Zero Speed Relays

Zero speed relays are safety devices designed to monitor the rotational speed of motors, conveyors, and other rotating machinery, ensuring they have completely stopped before allowing access or initiating the next process. These relays detect zero speed or underspeed conditions and provide a control signal to prevent unintended movement, enhancing operational safety. Commonly used in industrial automation, material handling, and heavy machinery, zero speed relays help protect workers and equipment by ensuring that moving parts have come to a full stop before maintenance or operation can proceed. They are essential in applications requiring strict safety compliance, such as conveyor systems, crushers, and mixers, where unexpected motion could pose serious risks.

For very heavy and hazardous machinery that does not stop quickly, a reliable safety signal indicating the machine’s stop is crucial for safety. Often, such applications use safety relays based on delayed timing. However, this approach may not always provide sufficient protection, which is why there are safety relays available that monitor stopping through two different techniques.