Electrical basics: composition of circuits

Hello everyone, what I will talk about today is what novices need to know about circuits for the first time. If you are not a novice, please skip this content. Today I will talk about the composition of circuits.

Before talking about the composition of a circuit, first of all, the editor wants everyone to think about what a circuit is? …literally the path that electricity can take. In fact, this is the case, but this road also represents another meaning, that is, a loop. What electronic devices do you commonly use? If your guess is correct, it should be a mobile phone. Does charging the mobile phone require the charger to be connected to the power strip and then connected to the mobile phone to charge (of course you can also use a power bank). The mobile phone charging is a circuit, which includes the mobile phone, charger, and power strip.

As you can see from the above, circuits are connected and used by various devices. To sum up, a circuit is a whole composed of various components connected in a certain way. Such as a flashlight circuit.

flashlight circuit

From the picture above, we can know the composition of the circuit:

(1) Power supply. Its function is to convert other forms of energy into electrical energy, such as the dry battery shown in the picture above, which converts chemical energy into electrical energy. Another example is the power strip just mentioned. Inside the power strip is 220V mains power. As we all know, the mains electricity we use is obtained by wind power, hydropower, or by burning coal. Therefore, the electricity we use is also obtained by converting mechanical energy or chemical energy into electrical energy.

wind power

Thermal power generation

hydroelectric power

dry cell battery

(2) Load. The load is also called an electrical appliance, which is a device that converts electrical energy into other forms of energy. To be precise, it is a device that consumes electrical energy, such as the light bulb shown in the flashlight circuit or the mobile phone is the load when charging the mobile phone. Of course, there are many loads in life, such as rice cookers, induction cookers, computers, etc.

tungsten light bulb

rice cooker

(3) Control and protection devices. Its function is to connect or disconnect the circuit, so that the circuit or the circuit is protected from damage, etc., such as the switch shown in the flashlight circuit, or the air switch at home.

air switch

(4) Connect the wires. That is, it connects the power supply, load and protection control device. Its main function is to form a channel for transmitting electric energy, such as a data line.

Cellphone data line

Generally speaking, a circuit refers to the path through which current flows. It has two functions: one is to transmit and convert electrical energy, such as lighting circuits, motor circuits, and power transmission systems; the other is to transmit and process signals, such as television circuits, Computer circuits and various automatic control circuits, etc.

Summary: A circuit consists of a power supply, load, control and protection devices, and wires.