The 2CPSA1A1 is a four-pole single-throw (4PST-2NO) double-pole single-throw (DPST-NC) 1/2-inch NPT Cable Pull Safety Switch provides a readily accessible emergency stop signal. It is designed to provide emergency stop protection for exposed conveyor and assembly lines. The internal mechanism latches on both slackened cable (push) and pulled cable. This capability also enhances productivity by eliminating nuisance stops due to variations in temperature, stretch of cable over time and other application variables. It is intended for use in very long cable runs of 152m (500ft) or shorter, such as long conveyor lines found in warehouses. A line in the midpoint of the cable tension window indicates proper cable tension, providing easy set-up. The direct opening switch contacts are held closed when the actuating cable is under proper tension and the reset knob is set to RUN. When the actuating cable is pulled, slackened or broken, a cam positively opens the NC switch contacts.