250.53(C) vs. 250.102(C)

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George Stolz

George Stolz

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Look at the following one line, and tell me, does the bonding jumper between the building steel and water pipe have to be 4/0 or 3/0 CU?
 

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George Stolz said:
Is the conductor between the steel and the water pipe a Supply Side Bonding Jumper? :)
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I think this question is in reference to Bonding Jumper, Main (at the service).
not, Bonding Jumper, System (separately derived system)..........but I think you knew that....:+).


SSBJ.........................any relation to sbir or lbir ?
answer:no
 
Ritelec, do you see anything in the definition of "Supply Side Bonding Jumper" to exclude the conductor depicted between the steel and the water pipe in the diagram?

The conductor between the steel and the water pipe is clearly not a Main Bonding Jumper or a System Bonding Jumper.
 
George Stolz said:
Ritelec
Click to expand...


You can call me Rich.

"do you see anything in the definition of "Supply Side Bonding Jumper" to exclude the conductor depicted between the steel and the water pipe in the diagram"?

no. The utility x former is a separately derived system also. but it's service??? Would not the conductor between the beam and water pipe be part of the grounding electrode system (conductor)?

"The conductor between the steel and the water pipe is clearly not a Main Bonding Jumper or a System Bonding Jumper".

Wait........I may be seeing what your getting at........jumper vs conductor.

In answer to your questions..........I haven't.

working on it....bonding conductor or jump... a conductor that insures electrical conductivity between metal parts of the electrical installation.
 
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ritelec said:
You can call me Rich.
Click to expand...
Thanks. :)

Do you see anything in the definition of "Supply Side Bonding Jumper" to exclude the conductor depicted between the steel and the water pipe in the diagram?
Click to expand...

no. The utility x former is a separately derived system also.
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No, it is a service.

Would not the conductor between the beam and water pipe be part of the grounding electrode system (conductor)?
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Yes, that's it's reason for being installed, 250.50.

The conductor between the steel and the water pipe is clearly not a Main Bonding Jumper or a System Bonding Jumper.
Click to expand...

Wait........I may be seeing what your getting at........jumper vs conductor.
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Not so much. What I am getting at is that 250.53(C) states that we follow 250.66, but 250.102(C) requires us to size a large conductor to 12.5% of the ungrounded conductors. The question is, is that conductor between the steel and the water pipe a supply side bonding jumper? I think there is a goof in the definition of Supply Side Bonding Jumper.
 
George Stolz said:
What I am getting at is that 250.53(C) states that we follow 250.66, but 250.102(C) requires us to size a large conductor to 12.5% of the ungrounded conductors. The question is, is that conductor between
the steel and the water pipe a supply side bonding jumper? I think there is a goof in the definition of Supply Side Bonding Jumper.
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crazy...So in 250.66...........instead of over 1100 - 3/0.....why don't they continue the chart or refer you to 250.102c to make it the 12.5% .......thank you for bring this to my attention.(or does 250.102c come into play after the service? At the service 3/0 is the max?)


Or am I reading this wrong and there is grounding electrode conductor which would max a 3/0, but there's a SSBJ also which could be sized larger then the GEC.

I gotta work on this.


The question...........Is the steal to water pipe a supply side bonding jumper...............I'm going to say no.... it's a grounding electrode conductor.

I think if the utility x former in the picture was a custom transformer......the grounding between that transformer and disconnect would be SSBJ...................

let me know please.......right or wrong.
 
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Thank you Dave,

So, from the steal to water, is it a grounding electrode bonding jumper?

Is it a system bonding jumper?

Is it a supply side bonding jumper?



wowe..................getting real close to just calling it a wire.

So from the neutral to steal it's a conductor (gec) but from steal to water its a jumper (sbj)?
If it were continuous (the wire) from neutral to steal to water pipe, is it still a jumper from steal to water or part of the conductor?
 
ritelec said:
wow..................getting real close to just calling it a wire.

So from the neutral to steal it's a conductor (gec) but from steal to water its a jumper (sbj)?
If it were continuous (the wire) from neutral to steal to water pipe, is it still a jumper from steal to water or part of the conductor?
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I'm going with "Bonding Jumper". My opinion, it's a GEC to the first electrode and bonding jumper after that be it continuous or spliced.
 
ActionDave said:
A Supply Side Bonding Jumper bonds together metal parts that contain service conductors, say, four sets of RMC coming into an open bottom cabinet at a service.
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I understand what the intent probably was, but don't you think the wording is kind of wide open?

Bonding Jumper, Supply-Side. A conductor, like, installed on the supply side of a service or within a service equipment enclosure(s), or for a separately derived system or somethin', that ensures the required electrical conductivity between metal parts required to be electrically connected and stuff.
Click to expand...

;)
 
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