Grounding and Bonding: Compliance with 2008 NEC Section 250.94
William & Patti FeldmanCompliance with Section 250.94 of the NEC, providing the means for "bonding for other systems" is an important part of an electrical installation in a residential, commercial, institutional, or auxiliary building or structure.
Though the NEC has, for several years, specified that ground conductors from multiple systems (such as telephone, CATV, computers, and other systems used by the telecommunications industry) be bonded together, until NEC 2008, the code did not specify how that was to be done.
The 2008 NEC code makes note of a device called "Intersystem Bonding Termination," defined as "a device that provides a means for connecting communication system(s), grounding conductor(s), and bonding conductor(s) at the service equipment or at the disconnecting means for buildings or structures supplied by a feeder or branch circuit."
UL 467 Listed bonding termination connectors that enable bonding termination in one location for all grounds (typically by the meter) in accordance with these NEC code requirements are available from several manufacturers.
For example, ILSCO ClearGround® Intersystem Ground Tap, type GBT, made of aluminum, provides an easy way to interconnect and terminate all communication grounding conductors. The lay-in style eliminates the need to cut or splice into existing conductor. No mounting is required which allows fast simple installation on ground conductor below meters.
Two sizes of ClearGround are available: the 1/0 main wire range is 1/0-8, tap wire range (4) 2-14 stranded-solid; 250 main wire range is 250 kcmil-8 stranded, 1/0-8 solid, tap wire range (4) 2-14 stranded-solid.
The stainless steel screws offer corrosion resistance while serrations in the conductor wire-way cut oxidation. A mountable product, with or without a cover, is also available.