What is the difference between ground and neutral from the perspective of the wall outlet working backward to the power company?
From the US homeowner's perspective of working backward from a wall outlet
o What is the difference between ground and neutral in the US?
A friend is debugging why the washing machine metal case is hot only when
the water pipes are hooked up and water flowing through them when I tried
to explain to that homeowner over the phone the difference between ground
and neutral - where - I'm not sure I have it all figured out myself.
I'm going to point her to this answer on the net.
*Is this correct for ground?*
o It's the round hole in a 3-hole outlet
o It's usually a bare copper wire (or sometimes green).
o It's connected to the sub panel without any breaks whatsoever.
o From the sub panel it connects to the main panel sans any breaks.
o From the main panel it goes directly to the main inlet cold water pipe.
o From that main cold water inlet pipe, it goes into a stake in the ground.
o It should never carry current unless there is a problem somewhere.
o Therefore, the voltage from it to the ground should be zero.
*Is this correct for neutral?*
o It's the taller slot in the typical grounded US outlet box.
o It's the white insulated wire (when black or red is the hot wire).
o It's connected to the sub panel but it may have connections between.
o From the sub panel it connects to the main panel sans any breaks.
o From the main panel it goes directly to the power company input.
o Generally that power company input will be a power pole.
o Within a few power poles will be the step-down transformer.
o From that step-down transformer the neutral will go into the ground.
o Therefore, the voltage from the outlet neutral to ground should be close to 0
In a way, they're similar in that both the ground and neutral eventually go
directly into the ground - but they're different in that the neutral
carries current while the ground only carries current when something is
wrong.
Before I point the homeowner to this thread, can you clarify or fix
mistakes in my understanding of the difference between neutral & ground?
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