The wind speed sensor is a wide range of wind speed (air flow rate) transmitters for monitoring, control and wind speed regulation and ventilation systems.
Features:
· Convert air flow rate to 4-20mA or a 0-10V signal
·Linear signal output
· Made of adjustable resistance material
·All electronic instrument reading air flow rate
·AC or DC power supply
·With temperature compensation
·Sleeve sensor for installation
·0-10V temperature output signal
·Fuse protection Application: ESF—35—2 air flow converter has a wide range of applications
·Measure air flow rate via PLC/remote site/EMS
·Adjust air flow rate ·Monitor air flow rate
Two prohibitions:
1. It is forbidden to use a wind speed sensor in flammable gas environment.
2. It is prohibited to place the wind speed sensor probe in flammable gas.
Seven don’t:
1. Do not disassemble or modify the wind speed sensor;
2. Do not expose the probe and the anemometer body to the rain;
3. Do not touch the internal sensor part of the probe;
4. Do not place the anemometer in a place with high temperature, high humidity, dust and direct sunlight;
5. Do not wipe the wind speed sensor with a volatile liquid.
6. Do not drop or press the wind speed sensor;
7. Stay away from the sensor part of the probe while the anemometer is energized.
Three MUST: Be sure to use the wind speed sensor correctly according to the requirements of the instruction manual; in use, if the wind speed sensor emits an abnormal smell, sound or smoke, or if liquid flows into the anemometer, be sure to turn off the battery immediately; the wind speed sensor is long-term. Always remove the internal battery when not in use.
1. The wind direction sensor is removed from the package and assembled. The point of attention is: the wind mark rod is inserted in the direction of the arrow; the front and rear weights of the wind direction indicator should be adjusted, and the front and rear wings should be in the same plane as the rotation axis; the north pole and the north line should be In the same direction.
2. The sensor component is composed of a wind speed sensor, a wind direction sensor and a sensor bracket. When assembling, the sensors should be connected to the respective inserts, then sat on the bracket sleeve, and tighten the screws.
3. The working voltage of the sensor is usually 5 VDC. Owing to the built-in lightning protection device, the actual working voltage should not exceed 6 volts.
Wind speed sensor (pulse type), 1.5 pulses = 1 m / s, the number of pulses measured per second is equal to 1 m / s for wind speed.
When the number of pulses measured per second is 3, it is equal to 2 m/s. analogy.
Mine oxygen sensor alarm value is 19%, the mine carbon dioxide alarm value is 2000ppm. Oxygen sensors are a critical component in engines that use three-way catalytic converters to reduce exhaust pollution. Since the air-fuel ratio of the mixture differs by the theoretical air-fuel ratio, the purification ability of the three-way catalyst for CO, HC and NOx will drop sharply. Therefore, an oxygen sensor is installed in the exhaust pipe to detect the concentration of oxygen in the exhaust gas, and The ECU sends a feedback signal, and then the ECU controls the increase and decrease of the fuel injection amount of the injector to control the air-fuel ratio of the mixture to be near the theoretical value.
The gas sensor T1 is mounted on the roadway which is no more than 5 m from the heading. The methane sensor T2 is installed within the range of 10-15m of the return air inlet. The methane sensor must be suspended vertically above the roadway, no more than 300mm from the top plate, and not less than 200mm from the roadway. T1 alarm concentration is 0.8%CH4, power-off concentration≥0.8%CH4, re-concentration concentration<0.8%CH4, T2 alarm concentration≥0.8%CH4, power-off concentration≥0.8%CH4, re-concentration concentration<0.8%CH4
1, wind speed measurement (single hole)
2. Wind speed average mode
3. Air flow measurement (CMM/CFM)
4, air flow average mode
5, data retention (wind speed / air flow)
6, maximum / minimum / average (wind speed / air flow)
