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Hey everybody, this is George with Argo electrical services. And I am the surge protector guy. So this is actually podcast number 11. And this is our third podcast on ground and grounding. This is part three, this is the final one we’re gonna do on this right now, by no means have I covered everything that needs to be just discussed with grounds and grounding or bonding. But I just wanted everybody to kind of get you know, these general ideas, I would say this, you know, if you do not understand some of the terms that we’re talking about, get yourself a National Electrical Code Book cost you about 100 bucks. If you’re doing this kind of work, you need to understand grounding, okay, and if you don’t understand what you’re reading, get you a dictionary, get in front of a computer with Google and Google it and read some articles on that. Maybe you can find someone that’s more eloquent than I can to explain it to you. But anyway, here’s some here’s some major of points, you know, for understanding or takeaway grounding and bonding, first grounding and bonding limits over voltages, they stabilize the voltage to ground during regular operation, and they do improve the performance of overcurrent protective devices. The grounding path from current equipment and metal enclosures to the supply source must be continuous, not subjected to damage and capable of carrying the fault currents imposed upon them. The impedance of the fault current path must be low enough to generate sufficient fault current to actuate the overcurrent devices protecting the circuit the Earth is not an effective fault current past the arrangement of the electric system must prevent objectionable current from flowing through the grounding and bonding paths grounding and bonding equipment must be adequately connected and located where it will not undergo damage, good electrical continuity in the contact surfaces is a must. So the grounding path from circuit equipment and metal enclosures to the supply source must be continuous. That means if you’re you’re using those to ground that means you need to have jumpers from your metal conduit connectors to the actual casing of the metal box or raceway. It also means that you know, that you can’t go from Metro to PVC and back to metal and back to PVC because then you can’t count on the metal to you know work as you know, a grounding path the impedance of the fault current must be low enough to generate sufficient fault current to actuate the overcurrent devices protecting the circuit. So you know there are a lot of different breakers out there when you get in an industrial grade breakers. There are settings on the breakers where you can set it to you know, you know, we did some starters the other day on this trolley at Lake Lanier that allowed people to ride up and down he’s very very steep heels to the lake and the star do had you know you could set anywhere from you know like three amps all the way up to 30 amps on there. So if you got in a certain range, it would trip it before you burn up the motor right and the impedance of the fault current path must be low enough to generate sufficient fault current to actuate the overcurrent devices. If that is not low enough, the overcurrent device will not work. Therefore you have no safe device. I can remember many many moons ago I’m no match 2530 years ago when I worked on Piper meals down in Savannah, Georgia and there were just a rooms and rooms of panels. And I’m talking about miles of conduit of hot circuits. We had no idea where they would go and guys would actually you know try to trip a breaker to where they could work on a circuit or whatever. And at some point these overcurrent devices were so old and And the fault current impedance you know was not low enough to generate a fault current and they would not trip the breaker it’s very dangerous situation and the the arrangement of electrical electric system must be must prevent objectionable current from flowing through the grounding and bonding parts. That means the way that it is your system is designed when you build it, it has to it has to flow just like we talked about, you got a positive on one side and a negative on the other side and they’re racing around the copper wire 100 degree 180 degrees in infinity you know back into back into back into continuously and you know and if there’s a problem, you know, it needs to be able to trip the breaker grounding and bonding equipment must be adequately connected and located where it will not undergo damage. That means the the ground does not get disconnected. Just like we talked about alternative paths to ground. Good electrical continuity in the contact surfaces is a must. My name is George I’m with Argo electrical services. I am a surge protector guy. You can find me on the web at Argo electrical.com Thank
