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chiefengineer
Jun 26, 2008, 11:13 AM
SCENARIO:
A guest was leaving after visiting our pool.
He claimed to have "gotten a little jolt" from my mudroom
lightswitch. The next day I could not replicate the shock
on myself... perhaps he was wet (?)... so I perfromed a series
of tests with my digital multimeter. I recorded the results
on a single piece of paper (scan attached: test1.jpg).

BACKGROUND:
The switch is part of a 5-yr. old addition built by a
bankrupted contractor as new construction that I bought 4
years ago. Most wiring is now completely inaccessible to inspection.

TESTING:
What I know from the 16 possible combinations of switch positions:
1)Two double switches control three lights: 1 and 2 (garage), 3 and 4 (mudroom).
2)Switches 1 and 3 control a breezeway light "in between" them,
except that both have to be "on" to make the light come on.
3)Switches 2 and 4 control other lights each... they work fine.
4)1,2, and 3 are controlled by a newer single breaker in the garage;
4 is controlled by a 20-yr. old breaker in the house.
5)It would appear hot leaks at 120V to ground on the switch cover screws of 3
ONLY under the following conditions: "1-off/3-off", "1-off/3-on"; 3 also
leaks a hot ground at about .2V ONLY with "1-on/3-off".
6)The voltage climbs slowly between the screw and ground... for instance, if I
touch the probe and kneel with bare skin on the cement (I wore rubber shoes)
it climbs quickly to 60V+ (although I felt no shock).
7)I cannot verify that any of the six breaker boxes on the property are
grounded, but my home inspector tested everything with a GFCI tester
so I think that probably would've been discovered. I simply can't find
any grounding rods anywhere except one attached directly to my pool pump
far away from any of this, the water pipes are all PVC, and I'm not originally
from far south Texas (they seem to have their own method of doing things).

CONCLUSIONS:
The connections to the breakers are all sound... no rubbing/touching/crossing.
The wiring in the garage attic to this area contains a lot of splicing/dicing
I would not have done outside of junction boxes... on the other hand the caps
are tight and there are no missing connections.
My solution so far has been to remove the screws on three... it is a double
switch plate held on by the screws to 4. I can find no bad wiring in the breezeway
light or anyplace hot or neutral touch ground where I can get at this wiring in its
20 ft. enclosed breezeway. This could be totally harmless after 5 years (I could put
in some plastic screws), but since I can't verify anything I am more
inclined to cap off the wires in switches
1 and 3 and leave the breezeway light without function in case there is a
hot bare ground touching wood somewhere (seems to me this would only flip
a GFCI breaker which this is not). On the other hand
I may be overlooking a bigger problem such as no master ground to the breaker box.
I get no readings from the grounds at the 1 and 2 switch, but
I can get continuity BETWEEN the screws on 3 and 4 which are on totally
different circuits, and since 4 is probably grounded correctly it leads me to
conclude a ground is loose/rubbing up in the breezeway where I can't get.
I'm guessing my guest was wet and well grounded, or simply bridged the 3/4
screws with fingers and is lucky to have discovered
this as only a brief grope for lighting. I have wired and re-wired many many things in my
life, but there are a lot of variables here and any addition to these ideas would be greatly appreciated... like maybe the switch itself is shorting??

KISS
Jun 26, 2008, 12:41 PM
Since you have a pool, that creates lots of problems. I's might initially assume that nothing is wrong, however I would d the following:

1. Replace switchplate with a plastic one. Decora style switches might be an option. Really concerned replace the metal screws with nylon.

2. Power circuit from a GFCI breaker.

Now to address the ground problem.

1. Is there a separate neutral and ground bus in your main panel. If so, the ground may be at the transformer or at the meter disconnect, if you have one.

2. There has to be a ground somewhere.

1. Outside disconnect (ground an neutral will be separate)
2. Main panel (ground and neutral will be separate)
3. At transformer
3a. Ground and neutral may or may not be separate

Usually there is a ground at the transformer and the house. The pool should have it's own rod because it is detached.

Ground can be a water pipe, but you ruled that out.

chiefengineer
Jun 26, 2008, 09:36 PM
First, thank-you for the response. It is appreciated. The bold is NOT shouting,
But just highlighting my answers...



Since you have a pool, that creates lots of problems. I's might initially assume that nothing is wrong, however I would d the following:

THE POOL IS ON ITS OWN BOX AND METER AND SEPARATE FROM THIS. I MENTIONED
IT AS AN EXAMPLE OF WHAT I DON'T SEE. THERE IS NO TRANSFORMER GROUND. THE METER ON THE HOUSE IS IN SERIES WITH THE MAIN (ONLY) TRANSFORMER, AND THE ONLY GROUND I CAN GUESS AT IS COMING BACK INSIDE THE PANEL TO THE METER...BUT I can't OPEN THE METER TO SEE IF IF IT REALLY GOES INTO THE PVC PIPE TO THE GROUND.

1. Replace switchplate with a plastic one. Decora style switches might be an option. Really concerned replace the metal screws with nylon.

SWITCHPLATE IS PLASTIC ALREADY, CURRENT IS FROM SCREWS ONLY. WILL LOOK FOR NYLON.

2. Power circuit from a GFCI breaker.

I COULD BUY ONE FOR THE WHOLE GARAGE, BUT IT SEEMS CERTAIN IT WILL TRIP
IF GROUND IS ALREADY HOT (WHAT AM I MISSING?).

Now to address the ground problem.

1. Is there a separate neutral and ground bus in your main panel. If so, the ground may be at the transformer or at the meter disconnect, if you have one.

YES, IN FACT THEY ARE SEPARATE IN THE GARAGE MAIN PANEL AND 220V BREAKER GROUND WIRES ARE ON BOTH NEUTRAL AND GROUND BARS...BUT FROM WHAT I READ IF THERE IS A MAIN DISCONNECT IN THE PANEL (WHICH THIS GARAGE PANEL HAS) THEY ARE MARRIED AND THIS IS IRRELEVANT (PLEASE DISPUTE...I THOUGHT THIS WAS WRONG AT FIRST).