7, automatic shutdown
8, circuit: the use of high-speed integrated MCU
9, display: LCD dual display, 4-digit display
10. Sample: sample once every 1 second
11, sensor: wind speed sensor using ultra-low friction bearings
12, temperature sensor: NTC type high precision thermistor
13. Automatic power off: In order to extend battery life, the meter will automatically turn off after 20 minutes.
14, operating temperature: 32 ° F ~ 122 ° F (0 ° C ~ 50 ° C)
15, storage temperature: 14 ~ 140 ° F (-10 ~ 60 ° C)
16, operating humidity: <80% RH
17, storage humidity: <80% RH
18, operating height: the maximum is 2000 meters (7000 feet)
19, battery model: 9V (Model: NEDA 1604)
20, battery life: about 80 hours (such as the backlight continues to work, battery life will be shortened)
21, battery capacity: about 8.3 mA DC
22. Weight: 725g (including battery and fan)
23. Size: Anemometer: 178×74×33mm, wind fan: 70mm (diameter)
Determination of wind speed Commonly used instruments are cup anemometer, wing anemometer, catastat thermometer and hot bulb anemometer. The wing and cup anemometers are easy to use, but have a high inertia and mechanical friction resistance and are only suitable for measuring large wind speeds.
Hot ball electric anemometer
1. Construction principle It is an instrument capable of measuring low wind speed, and its measurement range is 0.05-10m/s. It consists of two parts: a hot ball type probe and a measuring instrument. The probe has a glass ball of 0.6 mm in diameter surrounded by a nickel-chromium wire loop for heating the glass ball and two thermocouples connected in series. The cold end of the thermocouple is attached to the phosphor bronze pillar and is directly exposed to the gas stream. When a certain amount of current passes through the heating coil, the temperature of the glass ball rises. The degree of elevation is related to the wind speed, and the degree of increase in wind speed is large; on the contrary, the degree of elevation is small. The degree of elevation is indicated on the meter by a thermocouple. According to the reading of the meter, check the calibration curve to find out the wind speed (m/s). 2. How to use
1 Before using, observe whether the pointer of the meter points to zero. If there is any offset, you can gently adjust the mechanical adjustment screw of the meter to return the pointer to zero point;
2 Place the calibration switch in the off position;
3 Insert the measuring rod plug into the socket, the measuring rod is placed vertically upwards, the screw plug is pressed tightly to seal the probe, the “correction switch” is placed at the full position, and the “full adjustment” knob is slowly adjusted to make the meter pointer Full position
4 Put the “correction switch” in “zero position”, and slowly adjust the “coarse adjustment” and “fine adjustment” two knobs to make the meter pointer point at the zero point;
5 After the above steps, gently pull the screw plug to expose the probe (the length can be selected as needed), and make the red dot on the probe face the wind direction. According to the meter reading, check the calibration curve. The measured wind speed;
6 After measuring a few points (about 10 minutes), the above steps 3 and 4 must be repeated to standardize the current in the meter; 7 After the measurement, the “correction switch” should be placed in the off position. 3. Precautions
1 This instrument is a relatively precise instrument, which is strictly resistant to collision vibration and should not be used in places with excessive dust or corrosiveness.
2 The instrument is equipped with 4 batteries, which are divided into two groups and are connected in series, and one group is single-section. When adjusting the “Full Degree Adjustment” knob, if the meter cannot reach full scale, it means that the single battery has been exhausted; when adjusting the “coarse adjustment” and “fine adjustment” knob, if the meter pointer cannot return to zero, the explanation The three batteries have been exhausted; when replacing the battery, open the small door at the bottom of the instrument and connect it in the correct direction.
3 After the instrument is repaired, it must be recalibrated.
1. Measure the speed and direction of the average flow.2. The pulsation velocity of the incoming stream and its spectrum are measured.
3. The Reynolds stress in the turbulent flow and the velocity dependence and time dependence of the two points are measured.
4. The wall shear stress is measured (usually using a hot film probe placed flush with the wall, the principle is similar to hot wire speed measurement).
5. The fluid temperature is measured (the probe resistance is measured in advance with the temperature of the fluid, and then the temperature is determined based on the measured probe resistance.
