JESSUP, Md., March 14, 2018 /PRNewswire/ -- At Tate, we're consistently getting questions from potential clients about how load capacity for a raised access floor in a data center is calculated. For example, how can a rack of IT equipment weighing 4,500lbs be adequately supported by ConCore 3000 panels which have a design load of 3,000lbs? After all, 4,500lbs is more than 3,000lbs, so shouldn't the client use a panel with a higher load capacity?
It's easy to understand where that confusion can come from and, while many of our data center clients may be structural engineers, you don't have to be to understand the basics of how access floor panel load capacity works in the field.
The first thing to understand is that not all loads are created equal; there are numerous types, all of which look at the topic from a slightly different angle. Tate applies CISCA testing methods with panels installed on actual understructure (this more accurately represents an installed access floor system) to determine what is called Design Load or Working Load. This is the load that can be safely applied without experiencing permanent distortion of the panel – in the case of our ConCore 3000 panel from the example above, the Design Load is 3,000lbs.
But in this example, and many other cases like it, what is of equal importance to the Design Load of the panel is the Point Load created by the equipment itself.
That 4,500lb rack doesn't have a uniform load distributed equally across the bottom surface of the rack, but rather four feet – or points – one on each corner, through which the total load is distributed equally. Now, some racks have casters rather than leveling feet, and we'll talk more about casters in a moment, but first let's look at the implications of IT equipment Point Load and how it works with the Design Load of an access floor panel.
From a mathematical standpoint, Point Load distribution can be expressed by taking the total weight of the rack and dividing it by the number of points, or 4,500 / 4 = 1,125 lbs per point. What the raised floor panel sees is the load presented at the point – or points, if a single panel is supporting two leveling feet on adjacent racks (in which case you're looking at a total Point Load of 2,250lbs). Either way, you're still well within the 3,000lb Design Load of a ConCore 3000 panel. An easy rule of thumb to remember is that, independent of how many points you may have on a single panel, if the total Point Load doesn't exceed the Design Load of the panel – you're good.
But what if your data center is utilizing racks on casters rather than leveling feet? Well, the Point Load calculation for a rack on casters is completely identical (4,500 / 4 = 1,125), but a caster presents a new load type: Rolling Load. Like a leveling foot, each caster represents a bearing point on the panel. Unlike a leveling foot, which keeps the rack in a fixed position, four casters will allow our hypothetical 4,500lb rack to be rolled across the floor. A panel with a 3,000lb Design Load will always have a slightly reduced Rolling Load capacity. In the case of a ConCore 3000 panel, the Rolling Load is 2,700 lbs with a 10 pass test, and 2,400 with a 10,000 pass test. Which Rolling Load you want to take into consideration depends on how often your equipment will be moved but, either way, a 3,000lb Design Load is plenty of support for one (1,125lbs) or two (2,250lbs) casters moving across the panel at a time.
And that doesn't even take into account that every panel manufactured by Tate has a minimum Safety Factor of 2, meaning it can withstand a load of at least two times its Design Load – in this case, that would be 6,000lbs – before failing (once again, these numbers are all generated through testing conducted in accordance with CISCA standard testing methods).
As this example illustrates, while there may be a lot of factors at play, it's easy to get a basic grasp on how load capacity really works. Of course, when it comes to preparing the specification for your next project, it's vital to ensure proper load capacity. That's why Tate set up a 1-800 number to allow customers direct contact our engineering and technical support teams for assistance and information at any point during a project.
SOURCE Tate Access Floors