120VAC Ground

[trem]

Did not know where else to ask this.
My "shop" is a 10x12 shed in my backyard.
It is 15 feet from the outside 120 outlet on the back of my house.
I installed a surface mount outlet in my shed, hardwired that to a 25 foot 12 AWG (i cut That End off the cord) extension cord, and i plug the other end of the cord into my outside outlet on the back of my house.
Come to find, the House Outlet is not grounded. I replaced the 30 year old receptacle, checked the ground wire...it is not broken, but it reads open to ground.
I ran a short Ext Cord from inside my house, so i could use a DMM to check this outlet.
Neutral = Short to ground
Ground = Open to ground
I opened some of the inside (of the house) outlets that this plug shares a breaker with, to see if i could find where it ties to.....i cannot find it.
Would it be Kosher to drive a ground rod into the earth right at my shed, and ground the shed outlet to That Ground Rod, while still using that un-grounded outlet on, the exterior of my house, for 120 power.?
Thank You

[WesG]

Exactly how are you determining that neutral is shorted to ground, and that the ground wire reads open to ground? You should not be using an ohm meter on a live circuit.

FWIW - the neutral and ground wires are bonded inside the breaker panel (and only one panel if you have many) - and NO WHERE ELSE. If you find that neutral and ground are connected together inside your outlet (or an upstream outlet), this is called a bootleg ground and is prohibited under the NEC for good reason.

You should be able to use a voltmeter between hot and ground to read a number which is very similar, but almost never the same as, the number between neutral and hot. You might be able to read a few volts between neutral and ground. This number should change based on whether or not there are other appliances in use on that branch circuit.

Wes

[WesG]

PS - I am not an electrician, but the kosher way to do this around here is to run underground wiring through conduit (or buried deep with direct-burial-rated wire) from your main panel to a sub panel in the shed. Use wire big enough to handle the load from all the circuit breakers in the panel. I don't know if you can drive another ground rod or not, but you definitely cannot use only that ground rod as your safety ground, nor can you bond ground to neutral in your pony panel.

You could also do aerial wiring, but I'm not at all familiar with the codes for that stuff.

[SoulFetish]

Did not know where else to ask this.
My "shop" is a 10x12 shed in my backyard.
It is 15 feet from the outside 120 outlet on the back of my house.
I installed a surface mount outlet in my shed, hardwired that to a 25 foot 12 AWG (i cut That End off the cord) extension cord, and i plug the other end of the cord into my outside outlet on the back of my house.
Come to find, the House Outlet is not grounded. I replaced the 30 year old receptacle, checked the ground wire...it is not broken, but it reads open to ground.
I ran a short Ext Cord from inside my house, so i could use a DMM to check this outlet.
Neutral = Short to ground
Ground = Open to ground
I opened some of the inside (of the house) outlets that this plug shares a breaker with, to see if i could find where it ties to.....i cannot find it.
Would it be Kosher to drive a ground rod into the earth right at my shed, and ground the shed outlet to That Ground Rod, while still using that un-grounded outlet on, the exterior of my house, for 120 power.?
Thank You

NO!!! DON'T DO THAT!
I'll explain why later When I can if someone already hasn't

[trem]

Exactly how are you determining that neutral is shorted to ground, and that the ground wire reads open to ground? You should not be using an ohm meter on a live circuit.

Shouldn't any Neutral read a short to Ground.?
How am i determining.?
Like i said.....
"I ran a short Ext Cord from inside my house, so i could use a DMM to check this outside outlet."
Neutral = Short to ground
Ground = Open to ground
Maybe i do not understand what you are asking.?

Plug in Detector lights up.....
"Ground Fault"
Thank You

[eschertron]

Yes, the ground should read short to ground. Where exactly did you determine 'ground' when you read neutral to ground? If the ground pin is floating (sounds like it) then there's no electrical ground to reference your neutral line to. Are you using the metal case/conduit at the outlet?
In any event, neutral and the ground pin should read approximately zero Ohms, assuming neutral and the ground wire are bonded together in the main panel. I replaced a 70+ Y.O. fuse box in my house, adding a bunch of 3-wire circuits where there were none. The learning curve's not steep. The 'ground fault' detector tells you what you already know; there's no connection to the ground pin in the outlet.

