Resistors for LEDs: calculator for correct resistance calculation

Nowadays, LEDs are used in almost all areas of human activity. But, despite this, for most ordinary consumers it is completely unclear, thanks to what and what laws apply at work of light-emitting diodes. If such a person wants to arrange lighting with such devices, then many questions and finding solutions to problems are inevitable. And the main question will be - "What kind of thing is this - resistors, and why LEDs need them?»

What is a resistor and its purpose?

A resistor is one of the components of an electrical network, characterized by its passivity and at best, differs in the resistance of the electric current. That is, Ohm's law must be valid for such a device at any time.

The main purpose of the devices is the ability to vigorously resist electric current. Due to this quality, resistors are widely used in the need for artificial lighting, including the use of LEDs.

Why is it necessary to use resistors in the case of LED lighting?

Most consumers know, that an ordinary incandescent light bulb gives light when directly connected to any power supply. The light bulb can work for a long time and burns out only then, when the incandescent filament is excessively heated due to too high a voltage. In this case, the light bulb, in some way, implements the function of a resistor, because it is difficult to pass electricity through it, but the higher the voltage, the easier the current is able to overcome the resistance of the bulb. Of course, put in one row such a complex semiconductor part, both LED and ordinary incandescent light bulb are possible.

It is important to know, that an LED is such an electrical device, for the operation of which it is better not the current itself, and voltage, that is online. Example, if such a device is selected voltage 1,8 V, and comes to him 2, then, most likely, it will burn out - if you do not reduce the voltage to the desired level adjustment in time. That's why you need a resistor, which stabilizes the power supply, so that the voltage applied to them did not disable the device.

This is extremely important:

• to be determined, what type of resistor is required;
• determine the need to use an individual resistor for a specific device, what the calculation is for;
• consider the type of light source connection;
• планована кількість світлодіодів в освітлювальної системи.

Wiring diagrams

With a sequential arrangement of LEDs, when they are arranged one behind the other, usually one resistor is enough, if you can correctly calculate its resistance. This is due to the fact, that the electrical circuit has the same current, in each place of installation of electric devices.

But in the case of a parallel connection, each LED has its own resistor. If you ignore this requirement, then all the tension will have to pull one, the so-called "limiting" LED, that is, who need the least voltage. It will fail very quickly, the voltage will be applied to the next circuit of the device, which will just as suddenly burn out. Such a turn of events is unacceptable, so, in the case of parallel connection of any number of LEDs requires the use of the same number of resistors, the characteristics of which are selected by calculation.

Calculation of resistors for LEDs

With a proper understanding of the physics of the process, calculating the resistance and power of these devices can not be called an impossible task, with which the average person can not cope. To calculate the required resistance of resistors, The following points must be taken into account:

• special marking, present on devices, usually shows unnecessary supply voltage, and voltage, selected LED for your work, that is, the voltage drop. This numerical value is used to calculate the minimum required voltage or to select power resistors;
• the numerical value of the voltage across the resistor is defined as the difference between the supply voltage of the LED and the voltage of the unit;
• magnitude, flowing through an electric current resistor, is obtained by dividing the residual voltage on the device by the value of its resistance;
• to calculate the required resistance, the residual voltage should be divided by the amount of current required for the smooth operation of the system.

Calculation of resistors using a special calculator

Usually, calculation of the resistance of such devices, required for any LED, is carried out with the help of calculators specially designed for this purpose. Such calculators, convenient and highly efficient, no need to download and install from somewhere - you can calculate the resistor online.

Resistor calculation calculator allows you to determine with high accuracy the required power and resistance of the resistor, which is installed in the LED circuit.

To calculate the required resistance, you must enter in the appropriate lines of the online calculator:

• LED supply voltage;
• rated voltage of the LED;
• rated current.

Further, you need to select the connection scheme used, as well as the required number of LEDs.

After pressing the corresponding button, the calculation is performed and the received calculation data is displayed on the monitor screen., with the help of which it is possible to organize artificial LED lighting in the future without much effort.

There is also some base in online calculators, containing data on LEDs and their parameters. The possibility of calculation is presented:

• nominal value of the device;
• color marking;
• current consumed by the circuit;
• dissipated power.

Man, not very well versed in electricity and physics, in most cases will not be able to calculate the devices for LEDs. For this reason, making calculations with the help of a functional and convenient online calculator is an invaluable help for ordinary people, who do not have the method of calculations using physical formulas.

Most well-known manufacturers of LEDs and strips based on them, they also publish their own online calculator on their official websites, with which you can not only choose the right resistors and LEDs, but also to calculate the parameters of current devices used in different operating modes at variable current values, temperature, applied voltage, etc.