Profile: STS Instruments, Inc. manufactures surge testers, battery element testers, PC-based test systems and test fixtures for motors, windings, armatures & stators. Our surge testing offers the single test available for wound products. These testers detect insulation faults including turn-to-turn, layer-to-layer and phase-to-phase shorts. Our battery element testers verify the integrity of element separators by subjecting them to high voltage pulses.