Dynamax Inc Sap Flow Sensors & Soil Moisture Sensors

Optional Weather Sensors

Sensors for Soil

	THETA SOIL MOISTURE PROBE (type ML2) - This new probe measures soil volumetric water content to within ±2%. To measure soil moisture profiles or to monitor soil moisture continuously, the Theta probe can be added to almost any datalogger and buried at different depths. The output is 0 - 1 Volt and is very easy to convert to water content. The Theta probe performs well in a wide variety of soil types and gives accurate readings even under dry conditions.
	DISSOLVED OXYGEN SENSORS (Model OXG-H) – Oxygen Probes for measuring dissolved oxygen in soil. Model OXG is a Galvanic Cell, Self Polarizing, Self Temperature Compensating, 0-50 mg/l and has Pre-amp included, 0-60 mV DC Output, 10 ft Cable. Can be buried and requires no maintenance.
	TENSIOMETERS (SWT) - Ceramic cup, water filled tensiometers with pressure transducers. Shaft lengths from 300 mm to 2000 mm are available. These conventional tensiometers are well suited for irrigation monitoring, leachate studies and many other applications. They achieve an excellent ±0.2 kPa accuracy over a 0 to -85 kPa operating range. Ruggedized and miniature tensiometers are also available.
	EQUITENSIOMETER (Model EQ2) - The EQ2 is a wide range, low power, maintenance free probe based on the Theta probe mentioned above. The EQ2 performs well in dry soils - into the range where plant water stress is severe (water filled tensiometers cannot cover this range). The EQ2 accuracy is ±10 kPa from 0 to -100 kPa, and ±5% of readings from -100 to -1000 kPa.
	WATERMARK SENSORS (Model WMSM) - These granular matrix sensors can operate in drier soils than water filled tensiometers (up to -250 kPa). They are typically used when many replications are required and absolute accuracy is not a primary concern, as in irrigation monitoring for example. More dependable data can be collected if the Watermark sensors are installed alongside tensiometers or equitensiometers, which can be used to give benchmark readings. It is important to note that although both the Watermark and Gypsum Block sensors are inexpensive, the overall cost is increased by 1) their short life (usually 1-2 yr. depending on the number of freeze/thaw cycles) 2) the need to include an AC excitation current and 3) a device to read the AC output. A suitably specified DL2e datalogger can perform both functions.
	SOIL TEMPERATURE (Model TM-L10) - The TM10 is a rugged, accurate probe that measures air, soil, and water temperature in a variety of applications. These probes consist of a thermistor encapsulated in a epoxy-filled aluminum housing. The housing protects the thermistor allowing the probes to be buried or submerged. The TM10 measures from -35º to +50ºC. The TM10 Temperature Probe uses a thermistor to measure temperature. The standard lead length is 10 feet and custom lead lengths are available up to 1,000 feet. The TM10 Temperature Probe is designed for measuring air/soil/water temperatures. For air temperature, a 41301 radiation shield is used to mount the TM10 Probe and limit solar radiation loading. The TM10 is designed to be buried or submerged in water to 50 feet.

Sensors for Water

	DISSOLVED OXYGEN SENSORS (Model OXG-H) – Oxygen Probes for measuring dissolved oxygen in soil. Model OXG is a Galvanic Cell, Self Polarizing, Self Temperature Compensating, 0-50 mg/l and has Pre-amp included, 0-60 mV DC Output, 10 ft Cable. Can be buried and requires no maintenance.
	DEPTH SENSOR (Model PDCR1830) – The 1830 Series is the latest generation of fully submersible sensors which incorporate the most recent technical advances in depth & level measurement.
	OXIDATION / REDUCTION POTENTIAL SENSOR (Model DNX-ORP) - Water Oxidation / Reduction Potential sensor, preamp included.
	pH SENSOR (Model DNXPH) - 0 to 14 pH range, ±0.05 pH, can be used with most pH meters and dataloggers. The ISI response time is typically less than 10 seconds.
	CONDUCTIVITY AND TEMPERATURE PROBE (type 547-L20) - This probe measures electrical conductivity (EC), total dissolved solids, and temperature of water. Electrical conductivity is measured by three cylindrical electrodes mounted in an epoxy housing. Temperature is sensed with a thermistor. The 547-l20 is easy to clean and resistant to corrosion. It has rounded ends to ease installation and removal. It is suitable in most surface water, and industrial applications.
	RAIN GAGE (Model TE525) - The TE525 series tipping bucket rain gages are manufactured by Texas Electronics. The TE525 (6” orifice) measures in 0.01 inch increments. The gauge funnels precipitation into a bucket mechanism that tips when filled to a calibrated level. A magnet attached to the tipping mechanism actuates a switch as the bucket tips. The momentary switch closure is counted by the pulse-counting circuitry of Campbell Scientific data loggers.

Sensors for Air

	BAROMETRIC PRESSURE SENSOR (Model CS106) - The CS106 Barometer provides accurate, unattended measurements of barometric pressure from 500 to 1100 mb (approximately sea level to 12,000 feet). The CS106 is housed within the same enclosure as the datalogger, where it can be protected from the environment and kept desiccated.
	SOLAR RADIATION SENSOR (Model LI-200SZ) - The LI-200SZ Pyranometer is designed for field measurement of global solar radiation in agricultural, meteorological, and solar energy studies. In clear unobstructed daylight conditions, the LI200-SZ pyranometer compares favorably with first class thermopile type pyranometers (1, 2), but is priced at a fraction of the cost. Patterned after the work of Kerr, Thurtell and Tanner (3), the LI-200SZ features a silicon photovoltaic detector mounted in a fully cosinecorrected miniature head. Current output, which is directly proportional to solar radiation, is calibrated against an Eppley Precision Spectral Pyranometer (PSP) under natural daylight conditions in units of watts per square meter (w m-2). Under most conditions of natural daylight, the error is < 5%. The spectral response of the LI-200SZ does not include the entire solar spectrum, so it must be used in the same lighting conditions as those under which it was calibrated. Therefore, the LI-200SZ should only be used to measure unobstructed daylight. It should NOT be used under vegetation, artificial lights, in a greenhouse, or for reflected solar radiation.
	TEMPERATURE AND RELATIVE HUMIDITY PROBE (Model HMP50) - The HMP50, manufactured by Vaisala, measures air temperature with a 1000 ohm platinum resistance thermometer (PRT), and RH with the INTERCAP® capacitive chip. The chip is fieldreplaceable, as needed, and eliminates the downtime typically required for the recalibration process.
	WIND SPEED AND DIRECTION (Model 03001-L12) - The Wind Sentry Anemometer accurately measures wind speed. The small size, simplicity, and rugged construction provide a quality instrument for a modest price. This sensor interfaces directly with Campbell dataloggers; no signal conditioning is required.
	QUANTUM SENSOR (Model LI190SB) - Accurately measures Photosynthetic Photon Flux Density (PPFD) in both natural and artificial light. PPFD is the number of photons in the 400 to 700 nm waveband incident per unit time on a unit surface. Because PPFD describes photosynthetic activity, the LI190SB is ideal forgrowth chambers and greenhouses.