Weather Sensors

AIR TEMPERATURE & RELATIVE HUMIDITY   YES-H-ATRH-01

This is a rugged, accurate Temperature/RH probe manufactured with high precision sensing elements, ideal for long-term, unattended applications. The probe uses a MEMS based capacitive & resistive elements to measure RH and Temperature respectively. To reduce the current drain, power can be supplied only during measurement when the sensor is connected to the data logger’s switched suppy terminal. For optimum results, the YES-H-ATRH-01 should be recalibrated annually.

This sensor integrate sensor elements plus signal processing in compact format and provide a fully calibrated digital output, guarantees excellent reliability and long term stability. Both sensors are seamlessly coupled to a 14 bit analog to digital converter and a serial interface circuit. This results in superior signal quality, a fast response time and insensitivity to external disturbances (EMC). YES-H-RS radiation shield is recommended to be used when the sensor is exposed to sun light.

*Fully Calibrated

*Excellent Long-term Stability

*Digital Output

*Very low power consumption

*Easy integration

*Sensor with Radiation shield

AT Measurement range: -40 oC to +60 oC

Sensing element : MEMS

Resolution : 0.01 oC

Accuracy : ± 0.1 oC

Output: Digital/Analog


RH Measurement range: 0 to 100% non-condensing,

Sensing element: MEMS based capacitive element.

Operating @ -40 oC to +60 o C

Resolution : 0.1%

Accuracy at 20°C against factory reference: 1%RH

Field-calibrated against references : 2% RH ( 0 to 90% RH); / 3% RH (90% to 100% RH )

Temperature Dependence : 0.05% RH / oC

Long-Term Stability: Typically, better than 1% RH per year.

Response Time : <15 seconds with membrane filter ( at 20 oC, 90% response )

Settling Time: 500 milliseconds

Output: Digital/Analog

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RAIN FALL   YES-H-RF-01-FRP/SS

Tipping bucket rain gauge is used for automatic measurement of rainfall. Rain Gauge consists of twin buckets mounted on a horizontal shaft. It has two stable positions. The collector area of the rain gauge is 201 cm2. The rainfall collected by the receiver reaches to one of the twin bucket through a funnel. Thus a volume of 20.1 cm3 corresponds to 1 mm of rainfall, or equivalent to two full buckets. It measures the rainfall with a least count of 0.5mm and gives out two electrical pulses for every millimeter of rainfall. The weight of 10.05 cm3 of rainfall causes the tilting of the bucket from one stable position to another stable position and brings the other bucket under the funnel for collecting rain water. Every time the bucket tilts, the small magnet attached to the horizontal shaft of the bucket actuates a reed switch generating one electric pulse. Facility for leveling the bucket for proper calibration, a screen in the funnel to prevent debris from entering the gauge are also provided.

Fully Calibrated Excellent Long-term Stability

Sensing: Magnet with reed switch mechanism

Resolution: 0.5mm

Accuracy: Better than 1 mm

Sensitivity : 0.5 mm ( rainfall per tip)

Operating Temperature: 0 o to 70o C

Rim Diameter : 160mm

Collecting Area: 20114.286 mm2

Material : Gauge shell- FRP/SS; Rim ring - Gunmetal/Brass; Base - Aluminum alloy casting; Bucket- ABS material;

Capacity : Unlimited

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LEAF WETNESS   YES-H-LW-01

Leaf wetness sensor is used to monitor the level of surface moisture on foliage.

Sensor type : Resistive Grid

Resolution : 1

Measuring range : Scale of 0 ( Completely dry ) - - 10 (Saturated) of Surface moisture

Accuracy : ± 5%

Output : Analog / Digital

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WIND SPEED   YES-H-WS-01

This is a rugged, high performance, high resolution, low threshold opto electronic anemometer. Its simplicity, rugged and corrosion resistant construction make it well suited for a wide range of wind measuring applications. When rotated by wind, a chopper on the anemometer shaft interrupts an infra red light source, generating pulses from a photo transistor device. The signal is amplied and fed through a line driver.The frequency is proportional to wind speed.

