Hand-crank horns are a reliable and power-independent alarm solution, ideal for use in areas without electricity. To activate the alarm, simply turn the handle clockwise manually. Once the rotation speed reaches 50-80 revolutions per minute, the alarm will produce a sharp, powerful, and penetrating sound. The volume of the alarm is directly related to how fast the handle is turned. The newer models feature an innovative shutter mechanism on the sound window, allowing users to quickly close it and control the sound output, enabling different signaling options—something not found in older versions.
The hand series alarms are compact, lightweight, and highly portable. They require no tools for installation and can be operated with just 0.15 square meters of space and a person standing nearby. Their ease of use makes them very practical for various situations.
These alarms are widely used in critical locations such as civil defense units, detention centers, prisons, mines, airports, pastures, oil depots, warehouses, hotels, and commercial facilities. In emergencies, they serve as an essential alert system.
Hand alarms are particularly useful for emergency warnings. Their portability makes them ideal for flood control, disaster prevention, forest fire response, military operations, and public or industrial emergency scenarios.
Traditional alarms typically rely on vibration sensors that trigger an alarm when any movement is detected. This can lead to false alarms from things like thunderstorms, animals, or even vehicles parked nearby.
In contrast, the hand-crank siren works by manually rotating a handle, which drives a gear system to increase the speed. This high-speed rotation powers a sounding wheel, generating loud, high-pressure sound waves. The alarm’s effectiveness depends entirely on the user's cranking speed—the faster you turn the handle, the louder and more impactful the sound becomes. Factors such as the user’s height, strength, and cranking speed all influence the alarm’s performance. For optimal results, we recommend a minimum cranking speed of 90 revolutions per minute.
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