2020 NEC - exhibit 250.12 for grounding

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shespuzzling

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new york
When I look at this exhibit, I see a return path for current back via the equipment ground path in a normal condition (marked up in red). Maybe my misunderstanding is that the connection I circled in blue isn’t necessarily a continuous path? Any help appreciated!
Thanks
 

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Up to and including the main service disconnect enclosure, the neutral/grounded conductor and any metallic conduits, enclosures, troughs, other raceways, etc., are considered to be one and the same.

They, along with the grounding electrodes, establish, or re-establish the zero-volts reference point for the service and the premises equipment grounding system. That's "earth" for all intents and purposes.
 
Thank you, so it sounds like it’s true that current during a normal condition could return via the path I showed in red, but this is acceptable by code for this specific situation since we are service equipment?

If that’s true, could that lead to shock potential if a person touched the service trough (for example) and there was current flowing through it?
 
shespuzzling said:
Thank you, so it sounds like it’s true that current during a normal condition could return via the path I showed in red, but this is acceptable by code for this specific situation since we are service equipment?
Click to expand...
Yes it's acceptable and required to connect all of the metal parts upstream of the service disconnect to the neutral.

shespuzzling said:
If that’s true, could that lead to shock potential if a person touched the service trough (for example) and there was current flowing through it?
Click to expand...
Under normal conditions there should be no shock potential.
 
shespuzzling said:
f that’s true, could that lead to shock potential if a person touched the service trough (for example) and there was current flowing through it?
Click to expand...
The only voltage to provide a shock hazard would be the voltage drop as a result of the current flow on that path. Very unlikely that there will be enough voltage drop to result in a shock hazard.
 
shespuzzling said:
Thank you, so it sounds like it’s true that current during a normal condition could return via the path I showed in red, but this is acceptable by code for this specific situation since we are service equipment?
Click to expand...
Absolutely.

shespuzzling said:
If that’s true, could that lead to shock potential if a person touched the service trough (for example) and there was current flowing through it?
Click to expand...
Read my second paragraph again.
 
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