Is the neutral providing the ground?

[John Kogel]

This panel is in a 1975 condo. I did not have access to the main disconnect, but the service looked to be 200 amp. There are 8 units in the building. I estimated this to be 60 amp service. I have called for repair to correct the grounding.

My question is, if the neutral bus is isolated, appears to be, is grounding achieved by way of the neutral service conductor back to the main disconnect? This had to be wrong even in 1975, right?

Yes, there are 7 breakers, one too many? Well, there is a tie-bar missing. :>)

[Speedy Petey]

Yes, this panel should have an isolated neutral and the neutral not bonded. This is an old installation so who know what went on at the time as far as inspections go.

The seven breakers is not an issue if the main disconnect is somewhere within the same structure.

[John Kogel]

Thanks, SP. I'm wondering if this amounts to a bootleg ground for the whole apartment? There are over 60 units in this complex, BTW.

[Gunnar Alquist]

John,

Can't tell for sure, but it looks like there is a grounding conductor attached to the left side of the panel. If that is true, it would mean that this should be fairly easy to install a grounding terminal block and attach all of the grounding conductors to it.

[Jerry Peck]

Can't tell for sure, but it looks like there is a grounding conductor attached to the left side of the panel. If that is true, it would mean that this should be fairly easy to install a grounding terminal block and attach all of the grounding conductors to it.

Same thing I was looking at ... that starts out at the top where that feeder cable comes through.

Improper grounding terminal, replace with a proper grounding terminal and relocate the grounding conductor to there.

[Corn Walker]

I'm also wondering if that is a bonding screw at the bottom, left of the neutral terminal block. If so, it would need to be removed when the proper grounding bar is installed and connected to that #8 stranded on the left of the enclosure.

[Raymond Wand]

Yes, this panel should have an isolated neutral and the neutral not bonded. This is an old installation so who know what went on at the time as far as inspections go.

The seven breakers is not an issue if the main disconnect is somewhere within the same structure.

Maybe I am missing something but up here in Canada the neutral should have a bonding strap to the panel?

[Jerry Peck]

Maybe I am missing something but up here in Canada the neutral should have a bonding strap to the panel?

Raymond,

Probably only if that panel is also service equipment.

It the panel is a remote panel then the neutral should most likely be isolated from ground.

[Michael Schirmer]

Non-isolated grounds and neutrals are OK, you just can't have them sharing the same taps. Separate the grounds and neutrals under the same termination.
The connection of a neutral and equipment-grounding conductor in the same termination creates an issue and is not an ideal configuration. One of the objectives of the particular arrangement of bonding jumpers, neutrals and equipment grounds is to allow circuit isolation while keeping the equipment grounding conductor still connected to the grounding electrode (see UL 869A -Reference Standard for Service Equipment). When the neutral is disconnected, the objective is to still have the equipment ground solidly connected to the grounding electrode. If both the neutral and grounded conductor is under the same terminal, this cannot be accomplished.
If the screw were loosened by an electrician or became loose, one would lose both the return path for current as well as the fault clearing ability should a hot contact a metallic surface.
E3606.4 Grounded conductor terminations.
Each grounded conductor shall terminate within the panel board on an individual terminal that is not also used for another conductor, except that grounded conductors of circuits with parallel conductors shall be permitted to terminate on a single terminal where the terminal is identified for connection of more than one conductor.

[Jerry Peck]

Non-isolated grounds and neutrals are OK, you just can't have them sharing the same taps. Separate the grounds and neutrals under the same termination.


Michael,

Please clarify your statement.

Are you saying that you do not have to isolate the neutral from ground in all panels?

[Raymond Wand]

Raymond,

Probably only if that panel is also service equipment.

It the panel is a remote panel then the neutral should most likely be isolated from ground.

Thanks Jerry,

The panel in the photo at least to my thinking is the service panel. The 200 amp service in my home for instance has a main disconnect (fused) separate from the service panel. If it where a sub panel then the bonding strap is not required.
The service panel neutral bar is bonded to the service panel. I think this is how it should be in John situation?

Thanks,

[Michael Schirmer]

Michael,

Please clarify your statement.

Are you saying that you do not have to isolate the neutral from ground in all panels?

