules, the temperature rise following the previous heat pulse, temperature ratios between measurement points, sap velocity or sap flow. Through microprocessor control, the inner measurement point can be activated or deactivated dependent on the specific wood anatomy of the species being measured. This provides a great flexibility in stem diameter range from >10 mm diameter woody stems or roots to the world s largest trees, thus enabling water flows to be monitored in stems Data Analysis

3 Data can be manually processed using a spreadsheet program such as Excel to open the comma separated value (CSV) file provided by the Sap Flow Meter. More powerful and immediate processing can be achieved by directly importing the data file into the Sap Flow Tool Software. Thus providing instant 2 dimensional and 3D graphing of the raw heat pulse velocity and processing of sap velocity and sap flux. The entire data set can be instantly reprocessed if correction factors require modification or additional information becomes available.

4 Specifications MEASUREMENT Output Options Raw Temperatures: C Heat Pulse Velocity: cm hr-1 Sap Velocity: cm hr-1 Sap Flow: cm3 hr-1 (Litres hr-1) Range -100 to +100 cm hr-1 Resolution 0.01 cm hr-1 Accuracy 0.5 cm hr-1 Measurement Duration 120 seconds DATA Computer Interface USB, Wireless RF 2.4 GHz Data Storage MicroSD Card Memory Capacity Up to 16GB, 4GB MicroSD card included. OPERATING CONDITIONS Heat Pulse User Adjustable: 20 Joules (default) approx. Equivalent to a 2.5 second heat pulse duration, auto scaling. User Adjustable: Minimum interval, 3 minutes, recommended minimum 10 minutes. NEEDLE DESIGN Needle Diameter 1.3 mm Needle Length 35 mm Measurement Positions 2 per measurement needle Measurement Spacings 7.5 mm and 22.5 mm from the needle tip Dimensions L x W X D 170 x 80 x 35 mm Weight 400 g POWER Internal Battery Specifications 960mAh Lithium Polymer, 4.20 Volts fully charged External Power Requirements Bus Power 8-30 Volts DC, non-polarised, current draw is 190mA maximum at 17 volts per logger USB Power 5 Volts DC Internal Charge Rate Bus Power 60mA 200mA Variable internal charge rate, maximum charge rate of 200mA active when the external voltage rises above 16 Volts DC USB Power 100mA fixed charge rate

5 Internal Power Management Fully Charged Battery 4.20 Volts Low Power Mode 3.60 Volts Instrument ceases to take measurements Discharged Battery 2.90 Volts Instrument automatically switches off at and below this voltage when no external power connected. Battery Life varies With a recommended power source connected, operation can be continuous. Approximately 1.5 days with a heat pulse of 50 Joules and a measurement interval of 30 minutes no external power present to recharge battery.

6 Accessories CH24-24 Volt Power Supply The CH24 is a Volts AC Mains to 24Volts DC power supply adapter; capable of outputting up to 2.5Amps. For most ICT Instruments. ICT CIS - Cloud Data Analysis and Display The ICT CIS and DataView. ICT Universal Telemetry Hub ICT Universal Telemetry Hub MCC Mini The MCC Mini is a simple to use USB Serial to Radio Communications device providing a high level of integrity in data transfers. Its miniature design and minimalist approach make it an attractive solution for portable computers and less intrusive workstation setups where space and weight are of concern. Data to the Web Wireless Communication Module - Includes; MCC Radio Frequency Logging Hub, Comms and ICT Data View Software, GSM/2G/3G modem, 3V 5Ah Lithium Polymer Battery, 11W solar panel, IP66 enclosure.

7 Accessories Wireless Communication Wireless USB Radio communication device. Wireless Data Collector Wireless data logger. 4GB SD Card storage. Communicates with any ICT International instrument. Includes SPBP07 power supply. SFM-SK1 Installation kit SFM-SK1 Installation kit SFM-DR Dremel 8000 Dremel 8000 for SFM1 installation Sap Flow Tool Sap Flow Tool software for HFD and HRM. Single License. Unlimited access to any number HRM or HFD datasets. Configured to analyse HRMx, CHPM, Tmax data from the SFM Sap Flow Meter. Visualise PSY1, soil moisture, and meteorological data.

8 Accessories SP22-20 Watt Solar Panel SP22-20 Watt Solar Panel with 4m cable suitable for powering our SFM1, PSY1, HFD, SOM1, SMM1 etc products. The HRM Test Block The HRM Sap Flow Meter Test Block is a functional verification standard for use with the HRM Sap Flow Meter. Powered by TCPDF (