2. There has to be a ground somewhere.

AGREED. BUT IN MY MUDROOM WHY DOES IT SEEM TO BE FEET?

1. Outside disconnect (ground an neutral will be separate)

IT WOULD APPEAR THIS PANEL IS SECONDARY TO THE MAIN HOUSE PANEL WHICH FEEDS BOTH THE INSIDE HOUSE PANEL AND THE GARAGE PANEL.
NEITHER HOUSE PANEL HAS A MAIN DISCONNECT, BUT THE 200A PANEL IN
THE GARAGE DOES.

2. Main panel (ground and neutral will be separate)

THEY ARE SEPARATE IN THE GARAGE PANEL AND MIXED WITH 220V GROUND WIRES
ON THE NEUTRAL AND GROUND BAR WHILE THE 120V ARE ON THE GROUND BAR ONLY...BUT THE MAIN
DISCONNECT IN THIS PANEL IS SUPPOSED TO MAKE THIS NULL (?).

3. At transformer

I SEE NO GROUND THERE...WAS HIT BY LIGHTNING LAST YEAR WITHOUT ANY RAIN
WHILE I WEEDWHACKED A FEW FEET AWAY...LIKE A BOMB...THEY RESET IT AND REPLACED SOMETHING SMALL THAT TOOK THE CHARGE...NEVER SAW A DOG MOVE SO FAST IN MY LIFE.

3a. Ground and neutral may or may not be separate

RIGHT...DO I POWER UP THE PANEL WITH THE COVER OFF AND START FINDING OUT?
IS IT POSSIBLE THE BARS ARE NOT CONNECTED? WHY WOULD THE BREEZEWAY LIGHT ONLY LIGHT WITH BOTH SWITCHES ON INSTEAD OF EITHER?

Usually there is a ground at the transformer and the house. The pool should have it's own rod because it is detached.

I'M GUESSING THE GROUND AT THE POOL IS FROM A WIRE INSIDE THE POWER CORD TO
THE SPA HEATER OR PUMP...AND THAT EFFECTUALLY DOES THE WHOLE PANEL (?).

THE WATER PIPE ENTERING THE GROUND IS PVC.

Ground can be a water pipe, but you ruled that out.

KISS
Jun 27, 2008, 01:57 AM
2. Main panel (ground and neutral will be separate)

THEY ARE SEPARATE IN THE GARAGE PANEL AND MIXED WITH 220V GROUND WIRES
ON THE NEUTRAL AND GROUND BAR WHILE THE 120V ARE ON THE GROUND BAR ONLY... BUT THE MAIN
DISCONNECT IN THIS PANEL IS SUPPOSED TO MAKE THIS NULL (?).


This is the one I picked to deal with. I'm either having trouble understanding or there is something wrong.

Let's go with the NORMAL case of ground and neutral are the same bus bar in the main panel and ground and neutral should be separate in the garage panel. If the garage is detached, then there should be a ground rod at the garage.

1. If the main panel is connected to a ground rod, then there should be a single large wire that seems to be out of place. Probably the largest bare wire. Similarly for the garage panel.

2. How about uploading a photo using "Go advanced" for the garage panel.

3. In the garage panel, only bare wires should be connected to the ground bus. Only white wires should be connected to the neutral bus.

For 240 ckts, white of a wht/blk cable can be connected to a 240 breaker.

For 240 ckts, red/black of a wht/blk/red cable will be connected to a 240 breaker and white to the neutral bar.

For 120 ckts, blk will be connected to the breaker and white to the neutral bar.

THERE SHOULD BE NO WHITES ON THE GROUND BAR. Bares only on the ground bar.

The garage panel may or may not contain a main disconnect.

BONDING SCREW

Look in the garage panel for instructions for a bonding screw on the neutral bar. It should not be in place. The screw is likely green.

KISS
Jun 27, 2008, 02:00 AM
Here is a source for Nylon screws:

Nylon Fasteners | Nylon Screws | Flat Head 82 degree Nylon 6/6 Machine Screws.Molded Nylon 6/6 Machine Screws offer excellant insulation in electrical and electronic appliactions. Lightweight and resistant to vibration and abrasions, nylon is nonmagn (http://www.smallparts.com/products/descriptions/mn-f.cfm)

Stratmando
Jun 27, 2008, 06:43 AM
In your drawing, you say both switches have to be on, I'm hoping you mean a 3 way(with 2 travellers) Shown it looks like neutral is gotten from 1 switch, and hot from the other switch. I would locate the problem of the shocks. Be sure the Neutral handles the load and the ground is intact between all boxes and fixtures. If something is shorted or leaking to something not grounded, it can become live.

chiefengineer
Jun 27, 2008, 10:46 AM
First, thank everyone very muchfor their input(s)!

1)House panel has no main cutoff and 100A breaker to the garage panel.

There are no visible rods near the house or the garage, and no bare wires
On the way anywhere except on the transformer where one runs down the
Pole and into the dirt (not a rod or block). With binoculars I think I
Saw a second ground from the transformer to a support cable. This unit
Took a direct lightning strike and nothing of mine got hurt. The house
And garage are attached by a breezeway.

2)Panel pic attached (garagepanel.jpg). Yes, there appear to be extension
Cords and romex both. (3) 220V third wires on the left side (all bare) go
To the neutral bar. Some of them are long and I can't be 100% that
One of them doesn't get very close to the panel cover when on. There is
Also some wiring attached to nothing in this panel, such as for future
Connections and even a generator hook-ups that dangle bare.


