OT ELECTRICAL QUESTION

[bc]

I hope not I try my best to help but I’m headed to the festival stage now for fun relaxation and entertainment may pick my old banjo later.

John T

Must be the Winding Creek Music Festival. Are you in one of these bands?

Bluegrass music that's where it's at, let's here it for Lester Flatt.

Winding Creek music festival bands

 

[John T]

Must be the Winding Creek Music Festival. Are you in one of these bands?

Bluegrass music that's where it's at, let's here it for Lester Flatt.

Winding Creek music festival bands

Yep im at winding creek in Russiaville Indiana havin a fun but wet today time. No way I’m band material just pick a bit at open jams in my senior years. Just heard the Baker Family wow are they good

More fun than old tractors

John T

 

[bc]

Yep im at winding creek in Russiaville Indiana havin a fun but wet today time. No way I’m band material just pick a bit at open jams in my senior years. Just heard the Baker Family wow are they good

More fun than old tractors

John T

Can't find the name of the song for the lyric I quoted but it was by John Hartford.

 

[Copperhead don't play]

John T, You said earlier that
"There must be only one neutral ground bond.
That’s why if it’s a sub panel fed from the main where the bond has already been established you do nottttt bond again and n and g are isolated and insulated from each other. Well duh lol"

I don't understand. If I connect a conductivity meter test at the main panel neutral and the ground in the sub panel will they not show conductivity?

 

[olddavid]

John T, You said earlier that
"There must be only one neutral ground bond.
That’s why if it’s a sub panel fed from the main where the bond has already been established you do nottttt bond again and n and g are isolated and insulated from each other. Well duh lol"

I don't understand. If I connect a conductivity meter test at the main panel neutral and the ground in the sub panel will they not show conductivity?

Yes it will. Somewhere the two are connected together. Either at the main panel or if there is a disconnect breaker panel at the meter they will be connected together there. But the sup panel is supposed to have a separate neutral and ground ran to it. That's just the way it is under the new code.

 

[John T]

John T, You said earlier that
"There must be only one neutral ground bond.
That’s why if it’s a sub panel fed from the main where the bond has already been established you do nottttt bond again and n and g are isolated and insulated from each other. Well duh lol"

I don't understand. If I connect a conductivity meter test at the main panel neutral and the ground in the sub panel will they not show conductivity?

Yes and they better be !!! If bonded at the main snd the conductors are good and intact the resistance should be very low between n and g in the subs. Neutral is a live current carrying insulated conductor so it’s not in contact with you or the appliance case while the EGC is often bare and in contact with the metal case frame of tools you touch and doesn’t carry current unless there’s a fault.

Good question copper you’re getting there it’s just I’m no teacher but do try my best

John T

 

[stevieb49829]

John T and the Rest of Youse: not based on code, but on common sense, why only one bonded pathway? Does it screw up the safety somehow if the sub is bonded also? Steve

 

[stevieb49829]

"then there are two parallel paths for hot live current and remrmber where the ground conductor colud perhaps be attached"
That triggered the understanding for me, John. That if you tie them together somewhere remote, you are making a potentially uninsulated conductor into a hot lead.
Now go back to your bluegrass!! steve

 

[John T]

John T and the Rest of Youse: not based on code, but on common sense, why only one bonded pathway? Does it screw up the safety somehow if the sub is bonded also? Steve

Good question. Actually the reason for only one n g bond is both for safety as well as common sense plus sound engineering. N is a hot live current carrier that’s insulated, you don’t went to touch it for risk of electrocution. The ground is bare and in contact with outer case frames of tools you touch and is not carrying live current and safe to touch tools and appliances. If you tie them together again later downstream from the mains n g bond then there are two parallel paths for hot live current and remrmber where the ground conductor colud perhaps be attached !!!! You wouldn’t touch the hot live neutral under its insulation would you and you wouldn’t want to touch the ground if it became a hot live current carrier. Ground is only for fault current while n is normal hot live current conductor so don’t mix n match and tie them together in parallel again downstream of the main and its sole n g bond. This is very very basic in the nec snd known by electricians since day one of training so don’t feel bad if a lay person gets confused that’s only normal and to be expected same as a non plumber or non carpenter May but understand those basics.

Even if one doesn’t understand it look in the nec or a basic electricians text and do your own research to see the safety and common sense and reasons for only one n g bond.

That’s the best I can do don’t take my word for it consult trained professional engineers and electricians about grounds and neutrals and bonding etc etc. it gets complicated for non sparkies which is to be expected and normal.

