Neutral Wants to Follow Ground

[ramsy]

Because the static electricity is not coming from any of the electrical wires.

Since when are grounds not electrical wires?

 

[oldsparky52]

This has me thinking about a typical residential service installation--the ground wire is not normally supposed to be carrying current. But it's joined to the neutral so the current will go the way of least resistance. I haven't checked many ground wires coming out of services toward electrode for current, but I have a handful of times and only seen current once. The one coming out of my house doesn't show any current. I guess this means the "neutral" coming in from POCO is less resistive than the grounding wire to grounding electrode installation. I know that stray currents to ground are a problem in some places.

I think more current will go the way of least resistance, but current will take all paths of resistance according to the resistance. More resistance, less current.

The path for current from home through the ground rod to earth on it's way back to the transformer is one of pretty high resistance.

 

[kwired]

This has me thinking about a typical residential service installation--the ground wire is not normally supposed to be carrying current. But it's joined to the neutral so the current will go the way of least resistance. I haven't checked many ground wires coming out of services toward electrode for current, but I have a handful of times and only seen current once. The one coming out of my house doesn't show any current. I guess this means the "neutral" coming in from POCO is less resistive than the grounding wire to grounding electrode installation. I know that stray currents to ground are a problem in some places.

The current is trying to return to the source not the earth. Earth is a possible path, but as long as the grounded service conductor is in good condition it will have much lower resistance than the grounding electrode in nearly all instances, exception being when the grounding electrode is a water pipe and it is continuous to other services, there is where you may see a pretty significant amount of current on the grounding electrode conductor, but is not considered objectionable current by NEC in this case.

Current doesn't take the path of least resistance, it takes all possible paths, but path of least resistance is going to carry the most current of all the paths.

 

[kwired]

Since when are grounds not electrical wires?

They are, but the current carried in the static shock incident isn't related at all to the source for the premises wiring. You have a charge built up in you , you touch the object that has a path to earth and that charge is equalized by letting it discharge via that conductor, or depending on polarity of your static charge you could be absorbing electrons from the earth to equalize the charge - still is about same experience to you either way.

 

[flashlight]

"The path for current from home through the ground rod to earth on it's way back to the transformer is one of pretty high resistance."

"Current doesn't take the path of least resistance, it takes all possible paths, but path of least resistance is going to carry the most current of all the paths."

This explains why current is splitting up between white wire and green wire as it leaves barn, but going back to transformer from house only on white wire.

 

[ramsy]

They are, but the current carried in the static shock incident isn't related at all to the source for the premises wiring..

As stated in #17, power line transients with higher voltages, need not be related to source when traveling thru garage, to house sub panel,
to common-electrode ground, but --can shock people in the path-- just like static electricity.

Out-building EGC to Neutral bonds were prohibited since the 2008 NEC. Without separate service, this energizes all bonded surfaces in the return path thru house sub panel in the OP's case.

Electric shock doesn't need to cause damage, burns, or fire to kill. Much less does electricity need good-conductivity to put 30mA thru the heart, known to be fatal.

My point in #17, OP is right to remove EGC bond at garage, until separate service is connected.

 

[Another C10]

I looked at the bonding jumper and thought, well, this
will be service equipment so I might as well do it now.

This may of been mentioned, My thoughts are if I read the post correctly, everything at the barn was fine until bonding or joining the neutral and ground together, which is fine at the main but there is no main at this point in time for the barn, My theory would be the neutral is bleeding off somewhere between the house and the barn therefor the ground is also acting like a return to a less restrictive path. Try removing the bond at the barn and see if the ground is still energized with current, remember a grounding conductor is a safety valve not meant to have any current flow unless its a fault current.

 

[kwired]

As stated in #17, power line transients with higher voltages, need not be related to source when traveling thru garage, to house sub panel,
to common-electrode ground, but --can shock people in the path-- just like static electricity.

Out-building EGC to Neutral bonds were prohibited since the 2008 NEC. Without separate service, this energizes all bonded surfaces in the return path thru house sub panel in the OP's case.

Electric shock doesn't need to cause damage, burns, or fire to kill. Much less does electricity need good-conductivity to put 30mA thru the heart, known to be fatal.

My point in #17, OP is right to remove EGC bond at garage, until separate service is connected.

