Hall effect sensor for current measurement
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HALL EFFECT SENSOR FOR CURRENT MEASUREMENT AIM: To measure output current based on the magnetic field using Hall Effect sensor Apparatus Required: 3144 hall effect sensor Capacitor 0.1 uf Resistor 10K Connecting wires Power supply Pin Configuration
Hall-effect sensor Specifications Digital Output Hall-effect sensor Operating voltage: 4.5V to 28V (typically 5V) Output Current: 25mA Can be used to detect both the poles of a magnet Output voltage is equal to operating voltage Operating temperature: -40°C to 85°C Turn on and Turn off time is 2uS each Inbuilt reverse polarity protection Suitable for Automotive and Industrial Applications Where to use hall-effect sensor A hall-effect sensor as the name suggests works with the principle of hall-effect and is used to detect magnets. Each side of the sensor can detect one particular pole. It can also be easily interfaced with a microcontroller since it works on transistor logic. So if you are looking for a sensor to detect magnet for measuring speed of a moving object or just to detect objects then this sensor might be the perfect choice for your project. How to use Hall-effect sensor There are two main types of hall-effect sensor, one which gives an analog output and the other which gives a digital output. A3144 is a digital output hall sensor, meaning if it detects a magnet the output will go low else the output will remain high. It is also mandatory to use a pull-up resistor as shown below to keep the output high when no magnet is detected. Applications Used to detect magnets(objects) in automation systems Used in magnetic door alarm system Measure speed in automobiles Detect the pole of magnets in BLDC motors Hall-effect sensors are commonly used for measuring the speed of rotating assemblies where a magnet on the assembly alternately makes and breaks magnetic contact with the sensor as the assembly rotates. They can also be used for applications such as determining when a door has been opened, position sensing and detecting the magnetic field created by current flow in a wire. The 3144 sensor can detect the basic presence of the magnetic field, but not the relative strength. The side of the sensor with the labeling is the side used for detection and detects the one pole of the magnet. The other side of the device will detect the other pole of the magnet. If the sensor does not seem to be detecting the magnet, try reversing it. Hall-effect sensors have several advantages over mechanic switches, chief among them are that by being solid-state, there is no concern about contacts wearing out and the switching speed can be quite high, as fast as 2uS. The main challenge with using Hall-effect sensors usually resides around the mounting of the sensor and any associated magnets. Power SupplyThe sensor can operate over a Vcc range of 4.5-24V. Digital OutputThe sensor output is open collector. A pull-up resistor of about 10K is normally used to pull the output high. This can be an external resistor or can be a built-in pull-up resistor on the MCU input. When a magnetic field is detected, the sensor pulls the output LOW. When the sensor output goes LOW, it can sink up to 25mA of current. . Download 50.67 Kb. Share with your friends:
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