*Fully Calibrated

*Digital Output

*Excellent Long-term Stability

*Easy integration

Sensor: 3 cup rotor with opto coupled pulse generator

Starting threshold: 0.3 m/s

Range : 0 to 65 m/sec

Distance constant: 2.5 Meters

Output: TTL/Digital

Accuracy: Better than 0.5 m/sec up to 10 m/s, ± 2% FS above 10 m/s

Operating Temperature: -40 o to + 60 o C

Sensor body: Anodized aluminum housing, stainless steel shaft and aluminum cups.

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WIND DIRECTION   YES-H-WD-01

This is a high performance, counter balanced, low threshold and rugged wind vane. It is built upon a linear, wire wound endless potentiometer coupled to the vane by an SS shaft mechanism. This potentiometer has excellent linearity, very low starting torque. The north of the wind vane is marked on its body corresponding to 0 degrees, and also resistance of 20 ohms approximately. The resistance output is linearly proportional to the position of the wind vane.

*Fully Calibrated

* Excellent Long-term Stability

*Digital Output

*Easy Integration

Sensor: Vane coupled to linear endless potentiometer

Staring threshold : Better than 0.5 m/s

Range : 0 to 359 degrees

Output: Analog / Digital

Resolution: 1 degree

Accuracy: ± 3 degrees

Operating Temperature: -40 o to + 60 o C

Sensor body: Anodized aluminum housing, stainless steel shaft and aluminum vane.

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SOLAR RADIATION   YES-H-PY-01

This Pyranometer is designed for field measurement of global solar radiation ( 400-110 nm) in agricultural, meteorological, and solar energy studies. The YES-H-PY-01 features a silicon photovoltaic detector mounted in a fully cosine-corrected miniature head. Current output, which is directly proportional to solar radiation, is calibrated against a primary standard pyranometer (Eppley Precision Spectral Pyranometer 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 YES-H-PY-01 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, it 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.

*Fully Calibrated

*Excellent Long-term Stability

*Digital Output

*Easy integration

*Cosine Corrected

*Blue enhanced

Sensitivity: Typically 90 µA per 1000 W m-2.

Linearity: Maximum deviation of 1% up to 3000 W m-2.

Stability: < ± 2% change over a 1 year period.

Response Time: 10 µs.

Temperature Dependence: ± 0.15% per o C max.

Cosine Correction: Cosine corrected up to 80o angle of incidence.

Azimuth: < ± 1% error over 360o at 45o elevation.

Tilt: No error induced from orientation.

Output: Analog / Digital

Detector: High stability silicon photovoltaic detector (blue enhanced).

Sensor Housing: Weatherproof anodized aluminum case with acrylic diffuser and rust resistant hardware.

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ATMOSPHERIC PRESSURE   YES-H-APR-01

This is a rugged, high performance, high resolution, pressure transducer built around ceramic MEMS sensing element to measure absolute pressure variations in the atmosphere in the range of 600-1100 m bar. The pressure transducer is provided with built-in signal conditioning with temperature compensation for generation of output signal proportional to prevailing pressure at the point of measurement. The sensor is well suited for remote applications such as in automatic weather stations, atmospheric research etc.

*Fully Calibrated

*Excellent Long-term Stability

*Digital Output

*Easy integration

*Interchangeable

*Low power consumption

Pressure transducer: Ceramic MEMS sensing element (Absolute)

Pressure range : 600 to 1100 m bar

Excitation : 9 V to 14 V DC

Resolution : 0.1 mbar

Accuracy : ± 0.2 mbar

Output units : hPa / mbar / custom

Operating Temperature : -20 o C to + 60 oC

Sensor output : RS-485 Serial Interface

Mechanical interface: Open diaphragm, hermetically sealed

Material of construction: ABS / Anodized Aluminum

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EVAPORATION   YES-H-EVP-01

An evaporometer is an instrument used to measure the amount of water lost by evaporation per unit area at a given interval of time. The values of evaporation give a measure of evaporative power of the air layers near the ground. U.S.W.B. Class ‘A’ Open Pan Evaporometer with electronic sensing facility as per IS: 5973:1970 is manufactured from painted GI sheet tested for water leak proof ness. . This is supported on wooden platform and covered with reinforced chickon, F For manual observations, the stilling well , thermometer with and measuring jar are optionally supplied for verification.

