3 ms·

> and some random line worker may think there's no electricity flowing when there is. If you have lines in an unknown state, step 1 is to put them in a known s

by Syonyk 4y ago

> and some random line worker may think there's no electricity flowing when there is. If you have lines in an unknown state, step 1 is to put them in a known state. For power line work, this involves grounding all the phases and neutral together at both ends of the section you intend to work on. Good luck ringing a dead short with your home inverter/generator/etc.

benj111 4y ago
Off topic but I've always thought of grounding as conceptually making the entire earth a part of the circuit and so dispersing the energy over a very large area. Is that conceptualisation correct? What happens is you have say a conductive (iron rich) top layer. Is there still the potential to dangerously energise the ground? I assume so because that's basically what water and electricity does?
- everforward 4y ago
  Not an electrician, so someone else may have better info. Grounding provides an alternate path for the flow of electricity, so if a wire comes loose and ends up touching a copper pipe or something the current gets routed into the ground rather than into pipes or flammable wood or something. Dispersal over an area isn't directly the goal, but it helps. By dispersing the current into an extremely large object, you don't really have to worry about the object building up a charge to the point where you can't flow current into it anymore. Yes, you can dangerously energize the ground. You can dangerously energize almost anything with enough voltage. E.g. a Tesla coil has enough voltage to conduct through air. Don't try to test it (obviously), but I don't think a standard 110V house grounding has enough voltage to dangerously energize ground over any significant distance.
- gubby 4y ago
  Grounding isn't really about dispersing energy over an area, it's about creating a situation where faults can be detected and circuits automatically opened to prevent shocks or fires. It actually gets very involved to reason through the exact purpose of ground connections when you start considering all the different types and combinations of faults (indoors, outdoors, person in contact with true earth, person touching exposed metal pipe, etc etc).

by Syonyk 4y ago

benj111 4y ago

Off topic but I've always thought of grounding as conceptually making the entire earth a part of the circuit and so dispersing the energy over a very large area. Is that conceptualisation correct? What happens is you have say a conductive (iron rich) top layer. Is there still the potential to dangerously energise the ground? I assume so because that's basically what water and electricity does?

everforward 4y ago
Not an electrician, so someone else may have better info. Grounding provides an alternate path for the flow of electricity, so if a wire comes loose and ends up touching a copper pipe or something the current gets routed into the ground rather than into pipes or flammable wood or something. Dispersal over an area isn't directly the goal, but it helps. By dispersing the current into an extremely large object, you don't really have to worry about the object building up a charge to the point where you can't flow current into it anymore. Yes, you can dangerously energize the ground. You can dangerously energize almost anything with enough voltage. E.g. a Tesla coil has enough voltage to conduct through air. Don't try to test it (obviously), but I don't think a standard 110V house grounding has enough voltage to dangerously energize ground over any significant distance.
gubby 4y ago
Grounding isn't really about dispersing energy over an area, it's about creating a situation where faults can be detected and circuits automatically opened to prevent shocks or fires. It actually gets very involved to reason through the exact purpose of ground connections when you start considering all the different types and combinations of faults (indoors, outdoors, person in contact with true earth, person touching exposed metal pipe, etc etc).