The overhead conveyor in the paint shop slows to a crawl as the next car body approaches the dip tank. Inside the control cabinet, a compact electromechanical switch energizes, closing its main contacts without a single arc. This momentary signal diverts power to the three-phase pump motor that circulates the primer bath, ensuring the body is submerged at precisely the right speed. The same switch later reverses the motor to drain the tank when the line pauses for shift change, preventing sludge buildup on the freshly coated panels. On the final assembly line, identical switches sit inside the junction boxes of every automated screwdriver station. Each time a torque gun is lifted from its cradle, the switch interrupts the safety circuit, stopping the conveyor until the tool is re-homed. This interlock keeps the line moving only when every fastener is driven to spec, eliminating rework on door hinges and seat rails. In the adjacent press shop, a bank of these switches controls the large hydraulic pumps that feed the stamping presses. Their silent, repetitive cycling—engaging at 300 strokes per hour—maintains constant pressure in the accumulator, so each blank is formed with the same force whether it’s the first part of the shift or the thousandth.