4-20mA Environmental Monitoring Probe Sets
Aegis Sales & Service has a range of Weather Sensor Transmitters available which use the industry standard 4-20mA output signal [loop powered]. This allows for easy integration into a SCADA or PLC monitoring system.
Weather Sensor Transmitters [or Weather Stations] are tools for the observation and recording of meteorological data. The sensor can monitor air temperature, humidity, barometric pressure, light energy, wind speed and wind direction.
The sensors can monitor for: air temperature, humidity, barometric pressure, light energy, wind speed and wind direction
These sensors can be assembled onto T or L bar Equipment Arms.
Anemometers
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The Anemometer is used for the measurement of wind velocity. The TruTrack Anemometer is manufactured from stainless steel and anodized aluminium so as to provide minimum maintenance and maximum reliability.
Three Cup Anemometer specifications:
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The Anemometer can be supplied with a 4-20mA Output or Pulse [switch closure]. The Anemometer is supplied attached to the T Bar Equipment Mounting Arm [Shown left]. Options are available to supply free standing or on a base mounting plate [as per top image] for attaching to posts or buildings. A six-cup Anemometer is also available if your application requires lower starting speeds. |
| 3 Cup Anemometer | 6 Cup Anemometer | |
| 4-20mA Output: | 4-20mA Output: | |
| 4mA = 0 metres/second | 4mA = 0 metres/second | |
| 20mA = 60 metres/second | 20mA = 80 metres/second | |
| Order code: INWS3-CL | Order code: INWS6-CL | |
| Pulse output: | Pulse output: | |
| 2 pulses = 1 metre of wind run | 3 pulses = 1 metre of wind run | |
| Order code: INWS3-PS | Order code: INWS6-PS | |
Wind Vane
The Wind Vane is manufactured from stainless steel and anodized aluminium so as to provide minimum maintenance and maximum reliability.
The Wind Direction Vane has a 4-20mA output:
The Wind Direction Vane is supplied attached to the T Bar Equipment Mounting Arm. Options are available to supply free standing [as shown] or on a base mounting plate for attaching to posts or buildings.
Wind Vane Specifications:
- Range 0º-360º
- Accuracy ±5%
- Dead Band 20º [350º - 10º]
Light Energy Sensor
The Light Energy Sensor [Pyranmeter] has been designed to provide a wide spectral response, a good cosine response and low susceptibility to inaccuracies caused by raindrop and dirt effects. The Light Energy Sensor is supplied attached to a T Bar Equipment Arm. Options are available to supply freestanding, or on a Base Mounting Plate as shown.
Light Energy Sensor Specifications:
- Range 0-1500 w/m2
- Accuracy ±5%
- Cosine error is typically less than 3% from vertical to 85º in all directions
- Temperature Coeffiient 0.15% per 1ºC
The Pyranometer uses a polycrystalline silicon solar cell to measure the incoming global solar radiation. This gives good accuracy without the expense and maintenance required by a Thermopile Pyranometer. It also provides a flatter spectral response that the photo diodes that are frequently used for this type of sensor.
The Pyranometer has a relatively large surface compared to many photo diode sensors. The minimises inaccuracies caused by the effect of rain drops and dirt on the surface. The sensor has a slightly domed top to facilitate rain drainage. Dirt sitting on the surface of the sensor is dispersed by rain flowing off the dome.
Solar Radiation Shield - Model THP-CL
The Solar Radiation Shield is a chamber made from a series of fins that use the natural convection of warm air to draw fresh air into the chamber and expel the heated air. Temperature, Humidity and Pressure Sensors that are placed within the chamber will experience a flow of fresh air and so give more accurate measurements than sensors that are exposed to direct sunlight.
The fins are made from spun aluminium that has been powder coated white.
The Solar Radiation Shield is connected to the T Bar Equipment Arm. This is the most convenient way of mounting the shields to a tower, post or building.
The ventilated chamber within the Solar Radiation Sheild is cylindrical in shape, 90mm high and 50mm in diameter. This chamber is surrounded by a stainless steel mesh grill to protect the sensors from insects and windblown debris.
If sunlight falls on the sensors they absorb radiant energy directly from the sunlight and are therefore at a higher temperature than the surrounding air. This causes erroneous readings.
If the sensors are put into a chamber so that the direct sunlight can not strike them but the chamber and the air within it are heated this will also cause erroneous readings. If the chamber can be ventilated so that the heated air in the chamber can rise and escape through convection then fresh air from the outside will be drawn in over the sensors and accurate readings of the air temperature, humidity and pressure can be made.
Humidity Sensor
The HUMIREL HS1101 Humidity Sensor provides:
Instantaneous de-saturation
Solid polymer structure
High resistance to chemicals
Fast response time
Range 0% - 100%
Accuracy RH ±5%
The Humidity Sensor is housed inside the Solar Radiation Shield
Temperature Sensors
The Temperature Sensor is a high accuracy thermistor that has been factory calibrated to within 0.2ºC. This alleviates the need for any user calibration. The sensor has low thermal mass so as to ensure a fast response time.
- Temperature Range: -30ºC to 70ºC
- Accuracy: ±0.3ºC from [0ºC to 50ºC]
- The Temperature Sensor is housed inside the Solar Radiation Shield
Weather Station Accessories
TBar
The T Bar is specifically designed to give good separation between wind speed Anemometers and Wind Vanes. The total length of the T Bar is 800mm. The Bar is 41mm U section and is supplied with a plastic capping strip to cover the underside of the arm and two end caps. The arm has an attachment plate in the centre with holes that can be used for mounting to 50mm or 25mm diameter pipe or bolting to posts or buildings.
The arm is supplied complete with two 50mm U bolts.
[Shown with Wind Vane, Anemometer and Solar Shield.]
Base Mounting Plate
The Base Mounting Plate is used to facilitate the attachment of Wind Vanes, Anemometers and Solar Radiation Sensors to posts or buildings. Two countersunk holes in the centre of the plate are used to attach the base. The two outer holes are then used to attach the base to a post or building.
The outer holes are 5mm in diameter and 55mm apart. There is a groove in the plate to allow the cable, from the centre of the base, to emerge at the side of the Base Mounting Plate.