R&M, the globally active developer and provider of cabling systems for high-quality network infrastructures, based in Wetzikon, Switzerland, is facilitating the introduction of Power over Ethernet to data centers and large networks with planning tools. Power over Ethernet (PoE) is used to power Ethernet end devices, such as switches, using data cables instead of separately laid power cables. Network cables can, however, also heat up under the influence of electricity. This in turn results in an increase in attenuation which reduces the transmission range. IT planners, technicians and data center operators must therefore carefully plan how to reduce the heating up of cables before they introduce PoE – for example with shorter links or smaller cable bundles. R&M supports planning with handy calculation tables. In addition to the configurator for fixed cables which is already available, R&M now also offers a configurator for patch cords. The free tool can be downloaded from the web.
"Power over Ethernet is spreading increasingly. Data center operators are also using the major advantages this technology provides even though this does entail the challenge of keeping the cables cool. This is not only true of the thick cable bundles behind the racks, but also the patch cords on the front," says R&M Product Manager Roger J. Karrer. The deciding factors: the cable cross section and the PoE performance levels used.
Thin cables are more susceptible to heat but users are increasingly opting for more slimline patch cords to reduce the cable volume at the front of the rack and facilitate patching. For example, the new PoE-capable R&MthinLine patch cord range is very much in demand. Its slimline cables have a total cross section of just 3.8 mm or 4.5 mm and conductor diameters from AWG28 to AWG30. This is why R&MthinLine cords are more flexible than conventional ones. They are easy to lay in tighter bending radii and are simple to store in cable guides.
Roger J. Karrer emphasizes: "This combination of PoE and thin patch cords pays particular attention to the possible increase in temperature and planners are given plenty of support by the PoE patch cord configurator from R&M." The configurator calculates the end temperature to be expected in the patch cord bundle for each planned PoE performance level. These range from 15 watts to 4PPoE (4-Pair Power over Ethernet) with a 55 or 100 watt output. With 4PPoE up to half an ampere can flow via each twisted pair, which can cause overheating in long, very chunky cable bundles. The configurator takes ten parameters, such as room temperature and the volume of the cable bundles, into consideration. Planners can derive tolerances from these and see when critical temperatures will be reached in the patch cord bundles.