Current sensors

Apart from such important measurable values ​​as voltage, power or current impedance, it is necessary to define the current parameters to describe the phenomena occurring in electrical circuits. These parameters are tested by professional current sensors available in this category. Modern measuring technology enables precise and fast measurement of both direct current and alternating current with regular and irregular waveforms. For this purpose, measuring instruments have been designed which, based on magnetic circuits and semiconductor elements, allow to obtain information about the value of the current flowing in the tested circuit.

The Botland store proposes to buy meters and current flow sensors, which will be ideal elements for building a comprehensive measurement system. They can also come in handy for many other projects!

What is the current sensor? How do electric current sensors work?

Current sensors are commonly used devices. Depending on the type of device, they can act as independent measuring devices or modules that can be added to a given electronic project. In this category you will find many types of current sensors. Devices such as - for example - Grove ACS70331 DC current sensor enable precise measurement of DC / AC � 5 A (direct current and alternating current). The construction of the sensor is based on the giant magnetoresistive (GMR) technology. The sensor measures the current with a basic sensitivity of 200 mV / A. The module is compatible with Arduino and Raspberry Pi. This sensor, as well as many others available in our Botland store, is also used to detect a magnetic field. It uses an integrated, low-resistance primary wire through which the current flows. The modules are compatible with controllers such as Arduino and Raspberry Pi, but they can also work with other parts of programmable electronics.

How to measure electric current?

Before taking any measurement, please read the instructions carefully. When you want to measure the current in an electric circuit, be sure to carefully follow the safety rules to avoid electric shock and damage to the circuit components.

First of all, you must not touch non-insulated circuit elements as they may be live (wrong connection). Secondly, the principle of limited trust towards bystanders and animals should be applied to prevent their unauthorized contact with live parts. If you want to measure the current intensity, disconnect the circuit from the supply voltage and, in the case of circuits with capacitors, wait a few minutes after turning it off to discharge them. Remember to obey all of the specific steps that can be easily found in the manufacturer’s manual.

When connecting the ammeter directly to the circuit, it is necessary to determine for which element you want to measure the current intensity. Then, the measuring system should be connected in series with this element. If the current flowing in the circuit exceeds the allowable measurement range, a voltage divider, inductive current transformer or semiconductor sensor should be then connected. The obtained measurement data can be sent to the analog input in the Arduino or Raspberry Pi electronics. Thanks to this you can implement, for example, overcurrent protection that controls the relay, or a measurement system that monitors electricity consumption.

Current sensors and Hall effect

Some more advanced sensors measure the current using the so-called Hall effect. An excellent example are the sensor modules manufactured by Pololu. With these devices you can monitor the power consumption of receivers and detect the load connected to the network. It is also possible to implement short-circuit and overload protection.

In the case of Pololu sensor modules, the analog output enables the sensor to be connected to the Arduino. Thanks to this, it is possible to read the voltages representing the current in the tested circuit in a very convenient way. Full compatibility with Arduino and other programmable electronics is an advantage for many other reasons as well. If, on the other hand, you want to measure alternating current in many places of the circuit, then a good solution is to use the SCT 013-030 sensor, which allows you to measure sinusoidal alternating current with RMS value up to 30A, without disconnecting the tested circuit.