3)220V is installed much as you described except for one thing.
On the right side of the panel there is one 110V and one 220V breaker
And for some reason the third bare wire of the 220V goes to the ground block
On that side instead of neutral (something I would have not thought about doing). 110V's all use breaker/neutral/ground on each side.
I do not see a bonding screw (neutral and ground appear to be isolated
From each other except for the 220V on the right side using ground instead
Of neutral... that is also where the breezeway breaker is grounded? ).

Yes, it would certainly appear we have a hot/neutral situation in the breezeway.
Could this be coming from the panel because ground has "gone neutral" on
The grounding block on the right side, or a bare neutral 220V third wire is
Touching the panel cover on the left? The switches on each end of the breezeway
Are simple 2-way switches wired normally with grounds which shock on
One end with switches off.

KISS
Jun 27, 2008, 11:23 AM
1. No disconnect. How did that happen? Is there a separate box below the meter? This is where the disconnect can be.

You probably won't see a rod, only a wire going into the ground. The rod and connection is buried.

3. You have some work to do:

a) move all bares to ground bars.
b) ideally, there should be no sheathed cables in the box. They should only be wires after they enter the box.
c) Check presence of stray voltages after changes made.

You did not mention, if this panel is in a detached garage?

KISS
Jun 27, 2008, 02:06 PM
On the garage panel pic, on the top of the left ground bar, there is a very large lug. This would typically be the place that the panel ground is connected.

When you get bored, post a picture of your main panel.

If the outside of your house near the meter schematically looks like this: http://www.ecmweb.com/mag/708ecmCBfig1.jpg then, the main box would not necessarily have a main breaker. Ground would be done in the disconnect AND the main panel would be wired like the sub-panel.

Do you have an outdoor disconnect?

Stratmando
Jun 27, 2008, 05:24 PM
As Kiss Mentioned, the Ground is missing from ground lug to Meter connection. At that point you should have a ground rod, Connecting to Meter Can Neutral, Your disconnect is your Main Breaker. Many Places require a Disconnect at Meter Can. With that you could work on your Panel with power switched off. Also like Kiss mentioned, remove sheath where it enters panel, bring all grounds together and connect to ground bar(s), neutrals all run together and to neutral bar, and all hots will go to each breaker. The Neutral on right side shoud be identified with white tape, above the lugs, I see 3 Wires? That just stop, and looks like bare copper conductors. If they are not used, they shoud be capped.
The gray romex that is connect to the bottom right breaker MAY be pulled tight against the neutral(could be the problem).

KISS
Jun 27, 2008, 06:23 PM
Strat:

Hey, your right, there should be a wire from the large ground lug all the way back to the main panel.

Good job catching the uncapped wires and the unmarked neutral.

The chiefengineer has to become the chief technician:

For now, move the bares but jump the neutral to ground bar until a ground is run back to the main panel. Be careful, because the grounds could spark when moving them.

The conductor size should be #1 copper with a #6 AWG ground back to the main panel for 100 A non-continuous. Meaning, breaker can be loaded at 80% forever.

Looks like you have some work to do.

chiefengineer
Jun 27, 2008, 08:12 PM
Again, thanks. I am only an applied mathematician/computer guy... who can
Change starter brushes/program chips/wired whole additions/etc... so why this is such a puzzle stems from the fact
That I always had disconnects I could invoke/test/this has me afraid (none at the house panel... attached as requested... I am too chicken to remove the cover hot).
Also note the banana tree blocking the removal of the panel... not that I
Would do it without a disconnect.

Bummer. The box has almost 300 ft. of concrete all around it (no burials possible).
Why can't I just ground the garage panel in some silly fashion... like through an
Insulated wall pipe I would put in, and forget the breezeway light?

Do U mean "jumper" the neutral to ground or remove the neutrals and
Put them on the ground block?

The garage is semi-detached as in a breezeway roof only... the garage panel extends
To the house in the breezeway switch... the house's sub-panel in the attic controls the
Other part of the mud room.

chiefengineer
Jun 27, 2008, 08:31 PM
One more thing... the pic is dark and there IS a disconnect in the garage panel at the top... just not the house. As you can see the config looks like your diagram:
http://www.ecmweb.com/mag/708ecmCBfig1.jpg without ground wire... unless
It is encased in plastic.

The resolution required here disallows detailed scaled analysis of the box but it is as I described. There are long bare wires which are normally intended to be used as 110V grounds that are being used as both 220V neutrals and grounds... without the neutral bar and the ground bar connected in some way why doesn't this create a hot ground somewhere?

KISS
Jun 27, 2008, 09:49 PM
Your main disconnect is in that panel next to the meter. This should be where the house ground is made.

Those cables that feed your garage panel have to be in conduit. Hopefully there is a ground in there UNLESS someone decided that the conduit IS GROUND which isn't right either.


Do U mean "jumper" the neutral to ground or remove the neutrals and
Put them on the ground block?

Bares to ground bar in garage.
Neutrals to neutral bar in garage.

But, there has to be a ground from the house's reference point. ONE GROUND.

Since there isn't a ground, that we can tell, in the garage panel. A connection from the ground bus to neutral is safer than none at all. This jumper is only a TEMPORARY measure.

So, your "main panel" will then be wired like the sub-panel with separate grounds and neutrals.

Well, since your afraid to take a panel off live, it might be time to call a pro.

Your biggest problems:
a. ground and neutral isn't separate at the garage panel
b. There doesn't appear to be a ground from the main panel
c. Your afraid or can't open the panel next to the meter to turn off power.

Breezeway probably counts as non-detached, so a ground rod isn't necessary.

This may help explain your problem. It's a ground loop and it wrecks havoc.

Ground Loops (or "Let Me Hum a Few Bars…") (http://www.chris-hofstede.nl/stories/transform.php?page=ground.xml)

The bare wire or protective ground should only carry a current under a fault condition.
Neutral is a current carrying conductor tied to the 0 V reference of the house.

