Cable retractor reel - safely supply energy with e-spool®

The igus® e-spool® is an alternative to traditional cable reels, which are used to guide cables and hoses in confined spaces. The e-spool® system can guide several cables or media lines, including power, control or pneumatics, in one reel. In most cases, the e-spool® runs without electrical power, making it very easy to use, but for some unique applications it can also be developed with a motorised drive solution. It is easy to install, flexible, space-saving and extremely reliable. The system is designed with two different igus® energy supply systems in an innovative way. First, a standard igus® E2/000 e-chain® is guided on a steel spool. An integrated retraction spring within the spool provides retraction force and manages any slack. Additionally, an igus® twisterband connects the rotating spool to the base structure, where the fixed cables enter the system. The twisterband is what makes the e-spool® truly unique, as it eliminates an array of complications that typically come with other cable reels.

In traditional cable reels, a cable is run from the source (panel box, PLC, etc) to the fixed point of a slip ring. A second cable is then run from the rotational point of a slip ring to the end effector (lighting truss, assembly tool, etc.). This requires two lengths of cable, with four ends to be terminated. More terminations mean more installation labour and more points of potential failure. In an e-spool®, a single continuous cable is run from the source to the end effector without any intermediate terminations, improving the quality of the electrical signal and minimising the risk of failure. The e-spool® is also designed to be much more versatile in what types of energy it can carry. In traditional cable reels, only one cable can be used per reel. Traditional solutions also require different types of reels for different energy sources, which have different form factors and must be purchased from multiple different suppliers.

The e-spool® design is also optimised for extended service life. It is expected to achieve between 70,000 and 200,000 strokes, depending on the application, while traditional cable reels often require service at a lesser number of cycles. In the igus® test lab, the e-spool’s® spring was tested in respect to its service life expectancy and the results were superior. In all tests, the e-spool® achieved a minimum service life of at least 70,000 strokes. Once maximum service life is reached, only the spring pack must be exchanged, which is a short 15 minute service effort. Once the spring is replaced, the e-spool® is ready to deliver another full service period, with all other components lasting for an extended period of time.

Along with the technical benefits of e-spool®, the cost can also be lower than traditional solutions. Light-duty industrial cable reels can be offered at a very low cost, but they are not rated for automated operation. Medium-duty industrial cable reels rated for automated operation are only slightly less expensive than e-spools®. However, since traditional industrial reels can only guide one cable per reel, the costs become much greater when multiple cables are involved. Since the e-spool® can handle multiple cables in one reel, overall costs are likely to be lower in these scenarios.

The e-spool®’s quiet operation is another reason that it is well-suited for noise sensitive applications such as stage installations. In the igus® test laboratory, which is the largest in the industry, the e-spool® was intensely tested for its noise emissions during operation. The e-spool® was able to reach noise levels below 46dB (A) in the test - incredibly quiet results.

Aside from the standard offerings, igus® develops customised solutions as well. There are standard systems available with special additions, including systems with tubes, RBR chains, and stainless or coloured systems. There are also more custom-built options, including e-spools® designed for longer travels, systems with a different chain or custom changes to the steel parts to better integrate to a customer’s machine.

The unique structure of the e-spool® can put some mechanical stress on cables, so in order to help relieve these strains, there are a few guidelines that should be followed when filling an e-spool® with cables. Shielded cables designed for continuous torsional flexing such as chainflex® CFROBOT cables should be used when the maximum possible service life is desired. Cables should be placed side by side in the linear chain and never stacked on top of each other. Wherever possible, separators should be used to protect cables from becoming crossed or tangled. Cables should also be inserted according to diameter and/or bend radius, with the smallest cables towards the inside of the carrier and the increasingly larger cables towards the outside. Strain relief should be installed at both ends of the cable.

Though slip rings provide a functional solution to transfer current through a rotational junction, they are sensitive to external and environmental factors such as dust, dirt, moisture or other forms of contamination, and require regular maintenance to remain operational. There are various problems that can lead to maintenance or complete replacement of slip rings, with the most common issue being wear or threading of brushes. As the brush wears down, it wears fine grooves into the contact ring, while also covering the inside of the slip ring in fine dust from the brush wear. The brushes themselves and their retaining springs must then be replaced, which can be a messy and tedious process that also requires powering down the electrical system to safely work on the internal components. Loss of contact between the brush and the ring is another cause of failure, which can cause unexpected faults in production machinery or interruption of electrical current in the case of a lighting truss or similar application. Copper or steel slip rings are also inclined to corrode in wet or outdoor environments, especially if they aren’t properly sealed, further increasing the risk of failure. In short, slip rings are simply prone to overall wear, therefore increasing the likelihood of ongoing problems and the need for regular maintenance.

When to use the e-loop® system:

• When many different cables should be routed in very confined spaces
• When different media (power, data and fluids) can be routed together in one system

When to use another system:

• For cables with large bend radii
• With very high loads that have to be guided vertically
• With overhead applications in a public area

Cable reeling drums are typically found in the grid section of the theatre / Auditorium, Floor mounted, then using a bespoke roller system and guide hole through the grid floor, the cable management system is then connected to the ladder truss / Bridge.

Our e-spool® uses our twisterband, which is fixed on the side of the cable drum, acting as a secondary cable management system. The twisterband offers great rotation movement in very small spaces so the e-spool® can be used in a confined area as well as offering a hardwired maintenance-free cable management system.

• When many different cables should be routed in very confined spaces.
• When different media (power, data and fluids) can be routed together in one system.

• For cables with large bend radii.
• With very high loads that have to be guided vertically.

Traditional retractable cable reels store cables on a drum inside the housing. When you pull the cable out, the drum rotates and a tensioned spring (or motor in powered versions) stores energy. Release the cable, and the spring rewinds the drum, pulling the cable back in. Many reels include a locking mechanism so you can fix the cable at your desired length.

To maintain electrical continuity while the drum rotates, conventional reels use slip rings. However, slip rings can wear out over time and limit the transmission of media such as air or fluids.

igus® e-spool® changes the game.
Instead of slip rings, e-spool® uses a unique twisterband and spiral guide system to keep cables continuously connected without interruption. This allows safe transmission of power, data, and even media like air or fluids.

Inside the reel, an igus® energy chain ensures cables maintain their minimum bend radius, reducing wear and extending service life. When not in use, the chain rolls up completely, saving space and keeping floors clear. e-spool® works in all directions — horizontal, vertical, or diagonal, and is available in multiple variants:

• e-spool® flex 2.0 for single cables or hoses
• Manual, spring-driven, or motorised options for different applications
• Smart monitoring with i.Sense and i.Cee

Compact, flexible, and durable, igus® e-spool® is the ultimate solution for safe, space-saving cable management without slip rings.