counterpoise grounding system
this is most common ,to commercial or industrial type electrical work on every job we do it everyday .meaning every new construction job we do it , your service ground rods your grounding mat in sub station or yard in most commercial buildings all lighting protection meaning lighting rod down leads attach to a counterpoise 3 or 4 feet off the exterior of a building and 2 to 3 foot down below grade ,continuous cad weld connections are made at each down lead it is mostly 3/0 copper braid conductor and bare no insulation ever, bends are made with long radious not sharp. any grounding in the building connection is made to this counterpoise loop around the entire building or yard . main service ground rods are installed delta but then a connection is made to the counterpoise loop ,building steel ,rebar in footers uffer , most large concrete structures like in cooling towers or like structures will have a counterpoise ground system . the grounding or counterpoise is like a grid in a sub station yard mat no one ever sees it but its there many loops run in a grid pattern every structure is hit miles of copper run . take your main grounding connection from your mcc or electrical room ground bar or loop to that intake water platform metal deck with what size the drawns show on your one line normally it will be a copper but may need a connection spec by your job detailed sheets drawns of your grounding system it maybe a flex type mechanical connection ask your foreman or leadman but its a simple ground connection and nothing more. but you may need a sea cable in this case to run it in at lake bottom under water does this float plat have power to it or control to it? a counterpoise loop system means you have a equal balance of potential to ground earth. earth by itself is not good enough basically between ground points ,we tie everything on our job to it. if we have 8 buildings or structures or towers or ducks banks running from building to building we run a bare ground on top of duck banks some duck banks require 3 bares run on top with added ground rods every 50 foot running with duck banks . this ties into the counterpoise and also goes to the main ground bar mounted on the wall of that electrical room or rooms these copper ground bars are 6 inches high 3 foot in length and 1/4 thick every ground in that room is cad welded to it , cable trays conduit ends that run out of trays transformers , voltage regulators , battery trays ,control i/o cabinets ,data centers , main control rooms metal walkways stairs ,boilers ,motor frames every electrical system ties even the doors to some rooms !! and each sub room in that building are looped together it its called Equipotential . hope this helps good luck best to ya
Last edited by nick; 07-31-2008 at 05:16 AM.
Reason: well i cant spell never learnd how
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