There are various typesMagnet and Hall sensorTo monitor AC or DC current, it is necessary to measure it in many applications in the industrial, automotive, or household fields. Below, Wei Kewei's editor will introduce itCurrent sensingHow manyMethod:

1DC inductionMagnet and Hall sensor：

DC induction depends on Ohm's law. By arranging parallel resistors with the system load, a voltage proportional to the system load current is generated on the parallel resistors. The voltage on the branch can be measured through differential amplifiers, such as current branch amplifiers, operational amplifiers, or differential amplifiers. It is usually used for load current< 100AThe situation.

2 Magnet and Hall sensorIndirect current sensing:

Indirect current sensing relies on Ampere's Law and Faraday's Law. By placing a circuit around a current carrying conductor, a voltage proportional to the current is induced on the circuit. This type of induction method is used for100A–1000ALoad current.

3 Low voltage side current induction:

It is a low input common mode voltage. The low voltage side current sensing connection is an inductive resistor between the load and the ground. This is desirable because the common mode voltage is close to ground, considering the use of a single power supply and rail to rail input/Output operational amplifier. The load is powered by a single power source and grounded through a resistor. The disadvantage of low voltage side induction is that it interferes with the ground potential of the system load and cannot detect load short circuits.

4High voltage side current induction:

The inductive resistance between the high side current sensing connection power supply and the load. High side induction is desirable because it directly monitors the current provided by the power supply, taking into account the identification of load short circuits. The test requires that the input common mode voltage range of the amplifier must have the characteristics of the load supply voltage. Afterwards, the output is measured through a current sensing device and the load is grounded.

5Current Transformer（CT）：

Current Transformer（CT）It is a transformer used to measure current.CTIt is a widely recognized sensor around high current solid-state energy meters today. It can measure extremely high currents with low power consumption. It is also very useful for measuring or monitoring high current, high voltage, and high-power circuits. They are used in various power systems, such as power supply, motor control, and lighting control.