When ground carries a current the reference moves and outlet plate screws that are supposed to be at zero volts with respect to the earth aren't anymore and they depend on what the loads are. Furthermore CATV gets affected as well because the signal is ground referenced.

chiefengineer
Jun 28, 2008, 08:21 PM
Your biggest problems:
a. ground and neutral isn't separate at the garage panel
b. There doesn't appear to be a ground from the main panel
c. Your afraid or can't open the panel next to the meter to turn off power.


When ground carries a current the reference moves and outlet plate screws that are supposed to be at zero volts with respect to the earth aren't anymore and they depend on what the loads are. Furthermore CATV gets affected as well because the signal is ground referenced.

Thanks again.

Sorry... am out of town for a few. A + b agreed; c: if I can remove the cover
To get at the screws I will have a go at it. I have no idea why the main cutoff
Should not have a switch that is accessible.

Next paragraph: If I put a multimeter on a regular 120V outlet and connect
Probes to the ground and one plug hole and get a 120V reading would that indicate your
"ground loop" is present?

KISS
Jun 28, 2008, 08:56 PM
Para a:

You put a banana tree in the way.

Para b:

A tester such as this one: AEMC Instruments AEMC 3711 (http://www.aemc.com/products/index.asp)

Between ground and the narrow blade (Hot), you should have 120
Between narrow (Hot) and wide (neutral) you should have 120.

Between Neutral (wide) and ground (round), you should have a very low voltage. Since zero volts rarely exists.

Now in your case, never done it, but it should work. Plug in an extension cord somewhere in the house and go to various outlets/switchplates and measure from the ground of the extension cord and the ground of various other outlets and switchplates. There should be negligible difference.

e.g. Ground of the extension cord plugged into a garage outlet and the outside of the meter disconnect will probably be your largest voltage.

Ground currents is the only effective way, but you can't break the ground and insert a meter to measure it.

Stratmando
Jun 29, 2008, 10:24 AM
If poster has an Amprobe it may help in some instances to measure any ground current.
It looks like a ground to the Meter Can behind the Banana Leaf goes to ground there, I would inspect and verify it is intact. Be careful, if separated from ground rod, it may be live. Stay insulated/Isolated/Safe.

chiefengineer
Jul 3, 2008, 07:45 AM
Para a:

You put a banana tree in the way.

Para b:

A tester such as this one: AEMC Instruments AEMC 3711 (http://www.aemc.com/products/index.asp)

Between ground and the narrow blade (Hot), you should have 120
Between narrow (Hot) and wide (neutral) you should have 120.


Thanks, I'm back.

a) Planted one to the side and a water sucker grew 20 feet
In one year... would've thought myself stupid until I realized I had a contingency:
Screws on top of door appear to be removable. Trouble is: it has been
T-storming like crazy every day and it runs off a metal roof onto the box.

b)Tried this technique in the garage (only 3 outlets). There is ZERO voltage
Ground to ground but about 3.6 OHMS. Hot/neutral is 120V end to end and
Hot/ground is 98V. Does this indicate there is a non-visible ground present
And it is leaking somewhere? Hot/ground in the house is 120V. Panel is as
Depicted still.

chiefengineer
Jul 3, 2008, 07:54 AM
If poster has an Amprobe it may help in some instances to measure any ground current.
It looks like a ground to the Meter Can behind the Banana Leaf goes to ground there, I would inspect and verify it is intact. Be carefull, if seperated from ground rod, it may be live. Stay insulated/Isolated/Safe.

First, thanks for the help. There are a lot of flavors of Amprobes when I googled them(?).
Yes, there may be a ground inside that tube somewhere, but there is no rod in the ground,
Just a solid entrance into the earth. It would seem the house is grounded but whether
That extends to the garage is questioanable.

KISS
Jul 3, 2008, 08:10 AM
98 volts indicates the ground is missing in the garage.

Ground to ground means Ground (panel) to ground (outlet)

3.6 seems a little high, but I don't know what you used for your connections. There may also be an ohm in the leads of the meter. Measuring resistances this low generally requires a 4-terminal meter.

We also know the neutral and grounds hould not be mixed in the garage panel.

Stratmando
Jul 3, 2008, 01:56 PM
I would carefully dig around the conduit that goes out of bottom of Meter Can. It should have a ground rod and Wire Attachment/Clamp. Just remember, if not at ground potential, it may be live.

stanfortyman
Jul 3, 2008, 02:30 PM
Guys, let's not get lost in the fact that a ground rod does NOT ground anything. A ground rod will NOT prevent a shock, and in some instance could cause one.

If you run a 3-wire feeder to a detached structure; ie: no separate ground, and isolate the neutral, a ground rod will ABSOLUTELY NOT "provide" a ground. Any faults to this ground will NOT trip any breakers and will only send current into the earth and bring up worms.

A ground rod is required at ANY detached structure with a feeder. This is NOT the ground that we rely on to cause a breaker to trip upon a short circuit. It is for lightning protection for the most part.
The ground that causes a short circuit is the neutral bond in the main panel. This is carried to a detached structure by a four wire feeder with a separate ground and neutral, both being bonded at the MAIN panel.

Up until the latest NEC cycle a 3-wire feeder was allowed under certain circumstances to a detached structure. This let us run only an insulated neutral with the two hots to the detached structure and bond the neutral and grounds together. The sub-panel in this case is wired exactly as a main panel.
As with the 4-wire feeder a grounding electrode (such as a ground rod) is required.

KISS
Jul 3, 2008, 05:56 PM
I don't think we determined that this is a "detached structure" because it appears to be connected by a breezeway.

stanfortyman
Jul 3, 2008, 06:35 PM
I see. I have to humbly admit, I did not read every word of every post.

KISS
Jul 3, 2008, 07:01 PM
I need to edit mine: I meant to say "we have not determined that this is a "detached structure" since it is connected by a breezeway. Would you consider it "attached" or "detached"?

stanfortyman
Jul 3, 2008, 07:12 PM
That's always a tough call. I really think it depends on the structure.

