Manche757

Somewhere along the line, your ground and neutral have been mixed. In 1969, your house had a 3 prong outlet in the bathroom? Refrigerator? Washing machine? All others have 2 prong outlets? The bathroom reads 120v suggesting the ground is good. Can you tell if the boxes in the bedrooms have the any grounding wire either to the inside or the brown one you found on the back of the boxes in the kitchen? I would have expected the bedrooms to show 120 if the boxes were grounded or zero if not. Check your branch panel in the shop. The ground and neutral should NOT be attached to the same bar.. Under the kitchen sink looks suspect. Find out what the white lines lead to. Is the dishwasher wire run to one of the two kitchen circuits or does it run all the way to the panel? Flip off the breaker to the ceiling fan in case someone attached the fan ground and neutral to the white neutral.

Hope you had a productive night at work. Your electric panel looks like it replaced the original one. The yellow wire nuts on the neutral white lines are a give away. The lines moved from the original panel were not long enough and were spliced. It also looks like a 120 v circuit and a 220 v circuit were added after the new panel was installed. There is a gray jacketed cable that comes in at the top right of the panel and crosses over and down the left side. The jacket is a give away. Is the black wire loose and just butted against the lower breaker? I can not tell from the picture. If so, pull it away and put a wire nut on the end of it , or tape it off. The prior owner added a circuit then removed it. If that is the case, also remove the neutral and ground from the grounding bar. Any guess what the prior home owner added but then removed? Other than that, your panel looks to be in good order. The 220 v circuit on the lower left also looks to have been added and looks to be in good order. I don't how much experience you have working in an electric panel but regard everything as hot. Only use tools with insulated tools.. I can not tell for sure from the picture but it looks like you have a main breaker at the bottom to shut off the panel. Only turn it on or off with everything in the house turned off. Especially big drawn items. Rubber sole shoes only. Floor dry of course. The only way to kill everything is to pull the meter. The silver bars in the middle are hot. The large middle black cable connects to the power company just as each of the two 120 volt single phases do. There is a brown ground on the right lower panel. The pic is not totally clear. Does that ground run through a grommet in bottom right corner of the panel? A second line returns next to it? That ground should be connected to the grounding rod you hammered into the earth. I would have left it above ground to mitigate corrosion and damage from digging blindly. Are there 2 conductors attached to the rod? One line may find its way to all the outlet boxes in your house; based on your earlier comment about brown wires hooked to the back of each box. A good thing. With your tester, go to several outlets in your house and touch the hot side of the receptacle and the center metal plate between the receptacle. (If the covers are on, touch the center screw holding the plate on. If you get 120 v, good. If anything lower, paint on the screw may cause the drop. Take the plate off and touch to the center metal.) You mentioned above that you might have reverse polarity on a living room receptacle. Black wire should be connected to the copper screw; white to silver one. Small slot on the front of receptacle is hot, larger one is neutral. Sorry to have insulted your intelligence for all you already knew.

No. Just turn off the breaker to the light circuit. Chances are you have a separate light circuit (so that lights don't dim when something drawing a lot of power turns on. And also so lights don't go out if you trip a breaker to something other than lights.) Chances are the ceiling fan is tied into the light circuit.

later

Good work. It is a process of elimination. Somewhere there is a feed back into the grounds. Did you unplug everything in circuits 1 and 2 and test? Especially circuit 2. A faulty small appliance or lamp could produce the results. The ground is attached to the boxes in both circuits 1 and 2, right? Look around and see if you can find what the ground is attached to. It could be tied into the neutral somewhere out of the panel - against code. It also could have been attached to a grounding rod outdoors. Code for your area determines the depth that the grounding rod needs to reach (to stay in wet dirt). In Virginia Beach, that depth is only 8 feet. The highest point above sea level here is only 145 feet and that is a landfill destined to be covered with soil and turned into a park. Someone could have run it back to the panel, which would be the best. It also could have been attached to a water pipe. Code says it should be attached to a metal cold water pipe where it first enters the building. Look at the cold water pipe on top of your water heater and see if you see more than just the one grounding wire that runs to the electric panel. The two white lines are not wired together? The next process would be the time consuming process of looking in the boxes for circuits 1 and 2 and see if the hot wire is touching the metal box anywhere. Got a flash light handy? The grounding line for the circuits 1 and 2 likely are connected. If you can find where, separate one circuit's ground.

that living room circuit is likely on one of the two kitchen circuits. Are the two white wires that you capped off connected?

With the extension cord, you were able to figure out which end of the extension plug is neutral? The assumption is that you have copper pipes and not pvc or pec

It if arched, it is hot. Are the ends of the two (are both white as it looks in the pic?) exposed and not taped off?

That is good. Stove circuit is ok. Stove itself is ok. That is a 50 amp circuit. Amps, not voltage, is what kills people. So the stove and circuit is not leaking power. It is providing ground from the leaking ground in the wall circuits.

In that last pic, are there 2 white single wires? What are they connected to?

Good job getting the test reads. Confusing results though suggest grounding in different circuits. Test voltage from stove to cold water pipe.

Unplug everything on circuit 2. You might not know where that goes through your house. In 1969, there might have been only 2 or 3 120v circuits for the entire house. With the breaker for circuit 2 off, do the same test again. Tester to black and white at receptacle and tester to white and to stove. With the 1volt read, it is possible that a lamp or other low draw appliance is providing the feedback

Lets label them circuit 1 and circuit 2. The first being the one that you had a zero read on. Circuit 1 looks to be ok. Circuit 2. Ground is energized and now to find out where. To confirm you got a 1 volt read with the circuit breaker off?

ok you have found the suspect circuit.

Also using the first circuit, and using the tester, touch the white neutral and the stove. What reading do you get?

That circuit should be ok. Go on the the other circuit and do the same test. Unplug anything that might be plugged in

Thanks. Turn the breaker off to that circuit. With your tester, check to see that the outlet is off. Then using your tester, touch the box and the white neutral side. What reading are you getting on your tester?

Cut off the paper insulation before you retake pic

Before 1969, grounds were not required but might have been there. Often in the 60's grounds were on the bathroom circuits but not for the rest of the house. In the 60's, the ground wires were allowed to be of a smaller gauge wire. That is no longer allowed. I assume your state follows the BOCA code. How many conductors are in the gray jacketed cable feeding from the top? Black and white with no bare ground? Can you lift the black cable coming out of the box and take a pic?

There is no short but instead the grounding wire is picking up current somewhere. What is not known is how many boxes the grounding wire is hooked to. You will need to go by process of elimination to find the contact. Earlier, you indicated that you have two brown wires along with is likely a grounding wire. How old is your house? Was it built before 1940? It might have knob and tube wiring. Conductors were both black (could have faded to brown.) One is hot and the other neutral and they look the same. Do you have black and white conductors or two old ones that are same color with thick insulation that looks kind of like cloth/asphalt?

The grounding wire is energized somewhere along the line. It energizes all boxes it is connected to. The problem has likely been there prior to your backsplash project. It was noticed becuase of the wet mortar. Flip breakers one at a time and isolate the circuit with the corruption then look for the ground to hot contact in that circuit.

I am not clear we are on same page, lets play this safe. Pick the most likely circuit. Take off cover plates and pull recepticles ou of wall. Then turn that breaker on. Now see if you show a hot box

Breakers on or off?

By attached to back of box, do you mean back of inside?

Second question about tapping into 220 line is bad news. Let solve other issue first