Installation of wind sensor

Installation of wind sensor

Ⅰ.Selection of instrument installation position

Ⅱ.Overview and working principle

The wind direction and wind speed sensor is used to measure the speed and direction value of the ground wind 10 meters away from the ground, and convert it into electrical signal, which can be directly transmitted to the display instrument or recording equipment for processing.

The sensor consists of wind direction sensor, wind speed sensor and sensor bracket. The power supply of the sensor is + 12V.

⒈Wind direction EL15-2/2D is a photoelectric wind direction sensor with low starting wind speed. The wind direction signal generating device is composed of a 6-8 digit Gray code optical disc driven by the weathercock rotating shaft connected to the weathercock. The code disc is composed of seven equally-divided concentric circles with 0, 2, and 2 from the inside to the outside. 22, 23, 24, 25, (26, 27) are equally divided, and each adjacent part is treated with light transmission and opacity, and the corresponding 6 to 8 pairs of photoelectric coupling devices located on the same radius on both sides of the code wheel are outputted. Up to 8-bit Gray code, a set of (6-8) infrared light-emitting diodes are installed on the top of the code disc, and a set of photoelectric converters (6-8) are installed below the code disc, all facing the (7) tracks of the code disc. With the rotation of the wind vane, the photoelectric tube under the code disc receives a change in the code. Each gray code represents a wind direction with a resolution of 5.6 to 1.4 degrees. Only one bit can be changed at a time, this encoding method helps to eliminate garbled codes. The sensor has three output modes: Gray code, voltage and current.

The heating element inside the sensor keeps the entire bearing from freezing in cold weather. It can generally provide 25W heating power. It is recommended to install a thermal switch at the sensor bracket to start the heating device when the temperature is lower than 4℃.

⒉The wind speed EL15-1/1A is an optoelectronic anemometer with fast response and low starting wind speed. The sensing part is composed of three light-weight conical wind cups, which can provide good linearity throughout the working range until the wind speed reaches 60m/s. The cutting disc attached to the central stainless steel shaft rotates with the shaft, and cuts the infrared beam 14 times for each revolution, thereby generating a pulse chain from the photoelectric crystal. The output pulse rate is proportional to the wind speed. However, for the best accuracy, the characteristic transmission equation should be used to compensate for starting inertia and slight overspeed.

Ⅲ. Installation of wind sensor

Installation of automatic station wind-standard

1. The wind direction and speed sensor of the automatic station is installed on the wind pole on the east side of the observation field.

2. Operation test should be carried out before installation, and installation can be carried out only when the operation is normal. 

3. The sensor should be installed on a firm wind pole, and the connecting pole of the wind direction sensor and the wind speed sensor should be aligned in the north-south or east-west direction. It is also equipped with lightning protection device.

4. The wind speed sensor (the center of the wind cup) is 10-12 meters above the ground. The north sign of the wind direction sensor should face north.

5. The axis of the sensor should be perpendicular to the horizontal plane. /6. The connecting cable of the wind direction and wind speed sensor is connected to the collector through the cross arm, and the cable connected and out of the cross arm is directly inserted through the inlet of the first wind pole. Then go down the wind pole and extend to the ground.

7. The connection (red copper wire) of the lightning rod goes down the pole and connects firmly with the ground wire. The ground wire is buried in the soil under the wind pole, and the ground resistance should not be greater than 5 ohms. The lightning protection wire shall be tied on the wind pole once every 1 meter to prevent the lightning protection wire from swinging in the air.

8. Generally, wind measuring instruments should be used in an open area, with a ground height of 10m-12m. The distance between the wind measuring instrument and the obstacle is at least more than 10 times the height of the obstacle; or 6~10 meters higher than the obstacle; or installed in the center of the flat roof, do not move to the side to avoid inclination in a certain direction .

9. For the sake of safety, first remove the sensor when installing, then install the cross arm on the wind rod, then install the sensor on the corresponding position of the cross arm, and tighten the screws.