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A few questions come to mind. If the main is grounded with it's own rod at the house and the neutral is not combined with the ground at the main, would it be considered a live conductor? If so, then it would also be isolated at the sub panel, correct? What's wrong with grounding the sub panel with it's own rod? Ground is ground right? Grounds and neutrals are a source of confusion here and other places. I have only one ground rod, BUT all my subs are within the structure, nothing is run underground. Thanks for your expertise. :vs_cool:
The neutral is ALWAYS a grounded conductor. Even if all grounds and neutrals in the main panel are landed on separate bars, the neutral bar is grounded with the bonding screw ONLY in the main panel. Neutral and ground should not cross anywhere else.

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it doesn't. that is in reference to the requirement of a grounding electrode for sub-panels placed in a building/structure separate from the MAIN, which of course is code.


Maybe you intended to say that in your statement?? "According to codes a sub-panel should have at least one ground rod of it's own"
 

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it doesn't. that is in reference to the requirement of a grounding electrode for sub-panels placed in a building/structure separate from the MAIN, which of course is code.


Maybe you intended to say that in your statement?? "According to codes a sub-panel should have at least one ground rod of it's own"
I don't understand the question then. Wouldn't the sub-panel in a separate garage have to be bonded to a ground rod there before it would pass inspection?
 

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Dem dere rules:
1) neutral and ground are common at ONLY one place - the main panel.
2) ground electrodes (rods) are required at the main panel, and any sub panel in a DETACHED structure.
3) sub panels within a structure with the main panel do not require a grounding electrode.
4) ground (Electrical grounding conductor, ECG), is not tied to neutral anywhere except in the main panel.
5)Neutral is never tied to ground except as above with one exception - in old 3 wire feed to a dryer, the neutral is also ground,; new construction requires a 4 wire feed.
6) The ground wire is not a current carrying wire - don't use it as such.
7) the ultimate decision lies with the AHJ - the authority having jurisdiction.
 

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where's my table saw?
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A few more questions ...

The OP has 6 wires in the conduit, as far as I can tell 4-#12's and a 2#14's. Can he twist pairs of the 12's together at the main, and wire to a appropriate size breaker to increase the current capacity, leaving the 14's for lighting and small power tools?

If not, can he pull 3 or 4 # 8's through the conduit using the last of the #12's as a puller? Can the one of the #12's be used as a ground if the other wires are larger?

Can the existing conduit serve as a internal guide to run a large one around it? That way the drive need not be torn up OR is there a depth rule for "new" construction? Is this new construction?

I'm glad I'm not the only one who is confused by all this. Great reasons not to ask woodworkers for electrical advice.... with certain exceptions.

Finally, it sounds like the OP will need a ground round for his sub panel because it is a detached structure? I hammered my 6 footer in with a sledge hammer, BUT I watched a You Tube where a small electric jack hammer just drove one into the ground with ease.
 

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The OP has 6 wires in the conduit, as far as I can tell 4-#12's and a 2#14's. Can he twist pairs of the 12's together at the main, and wire to a appropriate size breaker to increase the current capacity, leaving the 14's for lighting and small power tools?


No, for two reasons - it violates the one circuit rule, and the problem with paralleling two current carrying conductors is if one should break, the other is then capable of major overload. If a conductor in a single wire circuit breaks, it is simply no voltage.


If not, can he pull 3 or 4 # 8's through the conduit using the last of the #12's as a puller? Can the one of the #12's be used as a ground if the other wires are larger?

Can the existing conduit serve as a internal guide to run a large one around it? That way the drive need not be torn up OR is there a depth rule for "new" construction? Is this new construction?



Doubt this is doable - how would you pull the larger conduit?


I'm glad I'm not the only one who is confused by all this. Great reasons not to ask woodworkers for electrical advice.... with certain exceptions.

Finally, it sounds like the OP will need a ground round for his sub panel because it is a detached structure? I hammered my 6 footer in with a sledge hammer, BUT I watched a You Tube where a small electric jack hammer just drove one into the ground with ease.


Yes, ground rod is needed. Another way to drive it is with a hammer drill set in hammer only mode.
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Jack of too many trades..
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Discussion Starter · #70 ·
Driving an external ground isn't a big deal. My new place sit on top of a loess bluff, so I don't think that I'll hit rocks near the surface. That said, both my old house (and this new old one) don't have a grounding rod. Instead, the main panel is grounded to the plumbing. I've read that grounding the electricity to the plumbing leads to micro-holes in the copper, and should be avoided.



Regardless, it sounds like the garage will need it's own grounding point. I'll pick one up also. It's better to do too much than not enough. It's too bad copper got so expensive over the last 10 years, but I can cope if I spread out the costs.
 

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where's my table saw?
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while we are "grounded" ....

The ground connection in the main panel would normally go to the ground rod in the ground? This is where all the green colored wires are mounted on the grounding bar as well as all the bare copper wires in the Romex and the aluminum shied which is twisted around the conductors go? The white wires go to the neutral bar and are secured by screws in the bar? In the main panel, the neutral bar is connected to the ground via a screw? The panel cabinet itself is then grounded as well? Further, any EMT that is connected to the panel and metal outlet boxes is also grounded?

In this case we have a 3 conductor with a bare copper ground:


Here's what I'm used to seeing for an aluminum wire supply to a sub panel, probably 200 AMPs:



Here's the main and the sub wired up. Notice all the slots in the main panel, but there are no breakers in the sub yet. The sub is fed using a 100 AMP breaker in the main. I don't see a disconnect breaker in the sub, which if in a detached location would be required?