Well we were talking about low voltages (as in 600 and less) medium and high voltages can be more risk simply because there is so much more voltage to push current through what is considered an insulator at low voltages. Typical static electricity you run into just from walking across the floor might be thousands of volts, but typically has very limited current and energy behind it. Yes if a transient that originated on the medium volt lines finds it's way onto your grounded service conductor it could present you with some hazards, but if you are standing on a wood floor and touch something connected to the EGC during this transient you probably still pretty safe most cases

Yes it is good idea for OP to remove the bond until he actually has service conductors as the supply.

 

[oldsparky52]

This may of been mentioned, My thoughts are if I read the post correctly, everything at the barn was fine until bonding or joining the neutral and ground together, which is fine at the main but there is no main at this point in time for the barn, My theory would be the neutral is bleeding off somewhere between the house and the barn therefor the ground is also acting like a return to a less restrictive path. Try removing the bond at the barn and see if the ground is still energized with current, remember a grounding conductor is a safety valve not meant to have any current flow unless its a fault current.

I don't understand what this means, can you elaborate?

 

[oldsparky52]

This may of been mentioned, My thoughts are if I read the post correctly, everything at the barn was fine until bonding or joining the neutral and ground together, which is fine at the main but there is no main at this point in time for the barn, My theory would be the neutral is bleeding off somewhere between the house and the barn therefor the ground is also acting like a return to a less restrictive path. Try removing the bond at the barn and see if the ground is still energized with current, remember a grounding conductor is a safety valve not meant to have any current flow unless its a fault current.

The current on the ground would go away once you remove the bonding jumper because it would no longer be a parallel path for current. Since the current divided 3/6 on ground and neutral, it means that the ground path has twice the resistance of the neutral path. To me, that is a concern, and the "safety valve" may not be as safe as we desire.

 

[kwired]

The current on the ground would go away once you remove the bonding jumper because it would no longer be a parallel path for current. Since the current divided 3/6 on ground and neutral, it means that the ground path has twice the resistance of the neutral path. To me, that is a concern, and the "safety valve" may not be as safe as we desire.

Still can a little bit of a situational thing.

If both conductors are same size, type and length, then definitely a concern.

But if you have say a 200 amp feeder with full neutral of 3/0 and minimum required EGC of only 6 AWG, I'd expect there to be more resistance on the EGC in this situation.

 

[Another C10]

The current on the ground would go away once you remove the bonding jumper because it would no longer be a parallel path for current. Since the current divided 3/6 on ground and neutral, it means that the ground path has twice the resistance of the neutral path. To me, that is a concern, and the "safety valve" may not be as safe as we desire.

What I said actually makes no sense as you state ?, Sorry I'm not understanding what you don't understand, either way regardless of all the variety of theories amungst the many intelligent people here, adding a bond at a sub panel does allow for the second return back to the main, if there was a difference in current as I thought was mentioned somewhere, lets say favoring the ground conductor, I'd consider the neutral had more resistance possibly through leakage from depleted insulation causing ( bleeding ) if the currents were the same then yes its just a secondary path for the return.

To all, I really enjoy this group and thank you for having me but I have to be honest its a little brutal in here. articulating with tact I know is challenging but sometimes maintaining respect is more important than the argument itself.

 

[ActionDave]

....To all, I really enjoy this group and thank you for having me but I have to be honest its a little brutal in here. articulating with tact I know is challenging but sometimes maintaining respect is more important than the argument itself.

Welcome to the forum. Sacred cows are slaughtered here without remorse. The upside is you get a whole lot smarter than you ever dreamed possible.

 

[kwired]

What I said actually makes no sense as you state ?, Sorry I'm not understanding what you don't understand, either way regardless of all the variety of theories amungst the many intelligent people here, adding a bond at a sub panel does allow for the second return back to the main, if there was a difference in current as I thought was mentioned somewhere, lets say favoring the ground conductor, I'd consider the neutral had more resistance possibly through leakage from depleted insulation causing ( bleeding ) if the currents were the same then yes its just a secondary path for the return.

To all, I really enjoy this group and thank you for having me but I have to be honest its a little brutal in here. articulating with tact I know is challenging but sometimes maintaining respect is more important than the argument itself.

Tact is challenging, especially when not talking face to face. No body language or even differences in tones can make the same written words seem different.