In this panel.

[bob smit]

No down stream, if u will, grounded conductor and grounding conductor connections.
This is to eliminate 'objectionable current' on grounding conductors and equipment. If this is a sub-distribution panel, then the grounded buss and conductors (may be a neutral) will have to be floating, as the term is used.

If in fact this is service equipment, then the grounded conductor MUST be bonded to the grounding electrode system and all non-current metalic enclosures, equipment, and grounding conductors by means of a 'main bonding jumper' which is sometimes a green colored screw in a panel and/ or a properly sized conductor per table 250.66.

The only exception, would be an ungrounded system or a corner grounded delta where no neutral is dirived or used. There are special rules regarding high impedence applications that is beyond the scope of this thread.
Bob Smit, County Electrical Inspector.

[John Kogel]

Thanks Jerry,

The panel in the photo at least to my thinking is the service panel. The 200 amp service in my home for instance has a main disconnect (fused) separate from the service panel. If it where a sub panel then the bonding strap is not required.
The service panel neutral bar is bonded to the service panel. I think this is how it should be in John situation?

Thanks,This is a condo and the service disconnect is down the hall in the vault with the meters.

[Jerry Peck]

The panel in the photo at least to my thinking is the service panel.


In this panel.

That's why I was clarifying.

I was sure the statements were in relation to the photo, they were just not presented quite that way, which could really be confusing for people who are trying to understand and learn.

[Jerry Peck]

That's why I was clarifying.

I was sure the statements were in relation to the photo, they were just not presented quite that way, which could really be confusing for people who are trying to understand and learn.


This is a condo and the service disconnect is down the hall in the vault with the meters.

John,

Then it IS NOT service equipment, which is what we were thinking it was. Even after you stated in your first post that you "could not have access to the main disconnect". WE really need to read and pay attention better - I know I started off thinking it was not, then switch to thinking it was as I read other posts. :eek:

That means the neutral needs to be isolated from ground.

[Cobra Cook]

The box on the bottom to middle way has a screw that appears to have a copper ground to it, this could be the ground for the box. The white neutral wire appears to be larger than the two hot wires, at the time the condo was wired this was most likely ok for the time. What did your meter or tester show you, was it grounded? If the home is not getting any upgrades to the wiring for the house? If not then it does not have to have any thing as far as electrical done. If anything new is being added then the box will have to be brought up to todays codes and the neutral and ground will have to be seperate. As far as the 7 breaker rule would apply ,the fire department who made that rule would go to the main service cut off so they could turn the power to the building, around here they make inspections to all of the commercial buildings and note in their records to that fact where to kill the power to the building. I do not know why some of you want to equate that a home inspector is a code enforcer, we are not, it does not matter that you may be a nationally approved grand ommpa electrical inspector, when you are doing a home inspection stick to what you were supposed to have been taught at school and what the code of ethics of the home inspectors organization state and finally what national home inspectors exam calls for.

[John Kogel]

The box on the bottom to middle way has a screw that appears to have a copper ground to it, this could be the ground for the box.Yes the panel box is grounded with a bare copper wire coming from the main breaker panel.
What did your meter or tester show you, was it grounded? If the home is not getting any upgrades to the wiring for the house? If not then it does not have to have any thing as far as electrical done. I don't agree. If there is a question as to the quality of the grounding, I will call for repair for safety. I don't care if it meets code requirements, it appears to have been done wrong in 1975. The outlets test grounded, but it is, I think, a bootleg ground by way of the big neutral wire, which is grounded down the hall in the main panel. See what I'm saying?
what national home inspectors exam calls for.What do they say about hazardous wiring? :confused:

[Cobra Cook]

I am not sure about 1975 nec but some time later it was changed to ,The neutral and ground had to be seperated within the panel box. If in your opinion you believe somthing is unsafe in your inspection you are right to make a note of it and that is where you say somthing like recommend having "a licenced electrical contractor to evaluate" I do see somthing in the box that i would check further as it appears to have a double tap on the second or third breaker on the right but, again if the breaker is rated for double tapping then there is nothing wrong with that either. What do you say about when a house has knob and tube wiring? The ground and nuetral in the discussion above would be on the same level. Do you reccomend replacement of that too?

