What are the important factors that affect the selection of terminal wires?

At present, the use of switch power supply terminal blocks in electronic products has become a development trend, and the components of switch power supply terminal blocks themselves are gradually expanding, and they can bear greater output power. With the increase in the volume of wiring terminals, their necessity in the role of machinery and equipment has become increasingly prominent, and they have also played an increasingly critical role in ensuring the characteristics of the product. Below are the key elements for selecting hazardous wiring terminals.

1、 Output power solution elements

One of the first factors that must be considered is the output power of the components. There is no unified standard for determining the output power and characteristic specifications of the wiring terminal products. The specifications and models of terminal products manufactured in Europe use IEC standards, while those manufactured in the United States use UL specifications.

The difference between these two standards is significant. Technical engineers who are not familiar with the product model determination method may take great risks, as the components used may not meet the necessary output power level, or the specifications and models of the components used may far exceed the requirements of the design scheme. In Europe, the rated current of components is determined based on the temperature of the metal material conductor when the detected current increases. When the temperature of the metal material pin is higher than the working temperature by 45 ℃, the precise measurement staff will use the current at this time as the rated voltage value (or higher current) of the component. Another item of the IEC specification model is the allowable current, which is 80% of the larger current amount. Unlike this, UL standards will use 90% of the current allowed for components when the temperature of the metal material conductor is higher than the operating temperature by 30 ℃. It is not difficult to see that the temperature of a part of the metal material conductor is a crucial factor in all applications. This is crucial for mechanical equipment. Due to the fact that mechanical equipment generally needs to work in an environment where the temperature reaches 80 ℃. If the temperature of the terminal block is 30 ℃ or 45 ℃ higher than this temperature, then the temperature of the terminal block may exceed 100 ℃. Based on the type of tolerance value and insulation layer material selected for the selected components, the product must operate at a current less than the rated current to ensure reliable operation within the expected temperature range. Sometimes, the raw materials suitable for compact packaged components may not have sufficient consideration for heat dissipation regulations, so the current required for the application of such terminal components must be significantly lower than the rated current.

Another factor often overlooked when selecting components is the terminal connection technology used in the product. Most switch power supply terminal products still use buried hole interface method. This type of method can present the necessary mechanical equipment and ensure reliable electrical contact with the power layer embedded in the double-layer circuit board. There are various types of pins used to connect terminal blocks to circuit boards. Some companies only present single leg model specifications, while others present multi leg products. The advantages of multi legged products depend on: it can distribute the current more evenly throughout the wiring of the circuit board, demonstrate more reliable mechanical equipment, and improve the robustness of welding.