Since its invention, terminal blocks have been widely used in various connection fields such as frequency converters and controllers. There is no specific parameter standard for the torque of screws during terminal installation and use, which requires users to determine according to specific situations.
The installation torque in wiring terminals is mainly reflected in plug-in wiring terminals with screw components and fence wiring terminals. The maximum locking torque will be found in the wiring terminal parameters. For example, in LC17-5.08, there are two options related to screws: maximum locking torque: 0.5-0.6Nm, and screw specification M3. The maximum locking torque is actually torque, which means that when using M3 specification screws, a force of 5-6 N needs to be applied at a distance of 0.1 meters from the terminal to lock the screw. Excessive force may cause slippage, while insufficient force may result in loosening during use.
In the UK series of terminal blocks, there are clear regulations on the torque requirements that the terminals must meet. The torque within this range will not damage the product and ensure its normal use. Taking UL-UK2.5B terminal blocks as an example, in the international terminal industry IEC60947-1 standard, it is specified that the copper parts of the product must meet a torque of 0.8N. Therefore, we can use this standard in the use of the product and adopt a torque of 0.8N to ensure low loss rate in practical application.
In addition to screws, the control of force in terminal blocks also includes the requirements for force when using plastic parts. The main function of the plastic part is to clamp onto the guide rail and fix the terminal itself. Due to the cold winter climate and decreased air humidity, the toughness of the product is lacking. Therefore, we should pay special attention to this aspect during use. We should slowly increase the pressure and stop applying force after hearing a "pop" sound to ensure the normal use of the product.