[trem]

Again, maybe i do not understand what you guys are asking, but..... Where did i determine ground.?
......."I ran an extension cord, from a Good Outlet, Inside the house, to the outside, near enough this "bad"outlet, so i could use my DMM."
Those two outlets:
Neutral to Ground = Short
Ground to Ground = Open

At any rate, i found the problem. There is a J-Box under the house. Hard to tell 30 years later, but it looks like this outlet might Not Have Ever been grounded.
It is now.
Thanks

[catalin gramada]

tied working null with protection null together is a stupid sloppy electrical practice. I found the same arangement in a friend house and sometimes get shocks from his fridge.

[Leo_Gnardo]

At any rate, i found the problem. There is a J-Box under the house. Hard to tell 30 years later, but it looks like this outlet might Not Have Ever been grounded.
It is now.
Thanks

"This outlet" being the one you plug your shop power into? Did you find there IS a ground stake for the house, and neutral bonded to it in the main breaker box?

Certainly there's lots of older houses (like mine) that have new breaker boxes, properly wired to ground. BUT all the branch circuits have no 3rd wire for a proper ground. Of course the proper and expensive thing to do, is install all new branch circuit wiring to all outlets, a couple thousand dollar job. A practical but not code endorsed cheat, if you have BX, use the steel shield as ground. In your case it might be a good idea to make a special "home run" to your workshop right from the main breaker box. Imagine what happens when the steel corrodes, that's why it isn't code. Costs a little $$$ to put in a "home run" for your shop but it's your shock & fire safety at risk.

Second ground stake may set up a ground loop. Which is no big deal most days, but if you have a lightning strike it could make matters worse. The question's been kicked around a lot over at Audio Asylum, "should I put in a separate ground stake for my listening room / studio?"

[SoulFetish]

At any rate, i found the problem. There is a J-Box under the house. Hard to tell 30 years later, but it looks like this outlet might Not Have Ever been grounded.
It is now.
Thanks

When you say " it is now " it scares the shit out of me. Look, please don't mess with the mains wiring in your house unless you are a qualified and a licensed electrician. Especially in a location where you plan on working with electronic equipment. If you can't afford to hire someone who is a professional, Maybe you can find a qualified electrician as a friend or family member who may be willing to come and work with you. I'm willing to bet every time and electrical system is built that resulted in a tragic injury or fatality, The work was done by somebody who either thought they knew what they were doing, or. Didn't care

[eschertron]

Again, maybe i do not understand what you guys are asking, but..... Where did i determine ground.?
......."I ran an extension cord, from a Good Outlet, Inside the house, to the outside, near enough this "bad"outlet, so i could use my DMM."
Those two outlets:
Neutral to Ground = Short
Ground to Ground = Open

At any rate, i found the problem. There is a J-Box under the house. Hard to tell 30 years later, but it looks like this outlet might Not Have Ever been grounded.
It is now.
Thanks

My confusion was that you had two extension cords going, one for service, one for testing. Thanks for clarifying that. While I'm not as alarmed at DIY wiring as others (and perhaps I should be) I question how you determined that the test outlet or the fix you made for the junction box are referenced to 'the one true ground'. Have you inspected the mains panel for a neutral/ground bond, and are there three wires going from that panel to each outlet and junction box? While you're in it, might as well verify it (or fix it) to be correct. A lot of houses (that I've lived in, and I'm sure others) were not built to code, or at least to today's code. You have the tools to check and make it right.

[trem]

When you say " it is now " it scares the shit out of me. Look, please don't mess with the mains wiring in your house unless you are a qualified and a licensed electrician. Especially in a location where you plan on working with electronic equipment. If you can't afford to hire someone who is a professional, Maybe you can find a qualified electrician as a friend or family member who may be willing to come and work with you. I'm willing to bet every time and electrical system is built that resulted in a tragic injury or fatality, The work was done by somebody who either thought they knew what they were doing, or. Didn't care

Either i have written The Worlds worst post or.......
Am i really "messing with" the mains.?
There is a J-Box, with a metal cover, under my house, and That Feeds this outside receptacle. I was thinking i would find That Scenario inside a receptacle box inside my house. But i did not, it is a box all by itself, under the house.
Anyway I checked out this J-Box, and the ground wire was out of the twist lock/splice cap. Did it fall out, or maybe it was Never Terminated.?
I do not know.
I connected that J-Box to its ground and now all is OK.
Is this situation really all that scary.?

