What is a Pull Force Test?

A pull force test is a crucial evaluation method for wire terminal crimping quality, ensuring that the mechanical bonding force between the conductor and terminal meets safety standards. During the test, a pull tester applies tension at a fixed speed until the terminal separates from the conductor, and the maximum pull force value is recorded. This test effectively detects crimps that are too loose or too tight, preventing unstable current or signal interruption due to poor contact.

In quality verification, different wire diameters and terminal types have corresponding standard pull force values, often performed according to IPC WHMA 620 or customer specifications. A pull force test ensures that the wire harness maintains structural integrity during actual assembly, handling, or long-term use, reducing the risk of electrical and mechanical failure.