1. The thermal anemometer is a meter used to measure the airflow speed. It is widely used because of its high measurement accuracy, ease of use, wide measuring range and high sensitivity. The thermal anemometer uses the calorimetric principle to measure the wind speed, and is mainly composed of a wind speed probe and a measuring indicating instrument. As the structure has a hot ball type and a hot line type, the display form has various types such as pointer type and digital type, but there are only two types according to the working principle, that is, constant current type and constant temperature type. The constant current type is a constant current for the wind speed sensitive component. After heating to a certain temperature, the degree of cooling with the change of the air flow is a function of the wind speed. The constant te
mperature type is adjustable for the current of the wind speed sensitive component. The operating temperature of the wind sp
eed sensitive component in different thermal equilibrium states is basically inconvenient at different wind speeds, that is, the resistance value is substantially constant, and the power consumed by the sensitive component is a function of the wind speed.
2. Working principle of constant current anemometer: The wind speed probe is a sensitive component. When a constant current passes through its heating coil, the temperature inside the sensitive component rises and reaches a certain value in the still air. At this time, the thermocouple of the measuring component therein generates a corresponding thermoelectric potential, and is transmitted to the measurement indicating system, and the thermoelectric potential and the reference back electromotive force generated in the circuit cancel each other out, so that the output signal is zero, and the meter pointer can also refer to Zero or zero value. If the heat sensitive component at the end of the wind speed probe is exposed to the external air flow, due to the heat exchange, the thermocouple thermoelectric potential will be changed at this time, and compared with the reference back electromotive force, a weak difference signal is generated, which is measured by the measuring instrument. The system amplifies and pushes the meter pointer change to indicate the current wind speed or the current wind speed value through the display after being processed by the microcontroller.
3. The constant temperature anemometer uses a feedback circuit to keep the temperature and resistance of the wind speed sensitive component constant. When the wind speed changes, the temperature of the heat sensitive component changes, and the resistance also changes, causing the voltage across the heat sensitive component to change. At this time, the feedback circuit plays a role, causing the current flowing through the heat sensitive component to change accordingly, and the system Restore balance. The above process occurs instantaneously, so the increase in speed is like an increase in the output voltage of the bridge, and the decrease in speed is also equal to the decrease in the output voltage of the bridge.
4. Three cups of eddy current sensor: The rotating shaft of the wind cup is a metal toothed turntable, and the induction head is composed of a
coil. The coil is connected to a high-frequency alternating current, and an alternating magnetic flux is generated around the coil. The metal tooth forms a closed circuit, and the metal tooth generates an eddy current. The metal tooth generates an alternating magnetic flux in addition to the heat dissipation, resulting in an alternating magnetic flux in the opposite direction. The inductance of the coil is reduced and a change in impedance is caused. When the rotating shaft rotates, a change of the magnetic flux of the coil is caused to output a continuous pulse signal, and the pulse signal is counted to calculate the rotational speed of the rotating shaft.
5. Three cups of optocoupler sensor type sensor
, when the wind cup rotates, the multi-tooth turntable is rotated by the main shaft, so that the lower photo transistor receives the light irradiated by the upper LED, and is turned on or off, forming a speed with the cup. The proportional frequency signal is counted by the counter and converted to the actual wind speed value.
DIY simple wind direction meter measures the wind direction:
The sensor is a mechanical rotary sensor that senses the flow of air at a distance of 11m from the ground, detects and photoelectrically converts the speed and direction of air flow, and performs digital quantization, time averaging, storage, etc., and then transmits it to the communication device and route through the system. Indoor meteorological observation workstation.
The indoor data processing workstation (DPU) calculates and produces a 2-minute average wind speed and wind direction report, based on the wind data of the sensor for 5 seconds, generates reports of gusts and uncertain wind directions, and performs vector wind decomposition corresponding to the direction of the runway and the direction of the sag.
Measuring range: Air speed: 0.5 ~ 3M / sec; 0.5 ~ 40M / sec
× 175 (H) × 135 (D) mm
2. The pulsation velocity of the incoming stream and its spectrum are measured.
Wind Sensor 