How to choose good terminal blocks? Here are a few points you should know

2025-11-18 09:22:32

Terminal block system: The task of the wiring system is to make reliable mechanical and electrical connections to the wires. The Weidmuller embossing frame can effectively achieve this function. This wire pressing frame is made of quenched and hardened steel that has undergone galvanization and passivation. The steel screws capable of withstanding huge torque can firmly press the wires. The copper conductive sheet is coated with a flexible tin-lead alloy, which can ensure an airtight, low-resistance and permanent connection with the wire. The following advantages of this wiring system are deeply loved by users and widely adopted:

One: It has a large contact surface, high contact pressure, and can be connected laterally at will. It has self-locking, anti-shock and anti-loosening functions. Test sockets can be installed and no maintenance is required. The contact points are absolutely airtight and corrosion-resistant. Multi-strand wires are allowed to be directly connected without crimping the ends. Easy to use; Widely adopted globally;

Two: High contact pressure: In terminal blocks, contact force is one of the fundamental elements. Even the best conductive materials will be of no avail if there is not enough contact pressure. Because, if the contact force is too low, displacement will occur between the wire and the conductive sheet, thereby causing oxidation contamination, increasing the contact resistance and leading to overheating. Take the WDU 2.5 wire frame assembly as an example. By applying a torque of 0.8 Nm to the screw, an actual contact force of up to 750 N can be generated, and the magnitude of this force has nothing to do with the cross-sectional area of the wire. Therefore, the adoption of Weidmuller wire-pressing frames ensures a permanent connection that is not affected by any environment, featuring a large contact area and high contact force.

Three: Small voltage drop: The magnitude of the voltage drop at the contact point is also one of the criteria for identifying the quality of the terminal block. Even when a very small torque is applied to the screw, the value of the voltage drop is still much lower than the limit required by VDE 0611. Meanwhile, the applied torque varies over a wide range, while the voltage drop remains almost constant. Therefore, although the torque magnitudes used by different operators vary, it does not affect the connection quality. This is yet another proof of the reliability of Weidmuller's creasing frames.