I think there are only a very few instances where it could be considered detached.
If it is just a small piece of roof between two obviously separate structures I'd call it detached.

KISS
Jul 3, 2008, 07:20 PM
Did you mean attached rather than detached in the following sentence?


I think there are only a very few instances where it could be considered
I think there are only a very few instances where it could be considered detached..

chiefengineer
Jul 3, 2008, 09:49 PM
That's always a tough call. I really think it depends on the structure.

I think there are only a very few instances where it could be considered detached.
If it is just a small piece of roof between two obviously separate structures I'd call it detached.

Background on the breezeway:
It was built/connected to main house (about 20 feet, 6 feet wide) with steel roof.
The steel is not connected to the steel roof of the house (which is galvalume, but the breezeway is bonded to the garage only).

The main house panel feeds the garage panel by a 100A breaker from what I can see. Didn't know there was such a thing, but magic marker says so.

The house and garage "meet" in the lightswitch in the house's mudroom. This is 2 blue plastic boxes separated and one coverplate (plastic).

In terms of digging for a rod, that seems logical... but I also have a whole lot of panels looking identical some of which the coop told me they put in... all in plastic disappearing to earth... maybe it is so complete nothing shows... or maybe they think the transformer protects the circuits?

Stratmando
Jul 4, 2008, 05:28 AM
I haven't read every post either, Did you try turning off breakers 1 by 1 to determine the circuit it is on?
I only mention the ground rod as I thought it was mentioned not present.
The breezeway light has to have both switches ON? Is one switch switching a neutral?

donf
Jul 4, 2008, 09:52 AM
Hi,

Just a point of clarification. You said, "but I also have a whole lot of panels looking identical some of which the coop told me they put in..."

By Co-op, do you mean an Electrical Co-op, or do you mean a Co-op as in a group of co-op owners?

KISS
Jul 4, 2008, 04:31 PM
There is no point looking for grounds when there isn't any. i.e. garage panel
It's obvious it's not there.

The garage panel is in a "detached" structure.
The garage panel needs a ground from the main panel.
The garage panel needs a ground rod.
The garage panel needs to have the grounds and neutrals separated.
The garage panel needs the wiring cleaned up - no sheaths inside the panel.

That out of the way:

The 100 A feeder goes through a conduit?
If so, is it plastic or metal?
If it's metal is is continuous to the main panel?
If so, this could be your "missing ground"
What's the OD of the (wire+insulation"?
What's the wire gauge?
What's the size of the conduit?
Do you think you can fish another wire through the conduit to the main panel?
It can be sized smaller.

KISS
Jul 4, 2008, 04:35 PM
Digging for a ground rod connnection.

Not a useful exercise.

Garage panel doesn't have one.

You need a picture of the inside of the main panel.

You need a picture of the inside of the box next to the meter.

The inside of these components can revel the possibility of a ground rod like the garage panel did.

chiefengineer
Jul 5, 2008, 10:46 AM
Digging for a ground rod connnection.

Not a useful exercise.

Garage panel doesn't have one.

You need a picture of the inside of the main panel.

You need a picture of the inside of the box next to the meter.

The inside of these components can revel the possibility of a ground rod like the garage panel did.


Thank-you for the excellent analysis. I live 30 miles from the gulf and things blow
In quickly, but I managed to look at some radar and get the panel back together
Before a monsoon hit (housePanel.jpg--attached).

As you can see (unless I don't know what I am seeing), there is no main shut-off so
I would have to have a service call to the utility to shut anything off to work on this.

I am guessing the panel is grounded via the meter which I can't open. I have also attached a pic of the rods entering the ground... the meter is the only thing with
Conduit entering the ground... the panel runs are plastic at the point of ground entry
(at least). But no rods anywhere in sight.

The panel has mud dawber nests and cobwebs I would clean up if I could shut it off, and there is a large bare wire touching the panel on
The right. There is no conduit to the garage, just large gauge black encased wire going
Through plastic... if there is a ground to the garage from the house I don't see where it is attached to the house panel. This
Had to be an underground run of about 100 ft. almost entirely under a building slab (the garage). Furthermore the garage panel is in a central plasterboard stud wall far from
Any potential outside grounding location. It would appear I'd have to go up out the panel
Through the attic and back down... and although there's a shut-off in the garage, there's none for what feeds it (?).

My next move will be to move wires as suggested in the garage panel.

donf
Jul 5, 2008, 11:21 AM
I'm new to this thread, but I'm curious if you made sure the switch plate was properly grounded to the switch?

You ground the plate by using the bare wire ground to the screw in a metal box. If the box is plastic, attach the ground wire to the switch's grounding screw. Once the switch is grounded, then the metal faceplace will be grounded when it is mounted to the switch's yoke.

KISS
Jul 5, 2008, 11:45 AM
Plastic is conduit. This looks like an outside panel which provides a bunch of disconnects to smaller panels. I'm not sure what I'm seeing here either, but if you can get a vacuum cleaner hose and clean out the cobwebs, and take another picture that would be great.

It won't bite down at the bottom. That doesn't look like an enclosure appropriate for outside.

KISS
Jul 5, 2008, 02:33 PM
This looks like your main panel. There is a screw to the right of the large middle cable coming in from the top. This looks like the bonding screw.

If you get the cobwebs away, we can see how many wires are going to the meter base.

From what we seen so for, the existence of a ground rod is slim.

Is it time to put a lid on this can of worms?

KISS
Jul 5, 2008, 02:35 PM
The outside enclosure should probably be rated NEMA 3 or NEMA 3R. I don't think it is.

See: http://www.admeng.ca/documents/Nema_Enclosures.pdf

KISS
Jul 5, 2008, 02:40 PM
This would be the likely place to feed the garage panel.

chiefengineer
Jul 5, 2008, 03:08 PM
There is a screw to the right of the large middle cable coming in from the top. This looks like the bonding screw.