Made out of Material : Galvanized Iron / Cupper of 20 Gauge

Place of instrument: Above the ground surface, on a wooden frame

Diameter of the pan : 1220 mm

Height of the pan : 300 mm

Placement of stilling well / water level sensor: Inside the pan

Crop Co-efficient factor : 0.5 to 1.3

Rate of evaporation measured : At free surface

Units of measurement: mm of water

Output: Analog / Digital

System Accuracy: Evaporation gauge with pan and pipes ±0.25 percent over 10" (254mm) range

Specifications

0-10 Saturated Soil. Occurs for a day or two after irrigation.

10-20 Soil is adequately wet (except coarse sands which are drying out at this range)

30-60 Usual range to irrigate or water (except heavy clay soils). Irrigate at the upper end of this range in cool humid climates and with higher water-holding capacity Soils.

60-100 Usual range to irrigate heavy clay soils

100-200 Soil is becoming dangerously dry for maximum production.

Measuring range: 0 to 200 c Bar

Resolution : 0.01 c Bar

Accuracy : 0.1 c Bar

Output : Analog / Digital

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SOIL TEMPERATURE   YES-H-ST-01

This high performance Thermistor Probe of NTC Thermistor are ideal for making accurate measurements of temperature. They can be used for making measurements of air, soil, and water temperatures using appropriate conducting material.

Measuring range: 0 to + 80 o C

Resolution : 0.01 o C

Accuracy : 0.1 o C

Depths of measurement: 3 ( 5 cm, 10 cm, 20 cm depths )

Output : Analog / Digital

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SOIL MOISTURE   YES-H-SM-01

Soil moisture sensed using a Watermark type granular matrix sensor where-in an indirect, calibrated method of measuring soil water followed. It is an electrical resistance type sensor, which converts the electrical resistance reading to a calibrated reading of Centibars (or kPa) of soil water tension. It does take some time (weeks) for the soil moisture readings to stabilize to the surrounding soil.

Soil Moisture in cBar & Soil Condition table

Measuring range: 0 to + 80 o C

Resolution : 0.01 o C

Accuracy : 0.1 o C

Depths of measurement: 3 ( 5 cm, 10 cm, 20 cm depths )

Output : Analog / Digital

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SOIL HEAT FLUX   YES-H-SH-011

Heat flux sensor measure the rate of energy transferred through a given surface. The sensor is of several thermocouples whose measurements are averaged, a thermopile, or a thermopile with a film heater. This sensor provides soil heat flux measurements – typically for energy balance or Bowen ratio flux systems, intended for applications that do not require self calibration. It outputs a voltage signal that is proportional to the heat flux of the surrounding medium. At least, a couple of sensors are required for each site to provide spatial averaging. Sites with heterogeneous media may require additional sensors.

Sensor Type: Thermopile

Sensitivity (nominal): 50 µV W-1 m-2

Nominal Resistance: 2 W

Sensor Thermal Resistance: <6.25 x 10 -3 Km2 W-1

Range: ±2000 W m-2

Expected Typical Accuracy (12 hour totals): within -15% to +5% in most common soils

Output proportional to local heat flux. ( Analog)

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LEAF TEMPERATURE   YES-H-LT-01

Sensor type: High precision Thermistor / Thermocouple based sensing device

Measuring range: 0 to +65 o C

Resolution : 0.01 o C

Accuracy : 0.1 o C

Output : Analog / Digital

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QUANTUM SENSOR (PAR)   YES-H-Q-01

YES-H quantum sensors designed to measure photo synthetically active radiation ( PAR ) received on a plane surface, in the 400 to 700 nm waveband. The unit of measurement is micromoles per second per square meter (µmol s-1 m-2) or µEs-1 m-2.

