Mar 20, 2015
Why Even Minor Increases in Contact Resistance Matter
When a contact is mated, only a relatively small area is actually touching.All of the current must flow through this small area – the actual contact interface.Because the current is constricted to flow through this zone of contact, the resistance associated with this current constriction is called “constriction resistance”.Connector designers understand that many variables impact contact area (normal force, materials, surface finish, environment, etc.), and how important this issue is for the contacts to adequately do their job.
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