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The assembly of THT components

In this section, we will discuss different types of THT components – their use, and some practical advice regarding the assembly and soldering of threaded components.

Types of THT components and their use

THT components can be grouped into different types such as resistors, capacitors, diodes, transistors, or integrated circuits. Depending on the future use and characteristics of a project the methods and possibilities of assembly may differ. Here are short descriptions of the aforementioned components:

    • Resistors are used to regulate the electricity and voltage in electronic circuits.
    • Capacitors are used to accumulate energy and filter the signals.
    • Diodes let the electricity flow only in one direction and may be used e.g. in rectifiers.
    • Transistors function as amplifiers or switches in electronic circuits.
    • Integrated circuits consist of a lot of components placed on a silicon base.

Assembly of THT components – practical advice

THT assembly is done by placing threaded components in appropriate holes on the PCBs. To make THT assembly run smoothly it is important to follow a few practical rules:

    1. Before starting the assembly check if the components are appropriate for the certain project and are undamaged
    2. Place the components following the marks on the PCB paying attention to the polarization in the case of diodes or electrolytic capacitors.
    3. Hold the components during assembly to prevent them from falling during soldering. You may use tape for this.
    4. Cut the extensive leads of the components after soldering to prevent short circuits.
Soldering threaded components: methods and tools

Soldering threaded components: methods and tools

Soldering is the key stage of THT assembly ensuring long-lasting mechanical and electric connections. Proper soldering of threaded components requires the use of accurate techniques and tools:

    • The THT soldering process requires the use of a soldering iron of appropriate power and good quality solder made from, e.g.: tin with or without admixture of lead.
    • Before soldering clean the leads of components and soldering spots on the PCB to ensure better adhering of the solder
    • Heat the lead of the component and the path on the PCB at the same time, next place the solder to achieve a long-lasting and flexible connection.
    • Avoid overheating of components and using too much solder as this may lead to damage and short circuits.

THT assembly can be performed both manually and automatically. In the case of automatic methods, a variety of soldering techniques may be used – one of which is “a wave” of the binder. This process consists of automatic soldering using a wave of solder. Alternatively, automatic selective waves may be used. In this case, special nozzles enable accurate point soldering of the leads of components which increases the precision and the effectiveness of the whole assembly process.

Nordes EMS consistently focuses on the precision of selective soldering in the production of contract electronics. ERSA VERSAFLOW 4/55 purchased by Nordes is an advanced machine for selective soldering, which gained its appreciation for various reasons:

– Ensures precision and control: the automatic machine enables precise and controlled soldering, resulting in high quality joints;
– Material savings: the selective soldering process allows efficient use of solder, which in turn contributes to material savings;
– Precise solder dosage: The ERSA VERSAFLOW 4/55 enables precise, reproducible and accurate dispensing of solder to the designated assembly points, which is important for high-precision assembly, especially in high-volume production;
– High productivity: the machine has a high throughput, which speeds up the contract electronics manufacturing process;
– Error elimination: the automatic process eliminates errors, increasing the reliability of the soldered joints.

The purchasing of the machine ERSA VERSAFLOW 4/55 is proof of Nordes’s engagement in the development of the complexity of offered services. That enables Nordes to offer the highest quality of electronic solutions to its customers. The machine is equipped with an advanced system of temperature and stability control which enables precise monitoring and adjusting the temperature in real time which positively affects the soldering conditions for a variety of electronic components. In that Nordes can provide the highest quality of solder connections in the production of electronics.

By applying the advice above it is possible to conduct the assembly of THT components safely and effectively as well as solder the components ensuring that the quality and connections are solid and reliable.


THT assembly and PCBs

In this section of the article, we will look closely at the relations between THT assembly and PCBs. We will also investigate the production process of PCBs and the method of assembling THT components on the PCB.


Production of PCBs: the process and rules

The Production of PCBs is a process that consists of designing, manufacturing, and assembling elements on printed circuit boards. The process is made of a few stages such as designing the electrical diagram, designing the layout of the PCB, manufacturing the PCB, and the assembly of elements. In the case of assembling components that require the use of the THT method it is mandatory to take into consideration the specifics of this method while designing the PCB.

During the process of assembling THT components, the PCBs must have holes for the threaded components and must be designed with consideration of the requirements of this method of assembly. It must be remembered to keep the appropriate distance between the elements and to leave an appropriate amount of space for soldering.


THT assembly on the PCB: how it is made?

THT assembly consists of placing the threaded components in special holes on the PCB and next soldering their legs to the conductive paths on the PCB. For THT assembly there has been established a variety of tools and technique to ease the process. Examples of such tools and techniques are using a soldering iron as well as implementing various soldering techniques.

THT assembly offers solid and reliable electrical and mechanical connections which is of crucial importance in case of devices operating in tough conditions or needing high reliability. To achieve optimal conditions of THT assembly it is recommended to follow the rules and advice given in the previous sections of this article.


Differences between THT assembly on one and the other side of the PCB

Depending on the requirements of a project THT assembly can be conducted on one or the other side of the PCB. There are some differences between these two approaches that should be taken into consideration during the design and assembly of the PCB.


THT assembly on only one side of the PCB is simpler and faster because all the elements are soldered only on one side of the board. In the case of THT assembly on the other side of the board, the elements are assembled on one side of the board and soldered on the opposite side of the board which may require additional actions like turning the PCB or using special soldering techniques.

Comparing the advantages and disadvantages of both methods it can be stated that THT assembly on one side of the PCB is more suitable for easier projects where there is no need for safe space on the PCB. On the other hand, assembly on the other side of the PCB may be more useful in the case of more advanced projects where there is a need to optimize the space on the PCB and increase the density of components.