Panel grounding

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#1

Originally Posted By: kmcmahon
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If a panel is not properly grounded, will the outlets show “open ground”?


I just did an inspection where I swear I could not find a ground wire coming into the panel to ground the panel, however, all out the outlets showed proper ground.

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#2

Originally Posted By: Joey D’Adamo
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My guess is the bonding screw that bonds the neutral bus bar to the chassis of the panel and thus the ground bus bar is providing the path to ground through the neutral service wire.


There really should be a grounding wire to a ground rod or water pipe; if it's missing then although it still works it's not correct.

#3

Originally Posted By: Greg Fretwell
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You don’t have a tester that can verify the quality of the grounding electrode. All your tester is telling you is that the equipment grounding conductor is bonded to the service neutral. That will certainly clear a fault from the line to the grounding conductor but it may not protect you from surges and transients. It can also cause problems where the equipment ground might not be at the same potential as the concrete floor or the dirt outside. For most inspectors the actual grounding of the service will be a visual inspection.

#4

Originally Posted By: Ryan Jackson
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Greg, I don’t think he is talking about the grounding electrode. From the original post:
Quote:
I swear I could not find a ground wire coming into the panel to ground the panel


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Ryan Jackson, Salt Lake City
#5

Originally Posted By: Greg Fretwell
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Ryan Jackson wrote:
Greg, I don't think he is talking about the grounding electrode. From the original post:
Quote:
I swear I could not find a ground wire coming into the panel to ground the panel


Isn't that the GEC he thinks he is missing?
#6

Originally Posted By: jmcginnis
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Yes, your tester will still show ground because the grounded conductor (neutral) is connected back to the xformer from the panel ground/neutral bar… by the way, the grounded conductor (neutral) for the service is also grounded out at the xformer at the base of the power pole. The little plug in testers are far from fool proof. I have seen situations where someone jumpered the green screw (ground) on the receptacle to the silver screw (neutral) to fool the inspector’s tester into showing a correct circuit.

#7

Originally Posted By: kmcmahon
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I wasn’t using a three prong tester, I had a suretest. Same principal though I would guess.

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Wisconsin Home Inspection, ABC Home Inspection LLC


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#8

Originally Posted By: lfranklin
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I don’t think its right.


Here what I am seeing in my mind from the question.


Service entrance to meter, from meter to panel three wires H-H-N,also from meter a ground to the ground rod.

Now at the panel there is only the H-H-N no signs of the GEC except for feeding through the neutral through the meter.

Have I got the wrong pitcher? or just lost?

#9

Originally Posted By: Greg Fretwell
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The service can be grounded at any point from the service disconnect to the customer side of the service point. It is legal and somewhat common to see the GEC connected in the meter base, not in the service disconnect enclosure.

#10

Originally Posted By: jtedesco
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Greg Fretwell wrote:
The service can be grounded at any point from the service disconnect to the customer side of the service point. It is legal and somewhat common to see the GEC connected in the meter base, not in the service disconnect enclosure.


Greg:

In Florida -- this may be common, but in other areas around the country, the GEC is run into the Main Disconnecting Means.

People have mentioned the lightning strikes in Florida as a good reason for the GEC to be installed and "accessible" in the meter socket enclosure.

The rule also allows the GEC to be run up to and connected to the grounded conductor at the drip loop, but I have not seen that in my lifetime yet, and who would want to use another 8-15 feet or more of copper wire anyway.

![icon_surprised.gif](upload://57CELbNgOav4I8DdysEp4jSUiyx.gif)

--
Joe Tedesco, NEC Consultant

www.nachi.org/tedescobook.htm
#11

Originally Posted By: kmcmahon
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lfranklin wrote:
I don't think its right.
Here what I am seeing in my mind from the question.

Service entrance to meter, from meter to panel three wires H-H-N,also from meter a ground to the ground rod.

Now at the panel there is only the H-H-N no signs of the GEC except for feeding through the neutral through the meter.

Have I got the wrong pitcher? or just lost?


That is the correct picture except for the part about from meter a ground to to ground rod. That part I did not see.

It was an underground service.

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Wisconsin Home Inspection, ABC Home Inspection LLC

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#12

Originally Posted By: lfranklin
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Was there two conduits going to the meter? one small & one larger


My guess is the ground is in the smaller one. The service in the larger.

#13

Originally Posted By: Greg Fretwell
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It is very common to see the EGC in the meter base here. They then bring 3 wires into the service disconnect enclosure via a PVC nipple to avoid parallel paths and split out the ECG from there after the bonding jumper. It must be a bit more common than we would think since NFPA has amssaged this language a couple times in the last 2 code cycles.


I agree you are probably not going to see this connection made anywhere except the meter base or the service disconnect but if it was accessible it could be other places on the service entrance cable.


The only other place I do remember seeing it was in a gutter where the service entrance was tapped to grouped disconnects.