VoIP Growth Spurs Current Boost
by Michael O’Connor,
Hubbell Director of Technical Marketing

The rapid growth of voice over IP (VoIP) and wireless systems has driven the consumer’s need to insert power onto the data cabling plant and avoid installing a separate electrical circuit. When Power over Ethernet (POE) is sent, it is very important to preserve the quality of the data and voice information being transferred. Although most VoIP systems operate with about 60 milliamperes (mA) of current, the standard presently being developed to support this application allows up to 350 mA, because that is the cable’s maximum capacity.

Connection Hardware Standards
Connection hardware is needed to meet and exceed this capacity in order for the system to work properly. The current capacity of connecting hardware is determined by the thickness and the width of the current-carrying traces in the circuit behind the connectors. Design rules suggest that a 0.0015” thick (1 oz) trace that is 0.015” wide is capable of handling 550 mA. Hubbell Premise Wiring’s connecting hardware products have always been designed to exceed all minimum requirements for current carrying paths. In addition to the UL and NEC safety standards Hubbell connectors are subjected to the next level of assurance: The ability to continuously conduct required current levels without overheating and reducing the electrical performance.

Putting it to the Test
To show customers that its connecting hardware products are prepared to exceed all requirements established, Hubbell subjected a variety of its SPEEDGAIN™ 5e jacks and patch panels to current capacity testing under extreme conditions. Approximately 700 mA (double the proposed specification) was passed through all connections at the same time and applied to all eight conductors instead of only four as would be done in normal operation. Each sample was energized for a minimum of three hours to stabilize the temperature after reaching a maximum. Temperature readings were made every hour and ambient temperature recorded. Results showed that the temperature rise for all test samples was minimal. The testing performed demonstrated that Hubbell’s connectivity is fully capable of handling the current carrying requirements by exceeding the proposed specifications without any substantial increase in temperature or failure. Hubbell’s connector design philosophy has been focused not only on exceeding the standards, but also on anticipating the needs and possible applications using connecting hardware. As such, the details of design, material choices, trace and contact routing, as well as other proprietary design techniques have been maintained with the goal of supporting power delivery. In particular, the trace dimensions and separation are optimized to provide maximum heat dissipation for reliable, safe, continuous operation.

Published by Anixter Inc.
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