... 50HZ,Three-PhaseSafety Device: Emergency Stop Switch, Over-speed Limiter, Rope-breaking Device, Top-limited Switch, Manual Descend. ... 50HZ,Three-PhaseSafety Device: Emergency Stop Switch, Over-speed Limiter, Rope-breaking Device, Top-limited Switch, Manual Descend. ... 50HZ,Three-PhaseSafety Device: Emergency Stop Switch, Over-speed Limiter, Rope-breaking Device, Top-limited Switch, Manual Descend. ...