What is ELECTRIC CURRENT SENSORS for your purpose? | Infineon Technologies Technical Column

ELECTRIC CURRENT SENSORS are used to measure the current flowing through electronic circuits. Current sensors also operate a variety of motor-based machines found in homes, workplaces, transportation, and even medical facilities, and they also help prevent machines from being damaged by excessive ELECTRIC CURRENT SENSORS current.
It is important to keep in mind that the way ELECTRIC CURRENT SENSORS are used varies depending not only on the type of machine but also on how you want it to operate. If you do this incorrectly, the sensor may not function properly, so you need to be careful. For example, problems can arise when the magnitude of the electricity being measured is different.
Currents vary widely, from as little as 1 milliampere to several thousand amperes. The appropriate ELECTRIC CURRENT SENSORS also varies depending on the connection method, such as direct current or alternating current. It is important to understand these differences and use the optimal ELECTRIC CURRENT SENSORS for your purpose.
So, what kinds of ELECTRIC CURRENT SENSORS are there? Let's explore together. The first thing you need to know is the types of ELECTRIC CURRENT SENSORS. There are three main types:

1. Resistance detection type
2. Core-type magnetic field detection type
3. Coreless magnetic field detection type

The difference lies in the detection method, which we will explain in more detail next.

There are three types of ELECTRIC CURRENT SENSORS, and each type has a different detection method.
Each has different characteristics, so be sure to understand them before using them.

1. Resistance detection type
This is a method of detecting current using RESISTORS called a shunt resistor.
When detecting current, the current value is measured by the difference in voltage drop across the shunt resistor connected in series.
The typical measurement range is 0A to ±50A.

2. Core-type magnetic field detection type
This method detects the current value based on the strength of the magnetic field captured by the core (donut-shaped magnetic material) inside the sensor.
The core surrounds the current conductor and measures the magnitude of the current by detecting changes in the magnetic field emitted from the current conductor.
The typical measurement range is 0A to ±2000A.

3. Coreless magnetic field detection type
This method measures the voltage using a part called a Hall element inside ELECTRIC CURRENT SENSORS 's IC, and detects the magnitude of the current from that voltage.
This is also called a coreless method, and instead of using a core, it uses a Hall element. The Hall element senses the magnetic field and generates a voltage, which then detects the current.
The typical measurement range is 0A to ±50A.

As explained in points 1 to 3, the amount of current that can be handled varies depending on the detection method. However, the measurable range also varies depending on the product specifications, usage environment, conditions, etc., so be sure to check the specifications and data sheet.
Furthermore, magnetic field detection types differ in their orientation within the detection circuit depending on whether they have a core or not (types 2 and 3 above). This point will be explained in more detail in the next section.

There are three types of ELECTRIC CURRENT SENSORS, and each type has a different detection method.
Each has different characteristics, so be sure to understand them before using them.
As mentioned above, magnetic ELECTRIC CURRENT SENSORS are suited to different applications depending on the object being measured. We will now explain in more detail the measurement characteristics of each sensor.
One of the disadvantages is cost. Because IPDs are semiconductors, they tend to be more expensive than mechanical relays and mechanical FUSES, which are not semiconductors. However, there are probably not many cases where all of the functions of an IPD are required. Costs can be reduced by selecting only the necessary functions and narrowing down to IPDs that have those functions. Additionally, creating reusable blocks during the design stage can ultimately reduce costs.
Next is the design man-hours. Compared to the mechanical components mentioned above, the design man-hours can be greater. This is because IPDs have complex internal structures, and although the basic function is switching, additional functions are incorporated, so the design and integration of these functions takes man-hours.
Additionally, evaluation tests are required to ensure that each block functions correctly. This means there is a lot to do, which can result in a lot of work overall. However, the more effort you put in, the more advanced functionality you can ensure, which in turn increases reliability. As a result, it can be said that this is not a major disadvantage.
Finally, we will talk about the risk of loss of control. Although the protection function works against overcurrent, it does not work against the rated current. Therefore, depending on the circuit on the output side of the IPD, there is a risk of loss of control. However, there is a way to reduce this risk. This is by using a circuit called an active clamp.
An active clamp is a circuit that absorbs the "reverse electrical force" that occurs when the switch is turned off and redirects it in the correct direction, preventing damage to SWITCHES. This function reduces the risk of SWITCHES operating in an unexpected manner.
There are some disadvantages to IPD, but please understand that there are ways to deal with all of them, so they are not particularly big problems.

When selecting ELECTRIC CURRENT SENSORS, keep the following four points in mind:

Point 1. What is the current range you want to measure?
All ELECTRIC CURRENT SENSORS have a set measurement range. For example, if you want to measure a current of 1A, you need to choose ELECTRIC CURRENT SENSORS that covers that range. You can check the sensor's measurable range in its specifications or data sheet.

Point 2. What level of measurement accuracy do you require?
The higher the measurement accuracy, the more reliable the results will be. For this reason, you may be tempted to choose a high-accuracy instrument. However, higher accuracy also tends to mean higher prices. It is important to determine in advance the level of accuracy you are willing to accept.

Point 3. Does the size and shape suit the project?
ELECTRIC CURRENT SENSORS vary in size and shape depending on the type. If they are too large, more space will be required for installation, and you may need to redesign your system. Conversely, if they are too small, handling, including installation, may become difficult, so it is important to select a sensor with the appropriate size and shape.

Point 4: What is your budget?
Even for the same type of ELECTRIC CURRENT SENSORS, prices vary depending on the specifications, manufacturer, material, etc. Start by researching the market price. Sensors that are too cheap can raise concerns about accuracy and durability, so setting a budget based on the market price will help you avoid making the wrong sensor selection.

We recommend that you keep these points in mind when comparing various options.

When selecting ELECTRIC CURRENT SENSORS, keep the following four points in mind:
ELECTRIC CURRENT SENSORS is a device used to measure the amount of current flowing through an electronic circuit. However, current that is too large can damage machinery. Current that is too small can also prevent circuits from functioning properly. ELECTRIC CURRENT SENSORS play a role in preventing such electrical problems.
However, as explained above, there are various advantages and disadvantages depending on the type of ELECTRIC CURRENT SENSORS. Choosing one without knowing these can cause problems. Keep these four points in mind when selecting ELECTRIC CURRENT SENSORS that suits your purpose.

NEXTY Electronics offers reliable and detailed guidance on search methods and product advice to those who are having trouble choosing a product. If you are worried about not knowing which product to choose, please feel free Inquiry using the form.