WHAT IS WRONG IN THIS PICTURE?

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If whoever did the plans put this bonding conductor on the plans, and your contract calls for you to follow the plans, then doesn't really matter whether it's required by code or not, it's required by your contract.

There's nothing that says that your contract can't require something that's not required by the code. For instance, the code does not require painting conduit, but your contract could require it.
 
kwired said:
Both services must connect to one common GES

I thin the real question is whether you can use the CEE itself as a bonding jumper in this situation or if that jumper in the image is actually required
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"Both services must connect to one common GES"
They already do that, without the "jumper"

"I thin the real question is whether you can use the CEE itself as a bonding jumper in this situation or if that jumper in the image is actually required"
Agree. That is the real question that many seem to have.
Each service has it's own GEC going down to the CEE, therefore code is satisfied.
No "jumper" is required between two different services on a building.
In fact, there is a code that prohibits it. Gold Digger almost touched on it back in post 3.
 
I’m still not sure 230.2 allows this..
Not enough information.
 
One building should have one service. If two services are approved for whatever reason there must be a common ground. If there was not the phase and neutral conductor could operate on slightly different potential. Yes some equalization currents will flow although without the common ground they would flow anyway, and in absence of a solid path most likely through the communication wiring (I mean who is going to tell the IT guy down the road not to run com cables from one part of the building to the other.) I have seen it before.
 
Hv&Lv said:
I’m still not sure 230.2 allows this..
Not enough information.
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If a single occupancy building probably not. If one "service" is feeding a fire pump or any the other items listed in (A), that would be allowed. Had each service been coming from a separate source then it very possibly can be allowed. Kind of is not the main topic of the thread either though, so we kind of are presuming it is allowed under some condition in 230.2.
 
Arester said:
One building should have one service. If two services are approved for whatever reason there must be a common ground. If there was not the phase and neutral conductor could operate on slightly different potential. Yes some equalization currents will flow although without the common ground they would flow anyway, and in absence of a solid path most likely through the communication wiring (I mean who is going to tell the IT guy down the road not to run com cables from one part of the building to the other.) I have seen it before.
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Ethernet signals are isolated from ground anyway so what difference would it make?
 
petersonra said:
Ethernet signals are isolated from ground anyway so what difference would it make?
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There used to be, and probably still are, data and analog signal methods in use that do involve a grounded shield or other conductor. Simple cable TV connections are an ongoing source of problems when a ground offset exists.
 
petersonra said:
Ethernet signals are isolated from ground anyway so what difference would it make?
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I said com (communication cables). Isolation in ethernet does exist but it is week. A lightning strike on some less significant transient event on one side of the building, without equipotential plane for the entire building would breach any isolation in communication systems. That is why a concept of equipotential plane is typically enforced nowadays.
 
Arester said:
I said com (communication cables). Isolation in ethernet does exist but it is week. A lightning strike on some less significant transient event on one side of the building, without equipotential plane for the entire building would breach any isolation in communication systems. That is why a concept of equipotential plane is typically enforced nowadays.
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Equipotential plane in NEC is primarily a topic in art 547 and 680 and is for lessening touch potential between conductive objects. Even those situations could have temporary potential differences in lightning strike events though the arrangement would lessen the effects compared to if there wasn't such bonding.
 
kwired said:
Equipotential plane in NEC is primarily a topic in art 547 and 680 and is for lessening touch potential between conductive objects. Even those situations could have temporary potential differences in lightning strike events though the arrangement would lessen the effects compared to if there wasn't such bonding.
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Correct, NEC primary concern is life safety. Building owners though are also concerned about facility operation, possible damage to equipment and contractors do care about liability that maybe argued if installation fails to follow basic principles of electrical installation. Recommend reading MIL-HDBK-217F published in 1990
 
Arester said:
Correct, NEC primary concern is life safety. Building owners though are also concerned about facility operation, possible damage to equipment and contractors do care about liability that maybe argued if installation fails to follow basic principles of electrical installation. Recommend reading MIL-HDBK-217F published in 1990
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Arester said:
I said com (communication cables). Isolation in ethernet does exist but it is week. A lightning strike on some less significant transient event on one side of the building, without equipotential plane for the entire building would breach any isolation in communication systems. That is why a concept of equipotential plane is typically enforced nowadays.
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Yes NEC primary concern is life safety and property safety - primarily from fires.

I don't ever see any kind of enforcement for such protection for communication systems though it maybe is good design practice.

In fact when it comes to guys that only install communications circuits, I see them not doing things that I been taught was good practices. Most them are clueless on how to install cabling (seriously, seen many easy to fish things that they instead will surface mount and make it ugly because they have no idea how to run cables) and only know how/where to connect items and set up software. I even drilled holes for one guy in a rough in situation. He only had smaller bits for single cable or two to fit through the hole.
 
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