I thought of blowing the thing out before the big rain hit, I could let the T-storms
Wash the whole thing out but it'd probably kill my box. (see my forecast... little
Likliehood I'll get in there soon). Yes, the box is old and bent... Square D 20 yrs. Old,
Put in by the coop.

The bonding screw on the top middle is a ground? That would explain why I just did
The following which seems to have "solved" the grounding mystery:

I had time to cap all the loose wires with tape
In the garage panel, then moved the 220V ground
Wire that was on the right side ground bar to the
Right side neutral bar.

I also carefully inspected the power coming from the
Outside panel's 100A breaker and found the wires to be
Of an immense gauge... probably 6.

There were 3 on wires on the uppermost
Take-off that led from the bottom of the panel, yet only
Two coming from the main panel breaker. This led me to suspect that
One of them is a ground(!) leading somewhere into the dirt
That I can't see... possily because they built onto this garage
Structure behind it and left the ground underneath(?).

I checked a couple of outlets and got 115V ground to hot after
This switch.

chiefengineer
Jul 5, 2008, 03:15 PM
I'm new to this thread, but I'm curious if you made sure the switch plate was properly grounded to the switch?

You ground the plate by using the bare wire ground to the screw in a metal box. if the box is plastic, attach the ground wire to the switch's grounding screw. Once the switch is grounded, then the metal faceplace will be grounded when it is mounted to the switch's yoke.

This seemed like an excellent idea to me, as I had just done this... see my attached pics.

After I switched the 220V wiring in the garage
panel to look identical (all 3rd wires to neutral bar)
I retested the breezeway switches and got identical test
results to the original test.

I pulled the garage switch controlling the breezeway light
and took two pictures (attached). There are two groups of
romex for this switch (my analysis may be wrong here):

Romex 1 = Ground on neutral terminal on left side
Neutral wire to neutral terminal on right side
Hot married to Romex 2 neutral
Romex 2 = Hot to hot terminal on left side
Ground to ground
Neutral married to Romex 1 hot

Oh, and one thing I noticed was that the ground screw was on
the top of this switch, which after seeing these high res
pics indicates this switch is upside down. Do you think
the installers noticed such a thing... or should I proceed
to rewire this as is except right side up?

Stratmando
Jul 5, 2008, 03:39 PM
On single pole switches I install with 2 screws to the right side, this makes it up for on.
On 3 ways I like to maybe turn one "Upside Down" if needed so when all switches are switched off in multiple locations and 3 and 4 ways, everything is off. In the photo , it almost looks like the switchleg(white wire) made contact with the ground on single pole switch, If they touch when switch is installed and shock occurs when light is on(3 way light). Then that may be problem?

stanfortyman
Jul 5, 2008, 05:08 PM
HOLY CRAP Engineer. Who ever wired that should be shot then arrested!

They are using a bare ground wire as a current carrying conductor. They didn't run a 3-wire for the 3-way switch so they used the ground wire!

See the top picture.

KISS
Jul 5, 2008, 06:05 PM
There were 3 on wires on the uppermost
take-off that led from the bottom of the panel, yet only
two coming from the main panel breaker. This led me to suspect that
one of them is a ground(!) leading somewhere into the dirt
that I can't see...possily because they built onto this garage
structure behind it and left the ground underneath(?).


Kind of, sort of.

Taken by itself. It is a ground or a neutral. Problem is you need two wires connected to the same point at the other end, but you can use an 8 AWG for ground.

Based on what stanfortyman said (I think), it's permissible (old code) to use this as a neutral and have a ground rod for ground. New code reguires a ground rod and a ground.

KISS
Jul 5, 2008, 06:14 PM
The left view seems to show the bare wire being used as a current carrying conductor. That's not right.

Time to start over?

If you don't have the time to do it right, when you going to find the time to do it over?

Have about the same weather forecast where I'm at, but the Gulf's water temperature is very comfy. I'm about 100-150 miles from the Atlantic Ocean. You'll just have to be fast and do it between the rain drops. <G>.

stanfortyman
Jul 5, 2008, 06:31 PM
Based on what stanfortyman said (I think), it's permissable (old code) to use this as a neutral and have a ground rod for ground. New code reguires a ground rod and a ground.It's not that you use a ground rod for the ground. This is not possible since a ground rod does NOT provide or create a ground.
If under recent codes a 3-wire feeder (sans ground) was run to a detached structure you would then bond the neutral to the panel same as a main panel. THIS is where your ground comes from.

Stratmando
Jul 6, 2008, 04:57 AM
Stanforty, I totally missed the bare a for current carrying conductor, if it connects to other bares(grounds) then we see where problem may be.
I now worry about the rest of the house, same electrician?
You can do X10 for 3 way lighting should getting another conductor not be easily done.

stanfortyman
Jul 6, 2008, 06:58 AM
I now worry about the rest of the house, same electrician?
You can do X10 for 3 way lighting should getting another conductor not be easily done.I agree on both counts!

chiefengineer
Jul 6, 2008, 07:05 AM
First, I want to thank everyone who has added to these threads;
I hope the solution outlined below is a noteworthy piece of
Sleuthing for future readers(?).

I couldn't sleep well last night as problems like this
Bug me. Why, after wiring my whole two story addition with electric,
HVAC, jaccuzzi, an in-wall computerized surveillance system, etc.
Was I stumped by these switches? Had I learned nothing?

It dawned on me that there were actually SIX wires to switch number one,
Not just the measly four
Required to do a "Fixture Between Two Three-Way Switches: Power Through Switch" configuration. Having lived 14 years in southern Missouri
Learning to fix anything without going to town first paid off with this
Strange conclusion: "lots of extra wires here to play with = no one who wired this could be this big a bozo."

So here's what conclusion(s) solved this:

1)Bare ground used as conductor is creating shock hazard
And therefore must have another purpose in life.