Best wishes do as you please but be safe out there with electricity as it can prevent a fire or save a life

Ground is only for fault current and bonded to tools appliances and cases of many devices while neutral is an insulated live conductor so you don’t touch it snd risk a shock so don’t mix n match or substitute n and g I hope this helps but if not I tried my best

Yes as you asked it screws up the safety if done wrong !!!!!!!!!!

ps this is not perfect or exact or correct 100% and can’t be put in a few sentences what takes volumes snd experience to comprehend so take or leave it at your own risk no warranty I’m only trying to help and answer your questions that’s the best this old long retired farmer engineer and attorney can do

John T

 

[John T]

"then there are two parallel paths for hot live current and remrmber where the ground conductor colud perhaps be attached"
That triggered the understanding for me, John. That if you tie them together somewhere remote, you are making a potentially uninsulated conductor into a hot lead.
Now go back to your bluegrass!! steve

Glad I helped it took some time but I’m still glad you’re getting it now. It was worth it and time well spent. We’re all neighbors helping each other yayyyy

John T

 

[drsportster]

Exactly correct my old sparky electrician friend as the basic cardinal rule for sound and safe reasons sparkies understand is. There must be only one neutral ground bond.

That’s why if it’s a sub panel fed from the main where the bond has already been established you do nottttt bond again and n and g are isolated and insulated from each other. Well duh lol

Take care maybe see you when in Florida.

John T

Hope to see you to John

 

[Copperhead don't play]

Thank you, John T,
I now understand why they are bonded at the main and not again at the sub. You have explained it very well. I thought I was the only one who did not understand the reason.
Thanks Again.

 

[John T]

Thank you, John T,
I now understand why they are bonded at the main and not again at the sub. You have explained it very well. I thought I was the only one who did not understand the reason.
Thanks Again.

Youre welcome glad I helped

John T

 

[olddavid]

Good question. Actually the reason for only one n g bond is both for safety as well as common sense plus sound engineering. N is a hot live current carrier that’s insulated, you don’t went to touch it for risk of electrocution. The ground is bare and in contact with outer case frames of tools you touch and is not carrying live current and safe to touch tools and appliances. If you tie them together again later downstream from the mains n g bond then there are two parallel paths for hot live current and remrmber where the ground conductor colud perhaps be attached !!!! You wouldn’t touch the hot live neutral under its insulation would you and you wouldn’t want to touch the ground if it became a hot live current carrier.

Thanks John. I take one little exception to your explanation. You CAN touch a bare neutral and not get shocked. Since the neutral is at ground potential there is no voltage on it. The same is true for the ground wire even if it is conducting current from a faulty unit to ground. A neutral WILL be hot however if it gets disconnected somehow from the power line ground since voltage will feed through whatever is connected to it to the neutral wire. Please don't ask me how I found that out.

 

[bc]

Thanks John. I take one little exception to your explanation. You CAN touch a bare neutral and not get shocked. Since the neutral is at ground potential there is no voltage on it. The same is true for the ground wire even if it is conducting current from a faulty unit to ground. A neutral WILL be hot however if it gets disconnected somehow from the power line ground since voltage will feed through whatever is connected to it to the neutral wire. Please don't ask me how I found that out.

I'm wondering here. Are you talking about touching the neutral with no shock at the panel or somewhere downstream such as a light bulb socket? I was the inquisitive little kid who stuck his finger in a light socket. From working on a/c units, I can tell the difference between a 120 volt shock and the jolt from 240v. I always have testers around along with insulated tools and fiberglass ladders. Wearing tennis shoes helps there as well and especially while working around electric fences.

 

[bc]

Good question. Actually the reason for only one n g bond is both for safety as well as common sense plus sound engineering. N is a hot live current carrier that’s insulated, you don’t went to touch it for risk of electrocution. The ground is bare and in contact with outer case frames of tools you touch and is not carrying live current and safe to touch tools and appliances. If you tie them together again later downstream from the mains n g bond then there are two parallel paths for hot live current and remrmber where the ground conductor colud perhaps be attached !!!! You wouldn’t touch the hot live neutral under its insulation would you and you wouldn’t want to touch the ground if it became a hot live current carrier. Ground is only for fault current while n is normal hot live current conductor so don’t mix n match and tie them together in parallel again downstream of the main and its sole n g bond. This is very very basic in the nec snd known by electricians since day one of training so don’t feel bad if a lay person gets confused that’s only normal and to be expected same as a non plumber or non carpenter May but understand those basics.

Even if one doesn’t understand it look in the nec or a basic electricians text and do your own research to see the safety and common sense and reasons for only one n g bond.

That’s the best I can do don’t take my word for it consult trained professional engineers and electricians about grounds and neutrals and bonding etc etc. it gets complicated for non sparkies which is to be expected and normal.

Best wishes do as you please but be safe out there with electricity as it can prevent a fire or save a life

Ground is only for fault current and bonded to tools appliances and cases of many devices while neutral is an insulated live conductor so you don’t touch it snd risk a shock so don’t mix n match or substitute n and g I hope this helps but if not I tried my best

Yes as you asked it screws up the safety if done wrong !!!!!!!!!!

ps this is not perfect or exact or correct 100% and can’t be put in a few sentences what takes volumes snd experience to comprehend so take or leave it at your own risk no warranty I’m only trying to help and answer your questions that’s the best this old long retired farmer engineer and attorney can do

John T

Yep. And back in the day there were people who were electrocuted using their metal power drills and washing machines.

