High Power Lock Box terminals-SQ4


The SQ4 plug contact consists of a C15100 copper alloy without coating in the weld area. The application required welding both 35 mm 2 and 50 mm2 cables. The width of the weld area for the 50 mm2 variant was changed from 13 mm to 18 mm to enable a weld width of 15 mm. This also allows for a clamping width of 1.5 mm on each side of the plug contact when using a 15 mm sonotrode. However, the connector height of about 17 mm presents challenges for the sonotrode’s clearance for linear and conventional ultrasonic welding processes. It is not physically possible to design a linear sonotrode that can clear the 17 mm height and yet efficiently deliver the 20 kHz frequency as required.


The torsional PowerWheel® welding system was utilized to clear the connector height and achieve a superior quality weld for both 35 mm2 and 50 mm2 cables with the SQ4 terminal. The alignment of the sonotrode allows for the clearance to the plug contact and delivers sufficient welding energy to achieve a high-quality weld without affecting the finer wires in the transition area or the connection itself.

Configuration Advantages

The PowerWheel® technology approach allows the sonotrode to clear the connector and reach the cable for welding the SQ4 Royal Power Solutions plug contact. Since the torsional welding amplitude is at its peak in the center of the weld area, one can apply higher amounts of energy that may be required for welding a larger cable in cases of a smaller weld area. The quality control variables such as final weld height, welding time, and power are monitored for each cycle and controlled while production data is recorded for traceability.

High Power Lock Box terminals-SQ4

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