2)There is no reddish "common wire" to toggle these switches,
Or if there is, it is unpainted/unidentified, therefore
White must be intended to be that "common wire" since for no
Apparent reason it is on the common terminal of the garage switch.

3)Since there are no rubbing/crossed wires switch (#3) in mudroom must be wired wrong even though it is black/black,
White/white, ground/ground, (thus, the bozo factor is reincarnated elsewhere).

To the mudroom and switch number three...
Moved white to common and ground to neutral. Light toggles from
Both ends with no shocks at either switch.

Now before I break my arm patting myself on the back and probably reward
The person most nearly headed in this possible solution/direction for simply
Rewiring in a backwards-looking fashion the very switch that titillated a guest, there
Is the small matter of no ground on mudroom switch 3 (it is terminated
At the light). So unless someone says "Oh my God I wouldn't sleep in
that futute heap of smouldering ashes" I'm going on my merry way to
Solve the unending mysteries of how things get done
Around here.

KISS
Jul 6, 2008, 07:37 AM
In the meantime, wire the ground and neutral busses in the garage panel together and see if things improve.

I'll look at your latest post later.

EDIT: This will at least get you close to the "old code".

- Work on getting a ground rod at the garage panel for lightning protection.

- Clean up the wiring in the garage panel
... Tape the neutral white
... No cable sheaths in the panel

chiefengineer
Jul 6, 2008, 01:05 PM
In the meantime, wire the ground and neutral busses in the garage panel together and see if things improve.

- Clean up the wiring in the garage panel
......Tape the neutral white
......No cable sheaths in the panel

I wrote this yesterday at 10:08AM:
"
I had time to cap all the loose wires with tape
in the garage panel, then moved the 220V ground
wire that was on the right side ground bar to the
right side neutral bar.

I also carefully inspected the power coming from the
outside panel's 100A breaker and found the wires to be
of an immense gauge...probably 6.

There were 3 on wires on the uppermost
take-off that led from the bottom of the panel, yet only
two coming from the main panel breaker. This led me to suspect that
one of them is a ground(!) leading somewhere into the dirt
that I can't see...possily because they built onto this garage
structure behind it and left the ground underneath(?).

I checked a couple of outlets and got 115V ground to hot after
this switch."

Let me explain: I attached a pic of the garage panel (all cleaned up as I indicated yesterday) at the top. The middle lead with the bonding screw is circled by a red donut.
This is attached by the large black 6-8 gauge sheathed cable that leads either through the bottom of the panel to a ground in the house panel or to a grounding rod under the garage addition. The hot/ground readings all came back normal.

I don't know how further to test this except everything works perfectly and there is
No more live ground. Perhaps the best test was the huge lightning strike on the transformer a few feet
Outside this box last year... nothing was injured(?)

KISS
Jul 6, 2008, 03:06 PM
The life preserver shows where the neutral/ground bond screw would have been.

Stratmando
Jul 6, 2008, 03:43 PM
Kiss, is the Middle Neutral, or the one on the right, the orange cable covers.
Chief, can you look at and confirm the Lug and wire that connects to Neutral bar?
Left, Center, Right?

KISS
Jul 6, 2008, 03:59 PM
Strat:

Post #7 has a better picture of the entire panel. The terminal in the donut is neutral.

Chief should place a wire between the ground and neutral bars or put in the missing screw. This is more apparent in post #7.

chiefengineer
Jul 7, 2008, 10:26 AM
Thanks for all the feedback.
As requested here are 3 confirmation pics.

One shows all the connections from the main house panel
To the garage panel. Note the striped cover on the neutral,
What I perceive to be a grounding block on this wire that
Has been taped (why, if this is desirable?), and the absence
Of a neutral/ground bond.

The next shows bare cables capped and a close-up of the
Garage panel with the striped neutral and also no neutral/ground bond in
The box (but couldn't there be an in-ground block to this I can't see?).
BTW these take-offs are LIVE (pre-cut-off) and it seems to me to run a wire
From neutral to ground could fry me without calling the electric co.
Out to shut off the transformer (what am I missing?).

The third shows what I perceive to be the ground on the house panel
Housing. Since there are no ground wires in this panel and many
Bare neutrals touch the housing doesn't this create a neutral/ground bond
And therefore to the garage also?

KISS
Jul 7, 2008, 11:45 AM
In the first picture the "Too nothing" may not be a bond screw, but I can't see the hole at the top which I'll assume is there like in the lower picture.

So let's assume thAT THE GROUND/NEUTRAL bond is in the meter base which is OK and that this is the main panel.

The second picure is the garage panel. If I remember, it had two busses of wires all mixed from neutral to grounds.

Just connect a wire from the set of neutral terminals to a set of ground terminals. They are all mixed right now, which is OK. What it will do is give the garage panel it's own reference and not have any dependencies on what the garage panel is drawing. There will be a reference potential difference between the main panel and the garage panel, but since you don't typically put one piece of equipment in the garage and another in the house and connect them together with a grounded conductor, this is the best option.

A ground rod in the garage will help prevent lightning damage eminating from the garage circuits, otherwise a hit in the garage, must travel through the neutral to the main panel and (as we believe) to the neutral ground bond in the meter base to the ground ron.

A hit near the transformer should follow a path to ground at the transformer.

An overhead line is more likely to get hit.

Not too bad:

At least you got the shocking switchplate fixed. In all likelyness the original installation was not inspected.

Make sense?

When can we come for vacation? Assuming you have "shocking switchplate" insurance.:D

chiefengineer
May 2, 2010, 12:45 PM
My disability has worsened and I have
a free disconnect for tree removal coming,
so I thought I'd get some of the grounding
done the kind people in this thread suggested.
The first step would be a main cut-off for the
main panel (see first pic in POST#54 above).

