Design of a Testing System of Sliding Electrical Contact

To study the sliding electrical contact phenomenon, a four-channel testing system is designed to simulate sliding process of electrical contacts, including a mechanical unit, a measuring unit and a controlling unit. In this testing system, the sliding stage is driven by a slider-crank mechanism to generate 1-2.2 cm reciprocating sliding at 0.5-2 Hz frequency between a pair of simulated contacts. A novel loading structure of double diaphragm springs is designed to supply 0-3 N normal force for each contact pair. By four-point method, contact resistance of 40 points is measured in one sliding cycle and is collected by an NI data acquisition card. Lab VIEW software is used to control the stepping motor, select test channels, measure contact voltage, process resistance data and display resistance curves in real time. Sliding simulation results prove this sliding test system to be credible and stable.