Just stating what I believe are facts here, depleting insulation will not change the resistance of the conductor within that insulation. However it can allow unintended connection to something else that is conductive and that will allow more potential paths for current, but that is more likely to lower the resistance of the total path instead of increasing it, and possibly part of why the EGC is carrying more current - it potentially has other paths by nature of how it is used, it is bonded to many things that are not intended to carry current during normal operation. If you ran same size and type insulated conductors in parallel from outbuilding they should have same resistance, IIRC (might be thinking of something in another thread) I thought he supplied this from either a feeder panel or even just a receptacle outlet in the house and not from the service panel and there was metallic wiring method involved with that feeder/branch circuit, this could easily mean a difference in resistance in that segment of the total run on the EGC. Might be more resistance but many cases probably less.

 

[kwired]

Welcome to the forum. Sacred cows are slaughtered here without remorse. The upside is you get a whole lot smarter than you ever dreamed possible.

I agree. Will also say that even if you take something the wrong way you won't see the pretty obvious bullying like you will see on most other similar type sites, owner of the site doesn't want it and those that moderate it do a pretty fair job of handling it if it does happen.

 

[flashlight]

"I agree. Will also say that even if you take something the wrong way you won't see the pretty obvious bullying like you will see on most other similar type sites, owner of the site doesn't want it and those that moderate it do a pretty fair job of handling it if it does happen."

I totally agree, also with the earlier post about this site's ability to make you smarter.

I did unbond the neutral until I disconnect the temporary feed. But before I did I took some more readings
with various things running, such as small table saw, bench grinder. This time it wasn't 6-3,
it was 8-2. Maybe rain or lack of it affected resistance to ground.

 

[Another C10]

I did unbond the neutral until I disconnect the temporary feed. But before I did I took some more readings
with various things running, such as small table saw, bench grinder. This time it wasn't 6-3,
it was 8-2. Maybe rain or lack of it affected resistance to ground.

I'm curious if you get an amperage reading still with the Neutral/Ground separated again. My guess would be probably so, which then would lead me to believe that the insulation of the SO is more than likely depleted somewhere along the line , Is the SO underground or above ground.

 

[flashlight]

I was thinking of the resistance of the actual ground rod at house, but SO is run on top of the ground.
It's brand new, seems to have all it's integrity but nonetheless I will glad to be rid of it.

 

[Another C10]

I was thinking of the resistance of the actual ground rod at house, but SO is run on top of the ground.
It's brand new, seems to have all it's integrity but nonetheless I will glad to be rid of it.

I have a moment to elaborate on my thought during this slow period of sitting in front of this computer, Let me recreate the scenario I imagine.

Barn is fed from house panel,... new SO cord from house panel feeds barns sub panel which runs above soil. ...You bonded the ground and neutral together at the sub panel, ...you put an amp probe on the ground and got a 3A reading you got a 6A reading on the neutral both separately measured at the home panel side of this new SO cable. ...You then removed or isolated the sub panel ground/neutral bond and turned on some additional loads within the barn, went back to house panel then remeasured the same ground and neutral of the new SO cable to now find 8A on the neutral and 2A on the ground ... I'd suggest that there is stray voltage from a branch circuit in the barn sending 2 amps ( 240w ) back on the barn ground within the barn sub panel which is getting measured with the amp probe over at the house ground wire of the new SO cord. ... just a thought.

 

[kwired]

I have a moment to elaborate on my thought during this slow period of sitting in front of this computer, Let me recreate the scenario I imagine.

Barn is fed from house panel,... new SO cord from house panel feeds barns sub panel which runs above soil. ...You bonded the ground and neutral together at the sub panel, ...you put an amp probe on the ground and got a 3A reading you got a 6A reading on the neutral both separately measured at the home panel side of this new SO cable. ...You then removed or isolated the sub panel ground/neutral bond and turned on some additional loads within the barn, went back to house panel then remeasured the same ground and neutral of the new SO cable to now find 8A on the neutral and 2A on the ground ... I'd suggest that there is stray voltage from a branch circuit in the barn sending 2 amps ( 240w ) back on the barn ground within the barn sub panel which is getting measured with the amp probe over at the house ground wire of the new SO cord. ... just a thought.

Do continuity check between neutral and EGC at the barn to make sure there is no unintentional N_G bond somewhere else in the barn. Other conductive paths between the two buildings can carry current, though it should have opposite effect of what was noticed here.