Looked like an easy 200A Square D main breaker until
I added up the amps this main panel supports (the
identification on it is faded out). I added the
max possible simutaneous usage amps on the right:

House sub-panel: 100A breaker to 125A panel = 98A
Garage sub-panel: 100A breaker to 200A panel = 50A
Oven: 40A breaker = 33A
Well pump: 20A breaker = 17A
Central Heat: 100A breaker = 82A
Dryer: 30A breaker = 28A
A/C: 40A breaker = Not used with heater
Total = 308A

Therefore this panel must be rated >200A and I need a
bigger cut-off? This maximum usage combination has never
happened that I know of and I would prefer not to use
my inductive ammeter on a live panel. Note: central heat
is used RARELY.

Who else would forget about this whole "problem" and leave
it as it has flawlessly existed for 25+ years.

stanfortyman
May 2, 2010, 01:08 PM
The way you added everything up is meaningless. That is not the way to do a load calculation.

WHY do you need a main disconnect for a main breaker panel?

chiefengineer
May 3, 2010, 07:40 AM
Great question. I have never seen one without before.
Electric company says it is now code so "this is an opportunity".
But from a practical standpoint, my house subpanel has
No main disconnect... it uses the 100A breaker in the main panel as one.
Therefore if that breaker starts to trip I have to call the electric company
And have disconnect fees... or if any of the main breakers fail, same thing.
Or if I want to clean out all the wasps nest without personally igniting.
Earlier in this thread it was suggested I run a ground back to this main
Panel from my garage panel... etc.. However everything works now.

I agree; I was using a home-repair manual from the library which listed amps/watts
For sizing purposes. If it's wrong, it's wrong... I thought that myself... what are the
Odds I'll run a welder when the furnace, oven, dishwasher, and 50 lights are all on? Zero.

donf
May 3, 2010, 08:10 PM
Just a suggestion, but it looks to me like you have a MLO panel being fed by conductors passing through the meter nipple and into the "Main Panel(?). I'm looking at the pic of the meter that has the hornet's nest in it. This is the panel that feeds the entire home, correct?

More than likely, this panel conformed to the "Six or Less" switches and therefore did not need Main Panel Disconnect.

Next, the breaker to feed the garage is added to the panel and now have a code violation. Because you now have 7 breakers in this panel, you must either add a main cut off switch in front of the panel connections. Or replace the panel with a panel board that does have a Main panelboard disconnect.

Is there a sub panel inside the residence? If so where and can I see a pic of that panel.

Last, can you please tell me which panel is in the garage and give me the pic reference to that image.

With all the discussion that been going back and forth here, I'm surprised no one has asked you for a breaker layout.

All of the breakers you show in the Main Panel are 240 VAC breakers, where are your general branch circuits?

Whoever did the wiring of the switches needs to be sued whether he filed bankruptcy. He criminally endangered your residence to fire hazards.

Have these panels been inspected by both the fire department and the city/county/state electrical inspectors.

Personally, I find it hard to believe that the Electrical Co-op didn't at least tell you why you have a code violation.

I'm a math and computer guy myself and I'd like to tell you that you can reduce electrical wiring down to 'binary events", but you cannot, electrical wiring is not that simple. Your residence has serious wiring problems!

I read in one of your posts that your disability has degenerated, if you don't mind, will you tell us what the disability is. Some of the work that has to be done may be physically outside of your abilities and this may have to be attacked from a different direction.

Just trying to help you.

chiefengineer
May 4, 2010, 05:51 AM
Thanks for your explanation of code.
The Electric Company had no knowledge of a "6 vs.7 violation".
I simply asked if during their tree trimming I might slap in one of these:
Shop Square D 200-Amp Main Lugs Rainproof Main Breaker at Lowes.com (http://www.lowes.com/pd_103873-296-QOM2200VH_0_?productId=3127509&Ntt=square%20d%20breaker&Ntk=i_products&pl=1&currentURL=/pl__0__s?Ntk=i_products$rpp=15$No=30$Ntt=square%20 d%20breaker$identifier=)
To make my main panel off the meter "non-MLO". They commented "it would be an opportunity to bring it up to code".
This is a remote rural area and if building inspectors existed I would not
Have had a shocking switchplate. The volunteer fire department is so far away they'd
Never make it, and I believe they're disbanding anyway. Unfortunately or not,
People do whatever they please here.

The best explanation of "general branch circuits" is what I laid out in POST#56 above.
They ARE the breakers in this box, feeding everything: other panels, A/C, stove, etc.
If you mean circuits like "fixed kitchen appliances" they are one my house subpanel.
I am very happy with those... as a math guy you might appreciate this: I analyzed
Them with various on line power-supply calcualtors using Volt-Amps before adding to any.
They are efficient. Nothing has ever tripped. I tested each breaker physically.

The garage panel was added by a bankrupt contractor. He employed the backwards
Switch-wiring "no ID" laborer ever-so-common here. There were so many cost overuns it
Also bankrupted the former owner of this house, who I bailed out with my purchase.
The best picture of the garage panel is on this page:
https://www.askmehelpdesk.com/electrical-lighting/shocking-switchplate-231047.html
A direct link as of this post is here:
https://www.askmehelpdesk.com/attachments/electrical-lighting/9681d1214588009-shocking-switchplate-garagepanel.jpg

Although I have no pic of the residence subpanel, it is a Square D Panel rated for 125A which has no main cutoff, 18 20A breakers, and one 30A for the water heater.

I could write a boring medical journal on my physical challenges. I can best summarize it
This way: I have neuro-muscular issues that restrict what I do to the degree I
Am willing to extend daily hydrotherapy, which can be quite burdensome. I am capable of
Installing a main cut-off but my days of downing oak trees is near an end. My analysis was more
Linear than the concept of Volt-Amps... it was how many pure amps, including compressors
And motor surges might conceivably be in simultaeous peak demand. Modeling software smooths
This out. I simply don't want to create a problem where one doesn't exist.