By David G. Hevey, Warner Cable Communications Inc.
With higher bandwidths and increased gain, today's generation of active equipment consumes more power than the previous generation. The methodology behind powering this equipment, however, has remained essentially the same. Power supplies are added to the plant to compensate for the expected additional load or for potential future modifications. Along with additional power supplies, however, comes a decrease in system reliability. A power supply is dependent on the integrity of the local utility, and, based on our standard TREE AND BRANCH architecture and resistance to standby power, our reliability can never be better than theirs. To achieve satisfactory reliability, power supply cascades, or the number of power supplies serving a subscriber, must be reduced.
Headend operations are likewise impacted by power outages. In addition to the interruption in the cable service, the down time can contribute to headend equipment failures.
This paper introduces an alternative to the standard method of system powering. Described as a HARDENED TRUNK, it is a highly reliable, low maintenance, method of powering a cable plant. It offers relative ease of implementation, additional equipment protection, and, most of all, fewer power outages.