It is possible that no two terms create so much controversy in the telecommunications industry as ‘grounding’ and ‘bonding’. Ask ten people and it is a good bet that you’ll get ten different definitions that, more than likely, are more opinions (if not guesses!) rather than a good technical definition. And relying on the National Electrical Code to define them for us? GOOD LUCK! The most recent versions of the Code are even less of a help (it simply says grounding is ‘the earth’). The key to understanding them is their intent.
Let’s keep it simple, shall we? Here’s the two terms in a nutshell…
‘Grounding’ – Grounding is the actual mechanical connection to earth for the electrical system/equipment, known as the ‘grounding electrode system’. With the exception of outside plant (OSP), this connection is made for us by the electricians. The purpose of this system is to act as a voltage reference for the electrical system. It also provides a path for lightning stroke currents and static discharge currents that may be present on, or in, the building. But, more than anything, think of it as an anchor…everything is referenced to it!
‘Bonding’ – Bonding is the joining of metallic surfaces, via conductor or mechanical connection, for the sole purpose of equalizing potentials during lightning, ground faults, static discharge, electromagnetic interference, and other issues. In other words, it will equalize potentials while other components in the grounding system are doing their job (i.e., while the Earthing System is diverting lightning energy or the Equipment Grounding System is carrying fault current, etc.).
Let’s put it this way…if you’re in structured cabling telecommunications, you’re bonding ONLY! A question often asked is, ‘What if I’m connecting my busbar to building steel? Is that ‘grounding’?’ The answer is ‘no’ because you are bonding to a grounding electrode that’s already been established for the building.
If you’re looking for more information on this subject, iGround has several grounding and bonding courses, including unique ‘hands-on’ classes to meet your training needs. Contact us today for information on putting together a custom solution to build upon your team’s educational experience.