# Power Outlet Signal

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My grandpa asked me a question regarding the signal coming out of a power outlet. We know that the ground hole is always ground, and that between the two power holes there is a 120 Hz sine wave signal. However, I don't know how exactly is that signal sent. That is to say, what are the node voltages at the holes? Is one hole giving the whole range of voltages while the other just stays at ground level (figure 1)? Or does each hole provide a staggered half-rectified sine wave (figure 2)? Thanks in advance for any help.

Figure 1:

2:

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Though I don't understand your drawing, this one is closest. Assuming everything is wired correctly and there are no faults in the system, you're correct the "ground" pin (the round one) is grounded. ;-)

The "neutral" pin (the left, larger, one, if looking at an outlet with the ground pin down) is also tied to ground at the service entrance panel. It may not be precisely at ground but should be very close (again, assuming no faults). The "hot" pin (the right/smaller pin) has 120VAC on it. The voltage on this pin will swing from 0V to +170V to 0V to -170V, 60 times a second.

No, this would cause all sorts of unnecessary grief, and would be less safe. Interestingly, if you fill in the rest of the two sine waves, you have a standard US 240V circuit. ;-)

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grandpa asked me a question regarding the signal coming out of a power>outlet. We know that the ground hole is always ground, and that between the0>two power holes there is a 120 Hz sine wave signal. However, I don't know how9>exactly is that signal sent. That is to say, what are the node voltages at0>the holes? Is one hole giving the whole range of voltages while the other

staggered9>half-rectified sine wave (figure 2)? Thanks in advance for any help..>u>Figure 1:

I don't understand your drawing, this one is closest. Assuming0everything is wired correctly and there are no faults in the system, you'reacorrect the "ground" pin (the round one) is grounded. ;-)d.The "neutral" pin (the left, larger, one, if looking at an outlet with the

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