 

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The boxes are side by side. The breaker feeding the sub-panel would be the disconnect. What is missing is the ground wire from the main to the sub-panel.
 

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The boxes are side by side. The breaker feeding the sub-panel would be the disconnect. What is missing is the ground wire from the main to the sub-panel.
It's there...I had to look twice....curled in at the top of ground bar.


I hate wiring/searching in a box like on the left.....HEADACHE !!!! I've been told mine is neat BUT I've seen some of the older electricians that were artists with their wire....FINE ART at that!!! YES I did take pics of some for inspiration!!!
 
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where's my table saw?
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I saw the breaker

I also see a wire loop at the top of the sub on the left that looks like its connected to the ground bar. This is a photo I grabbed off the net,
and the sub is grounded according to the text:
https://www.wiringdoneright.com/subpanel/
 

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The ground connection in the main panel would normally go to the ground rod in the ground?
YES

This is where all the green colored wires are mounted on the grounding bar as well as all the bare copper wires in the Romex and the aluminum shied which is twisted around the conductors go? The white wires go to the neutral bar and are secured by screws in the bar?

In a main panel, the usual approach is to land all neutrals and grounds on the same neutral bar. Most don't have a separate ground bar. The only drawback is that if it is ever desired to make the main panel a sub panel in the future, the ground bar has to be installed, the neutral bonding has to be removed, and all the ground wires transferred to the new ground bar.




In the main panel, the neutral bar is connected to the ground via a screw? The panel cabinet itself is then grounded as well? Further, any EMT that is connected to the panel and metal outlet boxes is also grounded?

Yes, to both questions, though common thought is to run a ground wire in the conduit because of the possibility of damage or corrosion, etc, causing a disconnect in the conduit (electrically). Code does not require the ground wire.

In this case we have a 3 conductor with a bare copper ground:


Here's what I'm used to seeing for an aluminum wire supply to a sub panel, probably 200 AMPs:



Here's the main and the sub wired up. Notice all the slots in the main panel, but there are no breakers in the sub yet. The sub is fed using a 100 AMP breaker in the main. I don't see a disconnect breaker in the sub, which if in a detached location would be required?

A disconnect is required in a sub panel when the number of breakers exceed 6.

It's there...I had to look twice....curled in at the top of ground bar.


I hate wiring/searching in a box like on the left.....HEADACHE !!!! I've been told mine is neat BUT I've seen some of the older electricians that were artists with their wire....FINE ART at that!!! YES I did take pics of some for inspiration!!!
Two schools of thought - those work of art wired panels do make it easy to trace wiring. On the other hand, many boxes are wired with an extra loop in the wire. This is done in case of having to move breaker locations in the future. One thing that helps in that situation - all breakers are labeled, and the associated wire is labeled right at the clamp (assuming romex). Easily done with a permanent marker on the wire.
 

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where's my table saw?
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When I wired my shop panel ....

Rather than label each circuit with a "name" I chose to use a color code system. The colored electrical tape appears on the breaker that corresponds to the tape on the outlets. Sometimes only one color was needed, for example, blue. In other cases I ran out of colors so I used 2 colors, like orange and white. I cut the tape into small pieces and placed them on the appropriate breakers.(sorry no photos of the panel)
 

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Jack of too many trades..
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Discussion Starter · #77 ·
My father-in-Law taught me to do residential wiring and he insisted that one should always put a loop in the wire, precisely to move breakers. It saved me a lot of trouble on several occasions...


Also, here's a link I found valuable...

https://www.constructionmonkey.com/calculations/electrical/tables/wireconduit


This confirmed that I can fit x4 #6 wires into my existing conduit and that 60 amps is my limit under the circumstances.


Also... that 60 amp, six slot panel that _Ogre originally posted a photo of, was on clearance for $13 at Lowes, so I picked up the last one. Obviously, it's not good for a long term solution, but I don't think I'll be putting in more than four independent circuits with a 60 amp service.
 

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When I drive in a ground rod I use a T-post driver. Goes pretty quickly.

It doesn't work very good 50 miles north of you, we have Houston Black clay for the first 6-8 feet then it changes to yellow clay, that chit is like granite, when I got my hydef plasma cutter they insisted I had a ground rod 10 feet in the ground, at first I figured I could just shove it in the ground with the front end loader, it bent before I could stop the bucket, so I got another grounding rod and was going to use the post driver to drive it, I got it to about 7 feet, and it stopped.


When they were installing the table they said it had to be 10 ft so I handed the kid a 20 lb sledge, he and his partner wailed on it for about 15-20 minutes and decided that 8 feet was enough
 

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It doesn't work very good 50 miles north of you, we have Houston Black clay for the first 6-8 feet then it changes to yellow clay, that chit is like granite, when I got my hydef plasma cutter they insisted I had a ground rod 10 feet in the ground, at first I figured I could just shove it in the ground with the front end loader, it bent before I could stop the bucket, so I got another grounding rod and was going to use the post driver to drive it, I got it to about 7 feet, and it stopped.


When they were installing the table they said it had to be 10 ft so I handed the kid a 20 lb sledge, he and his partner wailed on it for about 15-20 minutes and decided that 8 feet was enough
In Garland, TX the bedrock in a lot of areas is only about 2' down. They must have to run the ground rods sideways. At my house it's clay with a foot or two of sugar sand on top.
 

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i think you'd be a lot happier with a bigger panel. 2 slots will be for your main, 2 for the 240 table saw, that leaves 2 slots for everything else 120 volts. it may work fine but you'll never be able to add a compressor circuit or dust collector
 
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