Selecting a Mounting System

In addition to the LED display itself, it is essential to select a high-quality mounting system, as this factors significantly into the appearance of the display. Ideally, the mount must be able to make up for inconsistencies in the flatness of the wall surface.

“The wall you are attaching to is never that precise, so you have to have a system that is able to mount to that non-flat surface and create a perfectly flat mounting surface for the LED panels themselves,” explains Grant Wylie, director of AV product management, Draper Inc., Spiceland, Indiana.

Consequently, the highest-quality mounts offer precision via Z adjustment for the structure, plus X, Y, and Z adjustments for every LED panel in the display. This then enables the face of an LED video wall to be perfectly flat all the way across, as minute adjustments can be made at the panel level. If the wall is not flat, seams in the LED will show, and the video wall will not appear seamless.

Tolerance should be within ¹⁄₁₀ of the LED panel pixel pitch. So if the pixel pitch is 1.2 millimeters from the center of one LED to the next, then the attachment needs to be able to maintain within 0.12 millimeter of tolerance in all axes from one panel to the next. This means that there needs to be some means to adjust every LED panel independently, in and out, on the mount so that the front face has that precision.

The Y-axis adjustment enables precise alignment up and down, and the Z-axis adjustment is the capability of the mounting hardware that allows the mount to stay flat while the wall fluctuates behind it.

Once the LED display and mount are selected, a well-designed and executed project requires a high level of planning. Toward this end, a number of questions need to be addressed, such as the following:

• Are lifts required for installation?
• Where is the access to the displays?
• How will the display be mounted and installed? On a wall or a floor stand?
• If the wall is built, are architectural drawings available?
• Is a bezel or shroud for the sides of the display required?
• Will the display be recessed into a wall?
• Where will the controllers be located in relation to the display?
• Is it close enough to run CAT, or does the contractor/vendor need to run fiber?
• Is a rack needed for the LED hardware?
• Is a light sensor/brightness sensor required?
• Is remote power control or a power conditioner needed?
• Is there three-phase power within 50 feet of the display location?
• Is power redundancy required?
• If indoors, has the HVAC been sized to accommodate the added BTUs the display will introduce into the environment?

Photo: Matt Oberer

Precise design and alignment are key components of a successful LED installation. Precision is required to preserve the LED’s seamless capabilities, resulting in a finished product that best represents the original design intent.

Mounting the Display

In mounting a display to the wall, most mounts and hardware can connect to most wall types, including wood stud, plywood, cinder block, concrete, and iron. That said, with concrete or block, it is important that the display is attached flat to the wall and not extending out in any way.

One wall type that does require additional work is a metal studded wall. Typically not designed to support an external load, these walls are often used in office retrofits where the existing walls are ripped out and a metal stud floating wall, not secured to the ceiling structure, is built. Consequently, any kind of counterweight would topple the wall over. To prevent this, the wall needs to be reinforced with bracing and plywood on the exterior surface.

If for some reason there are issues with attaching to a wall, mounting to the floor can be more cost-effective than reinforcing the wall. One type of floor mount is a structure that stands on its own, for example, in a hotel lobby. With a floor-mounted structure, the four key elements that must be determined are the floor type, the floor structure that will support the weight, how high the display will be off the floor, and the acceptable depth of the structure.

In attaching an LED display to the ceiling, if it is an existing build, the ceiling structure should be reviewed to make sure it can adequately support the weight. The display will then typically utilize a truss system to attach to the ceiling. Alternatively, it can be suspended with a rigging system. In either case, it is important that the support has backup safety measures in place.

For both wall and standing structures, there are additional considerations if the video wall is curved. A curved wall that is concave provides more depth and immersion, whereas a convex curved wall can wrap around a column. Essentially, a curved wall lets the design fit the space.

Curved walls can be faceted or smooth. A faceted wall uses flat LED panels to create a curve with brackets. The faceted curves require extremely precise structure and installation. That said, faceted walls are less expensive, easier to install, and allow for finer pixel pitches compared to custom-manufactured smooth-curved LED displays. However, they are not good for tight radii.

Smooth-curved walls are more aesthetically pleasing and present less drastic color shift from panel to panel. At the same time, a smooth-curved display does not support the finest pixel pitches, and installation can be more challenging. Smooth-curved LED displays can be either concave or convex.

It is important to point out that all LED panels have different mounting hole locations and sizes. Unlike LCD, there are no VESA mounting interface standards for LED mounting hole layout. Consequently, each LED manufacturer and each LED panel series has unique panel dimensions and mounting bolt-hole placement.

This essentially means that every display is custom manufactured, which means that the mounts must be custom designed for every LED panel and its attachment points. Some manufacturers have created mounting systems for specific LED panels, and some offer a mount that can scale up and down in size, and support any configurable size and aspect ratio.

As noted, the mount serves as the interface between a usually inconsistent wall surface and a very flat surface to which the LED panels can be attached. With precise X, Y, and Z positioning, the LED display presents a consistent, seamless look.

While a high level of precision is required of any LED video wall structure, this is especially true of NPP displays. The very tight pixel spacings—2.5 millimeters and below—create a detailed and crisp visual, so tight tolerances on the structure are imperative. LED video walls, by nature, are attention-grabbing displays and are frequently used to present some stunning content. Consequently, it is important that the structure not detract from the overall impression. To hide the visible edges of the structure, an attractive trim is required. Some manufacturers offer a black or matte black trim surrounding the LED panels to help the mount blend in and appear as minimalized as possible. If the design aesthetic is to achieve an industrial or mechanical look by showing the structure, then it should have an attractive finish.

Another issue is corrosion prevention/protection, even if for aesthetic reasons. Rust spots are very undesirable and could create a false impression that the structure is weak. To prevent this aluminum, galvanized coatings and properly applied paint or powder coat finishes can be used.

Yet another issue is determining if the LED display is front or rear serviceable. With the former, access is much easier, as technicians can go in, remove the LED modules on the front face of the display, access all of the components inside, and service them. In addition, the display can be installed flat to the wall.

While the vast majority of products are front serviceable, several manufacturers still produce rear serviceable systems. Because the LED display needs to project out from the wall to allow for access, this counterbalances the weight. Consequently, architects need to verify that the wall could support the structural load with the display extended out at its farthest distance from the wall.

When installing LED displays, the size of the modules can potentially pose a challenge to transporting the components to the installation location. For example, displays are frequently 20 to 30 feet wide by 20 to 30 feet tall, and components used to build the display need to be able to fit through a service elevator. Consequently, to enable transport in smaller sections, architects should verify that the components can quickly and easily attach together in the final installation location.

As part of the project delivery process, a detailed and outlined process of how the LED panels and mounting system will be transported and assembled together is an encouraged best practice. This includes the order of operation for building the system, installing the LED panels and the mount, and completing the finish work around the outside of the display. The installation location should be clearly vetted and marked, and during the installation, technicians should make sure that everything is square, level, plumb, and aligned properly. This entire process should be chronologically outlined and precise.

Photo courtesy of Draper Inc.

LED technology can create unique spaces and experiences. It is important that the supporting structure have the same flexibility and modularity to take advantage of LED’s capabilities.