Bucketman, FWIW, a SRG isn’t bonded to any particular point per se. They can be constructed of either the raised floor grid structure, #6 AWG copper conductor grid under the raised floor, a wire mesh embedded into the concrete or suspended from the ceiling, or a cable rack grid either under a raised floor or suspended from the ceiling. Lots of variables to work with. The important thing is the size of the grid. It depends on the frequency cut-off of interest. The grid is designed on 1/16 of the wavelength, so for a 30 Mhz grid you are looking at something with 2-feet on center. The higher the frequency the smaller the dimensions
As far as bonding or connecting, it is connected to everything like conduits, water pipes, every AC panel EGC bus in the area, all equipment frames, every XO in transformers, every building steel column it passes by, every ground electrode available, etc. The point is not necessarily low impedance to earth, but rather low impedance between any two points on the system and to the power source.
Edited to correct spelling
[This message has been edited by dereckbc (edited 11-05-2004).]