A silicon photodiode with an enhanced response in the visible wavelengths is used as the sensor. A visible band pass interference filter in combination with colored glass filters is mounted in a cosine corrected head. Error calculations indicate that under sun-and-sky radiation, and various natural or artificial light sources found in environmental research, the relative errors are less than ± 5%.

Typical applications for this sensor are of measuring PAR within plant canopies, greenhouses, controlled environment chambers, confined laboratory conditions, or at remote environmental monitoring sites.

Specifications:

Absolute Calibration: ± 5% traceable to NIST.

Sensitivity: Typically 5 µA per 1000 µmol s-1 m-2

Linearity: Maximum deviation of 1% up to 10,000 µmol s-1 m-2

Stability: < ± 2% change over a 1 year period.

Response Time: < 20 µs.

Temperature Dependence: ± 0.15% per oC max.

Cosine Correction: Cosine corrected up to 80 o angle of incidence.

Azimuth:

Detector: High stability silicon photovoltaic detector (blue enhanced).

Tilt: No error induced from orientation.

Size: 2.5 Dia x 2.6 cm Height

Weight: 90 g

Cable length: 3 m (10 ft) standard.

Accessories: Mounting & Levelling Fixture

Sensor Housing: Weatherproof anodized aluminium case with acrylic diffuser and rust resistant hardware.

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LINE QUANTUM SENSOR   YES-H-LQ-01

Line Quantum sensor is designed for measuring PAR ( Photosynthetically active radiation) in applications where the radiation to be measured is spatially non-uniform ( as in plant canopies). To achieve this, sensor features a sensing area of one meter in length.

Line Quantum sensor has the quantum ( Photon) response through the wavelength range of 400-700 nm for PPFD ( Photosynthetic photon flux density) as preferred for PAR measurements, output units are in moles with the following relationship.1 µmol s-1 m-2 = 1 µE s-1 m-2 6.02 x 10 17 photons s-1 m-2.

YES-H Line Quantum Sensor, which spatially averages radiation over its 1 meter length, minimizes the error and allows one person to easily make many measurements in a short period of time. The sensor is sealed against moisture, however, water does not pool around the sensor. It is advised to used Quantum Sensor (Point type ) for precise absolute measurements above the canopy are desired.

Spectral Response: It is comparable to that of the Quantum Sensor ( Point type). Our quantum sensors use computer tailored filter glasses to achieve a response that closely approximates the desired ideal quantum response.

Surface Variation Errors: The response uniformity along the 1 meter length of sensor is specified to vary less than ± 6% when tested with a beam of light that is 3 cm in width. It is determined by the diffuser and internal optical design mechanism.

Specifications:

Same as YES-H-PAR except

Absolute Calibration: ± 10% traceable to NIST

Sensitivity: Typically 8 µA per 1000 µmol s-1 m-2

Sensing Area: 1 meter L x 14 mm W

Size: 120 L x 2.6 W x 2.6 cm D

Weight: 2.0 Kg.

As a total solution provider, we can configure scalable weather monitoring systems (AWS, AWOS, & ASOS) using our wide range of sensors, data loggers and Remote Data Access (RDA) software. If you are looking for a sensor that is not on our list please (contact our office), we will be glad tohelp you find the sensor you need.

YES ------Sensors, Instruments, Systems for Agronomy, Meteorology, Hydrology & Environment monitoring.

YASASWY Electronic Systems

While having technological tie-up with M/s. HEXATRIK Electronics, all sensing solutions are built around Embedded Computing Systems with in-house developed meteorological sensors, offer certain unique advantages to the user. While reliability and accuracy are the primary benefits, high speed processing, ruggedness are the other advantages.

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