Vertical carousels & vertical lift modules – what’s the difference?

Vertical carousels, storage carousels, vertical rotating shelves, vertical lift modules – what’s the difference?

If you’ve been in the material handling business for a while, you may be familiar with the term “vertical carousel.” You might have heard it described as a storage carousel or vertical rotating shelf system – to differentiate it from a horizontal carousel.
Clear enough – one moves up and down, the other sideways.

No, it’s not. A vertical lift module is the more advanced application of the same function – automating storage by going up rather than sideways. This is a logical application when your storage facility has high ceilings, which translates into anything above 10 feet or so. 

Traditional storage systems don’t handle vertical height well. Either the shelves are low enough for operators to retrieve items from the floor or they require ladders or lift trucks to reach the higher parts. Either way, it’s a cumbersome and potentially dangerous process. 

An automated storage system that is taller than it is wide can optimize the use of that high ceiling while minimizing floor space requirements. However, there are important differences in how a vertical carousel works as opposed to a vertical lift module, commonly abbreviated as VLM.

Why people still call vertical lift module as vertical carousels 

Devices that are the first of their type often come to represent the entire category, even if the technology differs. For instance, people talked about “taping” something long after the devices using tape to record audio or video were replaced by digital devices. It’s the same thing with “vertical carousels,” which were introduced in the 1950s and sold widely. Vertical lift modules came later, but by that time, the term “vertical carousel” was fixed in the mind of many.

  • A vertical carousel stores parts on trays affixed to a chain that rotates. Like a Ferris wheel, it carries items of similar size and weight. A vertical lift module uses trays that move independently, like a vending machine. 
  • Vertical carousels have to be balanced so that too much weight doesn’t end up on one tray. Vertical lift modules do not have to balance weight and can retrieve items more quickly.
  • The shelves on a vertical carousel cannot be adjusted. So space can be wasted when tall items are stored on the same shelf as small items. Vertical lift modules can have trays of different heights. Small items can be store in one tray, while larger items in another, for instance. As a result, there is not waste storage space.
  • Vertical carousels are limited to heights of about 25 feet due to balance issues. Vertical lift modules can reach up to 50 feet or more.
  • Vertical carousels require the entire set of shelves to move, while the vertical lift module doesn’t have that limitation, so it is much more efficient to operate and has higher productivity.

While vertical carousels are still being manufactured, they are considered dated technology at this point. They represented an advance over traditional storage systems, but their day has largely come and gone.

In Conclusion

So if you’re in the market for an automated storage system, you probably want a vertical lift module if you have high ceilings or a horizontal carousel if you don’t. Modula offers both a full range of vertical lift modules as well as one of the most advanced horizontal carousel on the market. 

For more information on finding the right solution for your operation, get in touch! We’ll be happy to explain the many options we provide that can help you gain all the benefits of a vertical storage solution.