[Jerry Peck]

code wise...4-wire was NEC in 75.

Ben,

What code section are you referring to in the 1975 NEC?

[Raymond Wand]

It would be nice if someone could also quote from the Canadian Electrical Code?

[Jerry Peck]

It would be nice if someone could also quote from the Canadian Electrical Code?

Do you have a link to it?

[Raymond Wand]

Jerry

Unfortunately I do not have a link and my CEC book is from 1992 so its likely outdated, and besides I am not sure I could even find what we are talking about in the 92 version. ;)

[Jerry Peck]

Jeez, Jerry, keep on track will you?

Replying to one when you think you are replying to another?

Criminey.

:D :eek:

[Tony Coelho]

That's why I was clarifying.

I was sure the statements were in relation to the photo, they were just not presented quite that way, which could really be confusing for people who are trying to understand and learn.

Thanks Jerry!!!:)

[Corn Walker]

Okay, I've stared at that panel long enough.

The ground bonded to the enclosure looks to be part of the feeder cable, not a separate grounding conductor. The feeder looks to be #6 stranded, while the ground conductor appears to be #8 stranded. It was not uncommon to have an undersized ground conductor, as appears to be the case on all of the branch circuits as well.

The two prominent problems with the box are:

1) Neutral and ground not isolated in non-service equipment.
2) Multiple conductors in a single terminal.

To remedy these defects one would need to install a separate ground bar and relocate all of the bare grounding conductors to terminals on this bar. The #8 stranded that is currently bonded to the enclosure should also be moved to this bar, which itself would be bonded to the enclosure. If there is a bonding screw on the neutral bus bonding it to the enclosure it should be removed. While I was at it, I would neaten up those wires a bit. I can't stand sloppy panels like that.

[Jerry Peck]

The #8 stranded that is currently bonded to the enclosure should also be moved to this bar, which itself would be bonded to the enclosure.


Why?

It would help if you would identify the conductors are 'groundED', 'groundING', and 'UNgrounded' conductors instead of just "the #8 stranded".

I also suspect that doing that may change what you stated above.

[Corn Walker]

Why?

It would help if you would identify the conductors are 'groundED', 'groundING', and 'UNgrounded' conductors instead of just "the #8 stranded".

I also suspect that doing that may change what you stated above.

That won't change what I stated, but looking at the picture again might.

The "grounded" #8 currently bonded to the enclosure looks like it might be using a proper case grounding lug, in which case it can be left as is (when I originally looked at the picture, I got it in my head that it was not using a proper grounding lug). The grounding bar will need to be bonded to the enclosure - some require a bonding jumper to do so, others are bonded through the mounting screws. The "grounding" conductors of the branch circuits, which are currently improperly "bonded" to the neutral conductors of said circuits, will be properly isolated from the neutral conductors and "grounded" when they are moved to the new grounding bar and the bonding screw, if one is present, is removed from the neutral bar.

[Jerry Peck]

That won't change what I stated, but looking at the picture again might.

The "grounded" #8 currently bonded to the enclosure looks like it might be using a proper case grounding lug, in which case it can be left as is (when I originally looked at the picture, I got it in my head that it was not using a proper grounding lug). The grounding bar will need to be bonded to the enclosure - some require a bonding jumper to do so, others are bonded through the mounting screws. The "grounding" conductors of the branch circuits, which are currently improperly "bonded" to the neutral conductors of said circuits, will be properly isolated from the neutral conductors and "grounded" when they are moved to the new grounding bar and the bonding screw, if one is present, is removed from the neutral bar.


See? Wasn't that a lot easier? :D

[John Kogel]

I do see somthing in the box that i would check further as it appears to have a double tap on the second or third breaker on the right but, again if the breaker is rated for double tapping then there is nothing wrong with that either.Thanks, CC, I looked at it again. there are only 3 black wires on that side, but one is very long and wrapped back up behind the breakers, looking like a 4th wire.
What do you say about when a house has knob and tube wiring? The ground and nuetral in the discussion above would be on the same level. Do you reccomend replacement of that too?Yes, I recommend replacement of K+T, mainly for insurance reasons, but also because people today are ignorant of the dangers of open wiring in their basements and attics.