Leo Gnardo-
Yes...later this year i hope to have enough money to have an electrician, maybe run some conduit under the ground and hard-wire my shed. Maybe he can turn this outside outlet into a J-Box and run the conduit from there.?
This current setup is (hopefully) somewhat temporary.
Thank You

[Chuck H]

I don't have a confident contribution here, but I just want to say that other than understanding something about what makes a short, and is therefor bad, I've been stymied by what should be an electricians work on more than one occasion. For years I thought that having a decent understanding of electronics must be on par or even exceed what would be needed for plain 'ol house wiring. Not so. And I don't mess with this stuff unless I'm sure of what I'm doing. I'm more than a little relieved that I'm not the only one

[SoulFetish]

Either i have written The Worlds worst post or.......
Am i really "messing with" the mains.?
There is a J-Box, with a metal cover, under my house, and That Feeds this outside receptacle. I was thinking i would find That Scenario inside a receptacle box inside my house. But i did not, it is a box all by itself, under the house.
Anyway I checked out this J-Box, and the ground wire was out of the twist lock/splice cap. Did it fall out, or maybe it was Never Terminated.?
I do not know.
I connected that J-Box to its ground and now all is OK.
Is this situation really all that scary.?
Thank You

Trem, I'm not trying to be a dick, or come across like I think you must wear a helmet and a bib when you go out.
I'm sorry if it came across that way. I just don't want to see you, or anyone else get hurt. All I'm saying is that it is very easy for intelligent people to come to logical conclusions, which are completely false, based on the information they have at the time. I've done it, if anyone's made it past the age of 20 (maybe even 30 ), I'm sure there are moments you look back on and think "Holy Shit, I can't believe I'm still alive!!".
Maybe I overreacted. Reconnecting the earth to a junction box seems benign enough if the wire is there anyway. But, if you don't have any experience wiring 2-phase residential, there is wisdom in having someone with you who knows more than you. Because at the very least it's your life and your ass on the line once you do anything with that wire.

[trem]

No Prob-blem-o.....
I can completely relate to what you (and Chuck) are saying. My Slight Knowledge of electronics is 100x bigger than my knowledge of Residential Wiring. Though, the exception would be the troglodytes that:
Wired
Painted
Flooring
HVAC
etc etc
in my house. These guys must have been your typical Speed-Freak, Tract House, So and So's.
I was in the painters union for 25 years in San Francisco. I met LOTS of capable electricians working downtown. I doubt any of them made it out to our pile of crap project.
Hoffman Builders (the A-Holes that build our homes) had a field office out by me for several years. They eventually had to close it down because it kept getting Torched/Vandalized. I do not trust anybody that was hired by Hoffman Builders.
Anyway...i understand where you guys are coming from. It seems like we are just connecting extension cords inside a wall. I only have to turn this outside outlet into a J-Box and run 3 wires for 20 feet...just exactly what this extension cord is doing now.
You could say the same thing about installing a 3 wire power cord in an old amp. Look at all the funky scenarios a first time guitar player could get into with That Situation.
I would love to save the money, but when it comes time, i will just get hold of an electrician that a few of my neighbors have used, and make sure it is all OK.
If i can continue to make a Mountain out of a Mole Hill.......I have had a Bunch Of Surgeries on my Back, knees, wrist. I have a fused right wrist and a fused lower back. So i have seen LOTS Of Surgeons. I asked a few of them about ..."How hard is it to be a Anesthesiologist".?
The consensus was, you can teach a decent physician to be a decent Anasth. BUT, if something "Goes Wrong" during the operation, THAT is where you want the Guy/Gal that graduated at the top of their class...if you know what i mean. You never know when a simple job might turn into a difficult one.
With that said, i understand all the Warnings/Questions. You guys are 100% correct. Mains power is nowhere for an amateur. I would hate to be working on an amp and get zapped because of something stupid that i did, and should not have done to begin with.
Thanks Again.....appropriate all your expertise.