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[Runner]

I used to water ski in the Delaware river, from Bristol down to Philadelphia, and while I don't want to even think about what might have been in that water, it probably wasn't worse than the Jersey shore water where I did the rest of my skiing.

Thread drifting down the river....

Waterskiing on the MO river 1994 with KC skyline in background. Good times. Always keep your mouth shut when you dive in or fall....

 

[Gord Baker]

Good morning, I can’t seem to find anyone that can give me a clear answer.
The video below is as close as I have come.
The question is: if the neutral ( in most cases white ) is connected to the same bus bar as the grounds and the neutral is what carries the electricity back to the source ( which is maybe a different topic ) than why are the grounds not energized within the panel ( including but not limited to the exposed ground that I’ve placed on the exterior of my wall to ground the system)
Thank you and I hope that you all have/had someone special to spend your holiday with.
Good video here

In Ontario the Grounds and Neutral have separate buss bars. Seems logical.

 

[chim]

Mostly good info already. A few thoughts from a retired electrichicken:

The neutral and ground are bonded together at the first switch / breaker only. At that point both are also common with the Neutral from the utility, water piping, building steel and any metallic item that can become energized during a fault.

The feed to a subpanel needs to have separate conductors for the neutral and the ground and have separate bars for each.

The ground is not intended to carry current except during a failure / fault, and is only sized large enough to cause a breaker to trip or a fuse to open.

The math is different for Wye and Delta systems. In a delta system the phase to phase voltage is the coil voltage, and the line current is 1.73X the coil current. In a Wye system the phase to phase voltage is 1.73X the coil voltage and the line current is the coil current.

On a Delta system the phase to phase voltage is 2X the low voltage (on TWO of the phases) because one of the transformers has a center tap. Half way between the ends of a 240v coil is 120V. The voltage from the third phase (aka High Leg) to Neutral is over 200V. Instead of half a coil between the neutral and "hot" there are 1-1/2 coils. Although coil / phase to phase voltage is 240V, the High Leg voltage isn't equal to 1.5 times the coil voltage because the voltage in the coils is out of phase (sync) with each other. This configuration has fallen from favor, especially in non-industrial applications. In industry much of the load is 3Ø and 120V loads are minimal.

On a Wye system the voltage from each of the three phases to neutral is 120V and the phase to phase voltage is 208V (1.73X 120V). This system is more widely used for non-industrial applications because every pole in the panel can be utilized and the loads can be balanced better.

 

[MTgreg]

Good morning, I can’t seem to find anyone that can give me a clear answer.
The video below is as close as I have come.
The question is: if the neutral ( in most cases white ) is connected to the same bus bar as the grounds and the neutral is what carries the electricity back to the source ( which is maybe a different topic ) than why are the grounds not energized within the panel ( including but not limited to the exposed ground that I’ve placed on the exterior of my wall to ground the system)
Thank you and I hope that you all have/had someone special to spend your holiday with.
Good video here

Here's how I explain it to my clients:

 

[Mike1955]

Also don’t forget that the ground buss and neutral buss are separated in a sub panel.

Beaver Cove. This state is true, in some areas. In some states the neutral is isolated, from the ground

 

[ultrarunner]

Watched old time licensed electrician decades ago test for live conductors by touching…

He said that was how he was taught and I found it shocking.

I’m guessing he was born around 1900…

Was this a one off or a common practice years ago?

Also, I saw a new home being wired many years ago and the ground was a thin bare copper run independently from box to box under the drywall with the copper being wrapped under a nail head holding the box to the stud.

If you needed a ground it was by pigtail to the metal box.

 

[MT Kioti]

First, don’t ever rely on electrical advice found on most online forums like YouTube or even here. Go to a reputable source like MikeHolt.com, which is designed for electricians, but you will be able to find what you need there.

Now, look at your electrical system and pretend (for a minute) it is 12 volt DC, just like your car. Your transformer (generally a green box out in the yard or the round cylindrical ones on a pole) is two 12 volt batteries, connected in series. The one thing that makes this work is that the cable between the two batteries is connected to a ground rod driven directly into the earth. One side has 12 volts from the battery + terminal to the ground rod, and the other side has 12 volts from the battery - to the ground rod, and yet you still have 24 volts between the outside terminals of the two batteries. Now connect the neutral to the ground rod and nothing changes. Your voltages are still the same.

This example has brought clarity to many people about how our split-phase system of power works in USA, Canada and many other countries.

If you really want to get nervous, keep doing a bit of research (the MikeHolt site is a good place) about stray electrical current and bodies of water, and you will never go near a swimming pool or marina again.

 

[WinterDeere]

Go to a reputable source like MikeHolt.com, which is designed for electricians, but you will be able to find what you need there.

I'm a member at the MikeHolt.com forum, but unless you're an electrician or electrical engineer, your posts will be removed and your account will be blocked. It is a forum for industry professionals only, not homeowners, and they enforce that quite rigorously these days.

There has been a lot of good information posted on this thread, very notably @chim's last post. Unlike many internet forum threads on electrical / NEC issues, there has not been much bad information on this thread.

That said, I'm an EE, not an electrician. I'm strong on theory, but most competent commercial electricians will know the code book better than me.

 

[Snezzy]

While we are talking about grounds and neutrals we ought to be aware of a hazard known as a floating neutral. If you ever see the lights get brighter, not dimmer, when a heavy load such as a compressor starts up, it's possible you have a floating neutral. That would be a failure of the neutral line between your house and the step-down transformer. Your 240-volt supply from the transformer would be split at something like 140 vs 100 instead of 120 and 120, depending on the particular division of the load at your house onto the two legs.

Any safety issues here? Absolutely! Normally if the primary side of the transformer, perhaps 7200 volts, were to short to the secondary--which is supposed to be no more than 240 volts separated into 120 and 120--you could see 7200 volts right there in your house. That might happen in a windstorm or if a car knocked down a utility pole. The proper connection and grounding of the neutral ensures that you won't see 7200 in your house.

What to do? Call the utility's emergency number and report a floating neutral. If they're any good they'll be at your place before you can think about hanging up the phone.

 

[Dennis Mohn]

I'm a member at the MikeHolt.com forum, but unless you're an electrician or electrical engineer, your posts will be removed and your account will be blocked. It is a forum for industry professionals only, not homeowners, and they enforce that quite rigorously these days.

There has been a lot of good information posted on this thread, very notably @chim's last post. Unlike many internet forum threads on electrical / NEC issues, there has not been much bad information on this thread.

That said, I'm an EE, not an electrician. I'm strong on theory, but most competent commercial electricians will know the code book better than me.

Agreed, and thank you for not trying to explain the theory of holes.