Belden explains: How TSB-184-A supports Power over Ethernet

July 7, 2017
Belden’s Ron Tellas breaks down the most-salient aspects of the TSB-184-A standard document recently completed by the TIA.

In a post to the Belden Blog, the company’s manager of LAN technology and applications, Ron Tellas, boils down the recently completed Telecommunications Systems Bulletin TSB-184-A Guidelines for Supporting Power Delivery Over Balanced Twisted-Pair Cabling.

In the post, Tellas reminds us that in Power over Ethernet applications, “a small percentage of the power being carried over the cable is dissipated as heat inside the cabling.” He further explains, “Putting cables into bundles can heighten this temperature rise. Cable temperature rise can push cables past their rated temperatures, reducing performance and reliability (and possibly damaging the cable). Controlling temperature rise will decrease potential cable problems and network performance issues.”

The specifications in TSB-184-A are intended to do exactly that—control temperature rise and thereby decrease potential problems. Tellas points out that TSB-184-A is a set of guidelines, which are intended to be used in addition to ANSI/TIA-568 infrastructure requirements.

TSB-184-A “supports power delivery using all four pairs, with up to 1000 mA per pair for a maximum power of 100W,” Tellas points out. He then identifies the following specific recommendations from the TSB.

  • Leaving cables unbundled to facilitate better heat dissipation—if not possible, small bundles are recommended
  • Limiting the number of cables per bundle to 24 to reduce potential temperature rise caused by installation factors, high ambient temperature, 26-AWG cables and higher currents
  • Using Category 6A or higher-performing 4-pair balanced twisted-pair cabling for new PoE installation

Tellas also states, “As power demands for IP-enabled devices grow, so will the demands placed on your cable, and your network. The current PoE standard, IEEE 802.3at, allows for 30W of power at the source. The proposed standard, IEEE 802.3bt, allows nearly 100W of power at the source. It is expected to become a standard in 2018.”

You can read Ron Tellas’s full blog post here.

Sponsored Recommendations

Power up your system integration with Pulse Power - the game-changing power delivery system

May 10, 2023
Pulse Power is a novel power delivery system that allows System Integrators to safely provide significant power, over long distances, to remote equipment. It is a Class 4 power...

Network Monitoring- Why Tap Modules?

May 1, 2023
EDGE™ and EDGE8® tap modules enable passive optical tapping of the network while reducing downtime and link loss and increasing rack space utilization and density. Unlike other...

400G in the Data Center

Aug. 3, 2022

The Agile and Efficient Digital Building

May 9, 2023
This ebook explores how intelligent building solutions can help businesses improve network infrastructure management and optimize data center operations in enterprise buildings...