Personnel Safety, Crane and Hoist Workflow

Gemco application note on how-to Secure Personnel Safety, Crane and Hoist Workflow
Problem
Producers and users of large cranes need to provide crane safety in all aspects. An important part of safety on cranes and hoists is security by controlling the end limits of the crane or hoist travel.

This can prevent travel into a restricted area or damage to the hook cable drum assembly as well as the motor. This can lead to enormous expenses not just on repairing the gear, but a crane that does not work will often block the entire workflow in the area and may be a hazard to personnel.

Solution
For decades, Gemco have engineered, manufactured and marketed sensors and controls for demanding and harsh industrial environments, such as those found in the crane and hoist Industry. The geared rotary limit switch (RLS) provides upper, lower and intermediate limits for moving machinery and mechanisms. Gemco's line of rotary limit switches are designed for longevity, the units include all metal gearing and switches that are rated for 15 million operations.

The Gemco geared rotary limit switches are primarily used in material handling and rotary operations where motion is expressed in shaft rotation. The input shaft is typically connected to the motor or drive mechanism. After a set amount of turns, the cam trips the switches, thus starting or stopping the movement. The primary purpose of the switch is to control the intermediate or end limits in linear or rotary motion. The switch is often used as a safety device to protect against accidental damage to equipment due to overtravel on for instance cranes, winch drums, hoists or lifts.

Benefits
A simple geared rotary limit switch can easily save hundreds of thousands of dollars and prevent hours or even days of downtime due to overtravel.

Gemco Rotary Limit Switches (RLS) offer the broadest range of standard gear selections of any switch available. Standard reduction ratios range from 5:1 through 5333.3:1 or multipliers up to 1:3.

• Nema 1, 12, 4, 4X, 7, and 9 Enclosures
• 2, 3, and 4 circuit designs
• Rugged duty die cast aluminum alloy or fiberalloy (plastic) enclosures
• Optional - cast iron or naval bronze enclosures
• All metal gearing for longevity

Conclusion
What is the right rotary limit switch? Regardless of your application, selecting the right rotary limit swith is crucial. Acquiring a geared limit switch is not a costly affair, but the cost of a failure due to not using a limit switch can be extremely expensive.

Gemco has created a product selection guide, assisting you in the process of finding the correct way to protect workers, equipment and goods. The Product Selection Guide is available here.

To view the full application note, click here