I might add that under article 250 I believe, that subpanels in detached buildings whether fed by 3 or 4 wires, as long as they are Not bonded like we are discussing here, can have multiple ground rods attached to the subpanel box frame for lightning protection purposes.

I think we have covered about everything a typical farmer might be dealing with at the farm except anyone with an animal or dairy barns needs their local electricians dealing with them as amateurs should stay away from those. The Amish didn't have to worry.

I won't get down deep in the weeds so far as to discuss when a separate disconnect may be needed or the difference between feeder and branch circuits as that gets rather murky.

 

[JMOR]

Thanks John. I take one little exception to your explanation. You CAN touch a bare neutral and not get shocked. Since the neutral is at ground potential there is no voltage on it. The same is true for the ground wire even if it is conducting current from a faulty unit to ground. A neutral WILL be hot however if it gets disconnected somehow from the power line ground since voltage will feed through whatever is connected to it to the neutral wire. Please don't ask me how I found that out.

"Since the neutral is at ground potential there is no voltage on it.". IF you call 3.6 volts "no voltage". EX: 112 feet of 12GA copper carrying 20 amperes will have the neutral at the load, 112 feet from panel, 3.6 volts above earth ground.

 

[John T]

Thanks John. I take one little exception to your explanation. You CAN touch a bare neutral and not get shocked. Since the neutral is at ground potential there is no voltage on it. The same is true for the ground wire even if it is conducting current from a faulty unit to ground. A neutral WILL be hot however if it gets disconnected somehow from the power line ground since voltage will feed through whatever is connected to it to the neutral wire. Please don't ask me how I found that out.

I agree you can touch a bare neutral and not get shocked if its NOT carrying any current HOWEVER if its carrying current,,,,,,,,,,,,you touch it,,,,,,,,,your feet or any body part is in contact with say mother earth or any other return current path,,,,,,,,,YOU ARE PLACING YOUR BODY IN PARALELL WITH A CURRENT PATH AND CURRENT CAN FLOW IN THE AREA OF YOUR HEART AND AS LITTLE AS 0.030 AMPS CAN CAUSE FIBRILLATION

Sooooooooooooo I agree you can strip off the insulation and touch neutral and NOT get shocked,,,,,,,,,,,, but if its carrying current and you put your body in parallel depending on what other body part is in contact with earth or another path, your body can conduct current and YOU CAN GET SHOCKED.

Thanks for the fun chat and sharing your experience, we can agree to disagree on this with all due respect, but I still believe it is possible to get shocked by touching a bare current carrying neutral subject to what else another body part is in contact with I DO NOT RECOMMEND STRIPPING INSULATION OR TOUCHING A BARE NEUTRAL but of course no warranty !!!!!!!!

Heck Im LONG retired and may well be wrong on this and perhaps YOU CANT GET SHOCKED GRABBING A BARE NEUTRAL THATS CARRYING CURRENT but Im still afraid to try and like it being insulated myself. I just dont like the idea of my body being in parallel with a live current carrier IF IM WRONG (you cant get shocked) I WANT TO THANK IN ADVANCE ALL YOU FINE SPARKIES FOR EDUCATING ME yAYYYYYYYYYYYYYYYYYYYYYYYYYY

I figure the neutral is insulated for a darn good reason and I advise do not touch it

Best wishes David i enjoy our sparky chat even if we may disagree on this one lol

John T

 

[John T]

Yep. And back in the day there were people who were electrocuted using their metal power drills and washing machines.

I might add that under article 250 I believe, that subpanels in detached buildings whether fed by 3 or 4 wires, as long as they are Not bonded like we are discussing here, can have multiple ground rods attached to the subpanel box frame for lightning protection purposes.

I think we have covered about everything a typical farmer might be dealing with at the farm except anyone with an animal or dairy barns needs their local electricians dealing with them as amateurs should stay away from those. The Amish didn't have to worry.

I won't get down deep in the weeds so far as to discuss when a separate disconnect may be needed or the difference between feeder and branch circuits as that gets rather murky.

Things may have since changed but when I practiced any buildings (such as remote outbuildings fed with sub panels) electrical service requires grounding so ground rods there are used and required !!!!!!!!!!!!!! How many is another question

I think we basically agree on ground rods at detached buildings are used !!!!!!!!!!!!!!!!

John T

 

[zuhnc]

Ground rods and ground/neutral bonds are two different things. One can have as many ground rods as one wishes.

I do hope the OP, even with all the gerrymandering here, got his original question answered. zuhnc