One of the pillars on which many concepts in electronics are based is the concept of series and parallel connection of conductors. It is simply necessary to know the main differences between these types of connection. Without this, one cannot understand and read a single diagram.
Guidelines
Electric current moves along the conductor from the source to the consumer (load). Most often, a copper cable is selected as a conductor. This is due to the requirement that is placed on the conductor: it must easily release electrons.
Regardless of the connection method, the electric current moves from plus to minus. It is in this direction that the potential decreases. It is worth remembering that the wire through which the current flows also has resistance. But its value is very small. That is why they are neglected. Conductor resistance is assumed to be zero. In the event that the conductor has resistance, it is customary to call it a resistor.
Parallel connection
In this case, the elements included in the chain are interconnected by two nodes. They have no connections with other nodes. Sections of the chain with such a connection are called branches. The parallel connection diagram is shown in the figure below.
In a more understandable language, in this case, all the conductors are connected at one end in one node, and the other - in the second. This leads to the fact that the electric current is divided into all elements. This increases the conductivity of the entire circuit.
When connecting conductors to the circuit in this way, the voltage of each of them will be the same. But the current strength of the entire circuit will be determined as the sum of the currents flowing through all the elements. Taking into account Ohm's law, by simple mathematical calculations, an interesting pattern is obtained: the reciprocal of the total resistance of the entire circuit is defined as the sum of the reciprocals of the resistances of each individual element. Only elements connected in parallel are taken into account.
Serial connection
In this case, all elements of the chain are connected in such a way that they do not form a single node. This connection method has one significant drawback. It lies in the fact that if one of the conductors fails, all subsequent elements will not be able to work. A striking example of such a situation is an ordinary garland. If one of the bulbs in it burns out, then the whole garland stops working.
Serial connection of elements is different in that the current strength in all conductors is equal. As for the circuit voltage, it is equal tothe sum of the voltage of the individual elements.
In this scheme, the conductors are included in the circuit one by one. And this means that the resistance of the entire circuit will be the sum of the individual resistances characteristic of each element. That is, the total resistance of the circuit is equal to the sum of the resistances of all conductors. The same dependence can be derived mathematically using Ohm's law.
Mixed schemes
There are situations when on the same circuit you can see both serial and parallel connection of elements. In this case, we speak of a mixed connection. The calculation of such schemes is carried out separately for each group of conductors.
So, to determine the total resistance, it is necessary to add the resistance of elements connected in parallel and the resistance of elements connected in series. In this case, the serial connection is dominant. That is, it is calculated in the first place. And only after that the resistance of elements with parallel connection is determined.
Connecting LEDs
Knowing the basics of the two types of connecting elements in a circuit, you can understand the principle of creating circuits for various electrical appliances. Consider an example. The wiring diagram of the LEDs largely depends on the voltage of the current source.
With a low mains voltage (up to 5 V), the LEDs are connected in series. In this case, a pass-through capacitor and linearresistors. The conductivity of the LEDs is increased through the use of system modulators.
When the mains voltage is 12 V, both serial and parallel network connection can be used. In the case of serial connection, switching power supplies are used. If a circuit of three LEDs is assembled, then an amplifier can be dispensed with. But if the circuit will include more elements, then an amplifier is needed.
In the second case, that is, when connected in parallel, it is necessary to use two open resistors and an amplifier (with a capacity of more than 3 A). Moreover, the first resistor is installed before the amplifier, and the second - after.
With a high mains voltage (220 V), they resort to serial connection. At the same time, operational amplifiers and step-down power supplies are additionally used.
