Proper connection of the power terminals is critical to the long-term reliability and safe operation of high-voltage contactors, because improper installation can damage the hermetic seal, add resistance at the joint, and lead to premature failure. This application note explains why rigid busbar structures transfer mechanical stress into the contactor housing and can crack the seal over time, and why flexible laminated busbars are the preferred approach for absorbing thermal expansion and positional tolerance. It also covers fastener installation and torque, busbar mechanical compliance, and the firm rule against inserting washers, shims, spacers, or any other material between the contactor terminal and the conductor surface.
