Fatigue Applications

Electrolytic copper foil has an inherently poor fatigue life. Whenever possible, orient the long dimension of the copper terminal along the axis of minimum strain. If the strain level exceeds + 500 microstrain, and if the terminal installation must have a long life under cyclic loading, use the 'C' configuration terminals cut in half as shown below. This reduces the bonded length of the terminals, and allows the same solder mass to join both sets of wires. Failure of the copper between solder joints is prevented by this technique.

Note: When the main leadwire is stranded, it is often convenient to cut all strands but one to fit the size of the copper pad. The long strand can then be used as the jumper wire. Soldering is made considerably easier by the method.

Page 5 of 12