On traditional plugs and receptacles, the loosening of terminal screws is a common cause for failure. Most MELTRIC plugs and receptacles have patented, spring-assisted terminals that provide more permanent and secure conductor connections.
Pressure generated as the terminal screw is tightened against the conductor expands the split-terminal body and elliptically deforms the spring ring around the terminal. The spring ring, wanting to return to its original circle shape, exerts a constant pressure, pushing the terminal screw and conductor together. This constant spring pressure on screw and conductor helps
compensate for strand settlement and conductor
yield, while providing superior resistance to the
effects of vibration, shock and thermal cycling.