bonding bushing at disconnect

[Cjmccarthy]

The conduit that the arrow is pointing to does not have a grounding bushing in the disconnect, the contractor said it was on the other end. The conduit transitions to PVC 6 inches below grade. My question is, does it matter what side the grounding/bonding bushing is located? The rigid conduit in question houses the ground/bounding wire to the ground array. I attached a close up of the disconnect and a typical site layout.

 

[letgomywago]

I think that'd need one where visible is it aluminum rigid by chance

 

[Cjmccarthy]

I think that'd need one where visible is it aluminum rigid by chance

it is RGS, Rigid Galvanized Steel.

 

[Strathead]

The conduit that the arrow is pointing to does not have a grounding bushing in the disconnect, the contractor said it was on the other end. The conduit transitions to PVC 6 inches below grade. My question is, does it matter what side the grounding/bonding bushing is located? The rigid conduit in question houses the ground/bounding wire to the ground array. I attached a close up of the disconnect and a typical site layout.

If you have locknuts inside and outside and you aren't in a concentric/eccentric knockout, or the hole is listed for the use as bonding, then you don't need a bonding bushing per code. I'd be that FDOT specs require one though. Also the person who told you the bushing on the other end, with PVC in between, should be docked a paycheck for stupidity.

 

[Cjmccarthy]

If you have locknuts inside and outside and you aren't in a concentric/eccentric knockout, or the hole is listed for the use as bonding, then you don't need a bonding bushing per code. I'd be that FDOT specs require one though. Also the person who told you the bushing on the other end, with PVC in between, should be docked a paycheck for stupidity.

My mistake, because it houses the ground wire it does not have the PVC pipe in the ground. the RGS stops and the wire is direct bury.

 

[Strathead]

My mistake, because it houses the ground wire it does not have the PVC pipe in the ground. the RGS stops and the wire is direct bury.

so by bushing on the other end, he means on the buried end of the GRC? I doubt a ground bushing is listed for direct burial.

 

[Jpflex]

If you have locknuts inside and outside and you aren't in a concentric/eccentric knockout, or the hole is listed for the use as bonding, then you don't need a bonding bushing per code. I'd be that FDOT specs require one though. Also the person who told you the bushing on the other end, with PVC in between, should be docked a paycheck for stupidity.

I thaught bonding bushings were required only for services or for cabinet entrances containing conductors with voltage of 277 volts or over 150 volts to ground.

Also aren’t you required to knock out all eccentric KOs before selecting reducing washers to the desired size conduit entering a cabinet?

 

[jaggedben]

I thaught bonding bushings were required only for services or for cabinet entrances containing conductors with voltage of 277 volts or over 150 volts to ground.

It's actually just over 250 volts to ground.

Also aren’t you required to knock out all eccentric KOs before selecting reducing washers to the desired size conduit entering a cabinet?

No.

 

[jaggedben]

The code actually does not say anything about reducing washers or concentric/eccentric knock-outs unless the connection is at the service or over 250 volts to ground. It does require removing paint to use connection as a bonding connection, which is relevant to using reducing washers on an outdoor enclosure. A grounding bushing is imo a good practice outdoors.

 

[augie47]

UL: QCRV
GROUNDING Metal reducing washers are considered suitable for grounding for use in circuits over and under 250 V and where installed in accordance with ANSI/NFPA 70, ‘‘National Electrical Code,’’ for raceways containing other than service conductors. Reducing washers are intended for use with metal enclosures having a minimum thickness of 0.053 in. Reducing washers may be installed in enclosures provided with concentric or eccentric knockouts, only after all of the concentric and eccentric rings have been removed. However, those enclosures containing concentric and eccentric knockouts that have been certified for bonding purposes may be used with reducing washers without all knockouts being removed.

 

[Dusty Steele]

I have a question regarding the "required" use of conduit bonding bushings. I have an inspector that is saying all conduits 1 -1/2" and larger are required to have bonding bushings installed and used. He hasn't referenced a code article but, is adamant that they are a code requirement and are to be installed (the installations are not installed in a classified locations). We've installed 27 of the same installations and they have been approved without incident. Not to mention I can't locate a code article that requires them to be utilized. Please advise.

 

[letgomywago]

What's the voltage to ground? Nec doesn't specify anything about the conduit size as to If a bond bushing is required. It's dependant on the reason and then any metalic conduit of any size in that situation requires it.

 

[jaggedben]

I have a question regarding the "required" use of conduit bonding bushings. I have an inspector that is saying all conduits 1 -1/2" and larger are required to have bonding bushings installed and used. He hasn't referenced a code article but, is adamant that they are a code requirement and are to be installed (the installations are not installed in a classified locations). We've installed 27 of the same installations and they have been approved without incident. Not to mention I can't locate a code article that requires them to be utilized. Please advise.

He's just completely wrong.

 

[JJWalecka]

UL: QCRV
GROUNDING Metal reducing washers are considered suitable for grounding for use in circuits over and under 250 V and where installed in accordance with ANSI/NFPA 70, ‘‘National Electrical Code,’’ for raceways containing other than service conductors. Reducing washers are intended for use with metal enclosures having a minimum thickness of 0.053 in. Reducing washers may be installed in enclosures provided with concentric or eccentric knockouts, only after all of the concentric and eccentric rings have been removed. However, those enclosures containing concentric and eccentric knockouts that have been certified for bonding purposes may be used with reducing washers without all knockouts being removed.

are all enclosures certified for bonding purposes?

 

[letgomywago]

are all enclosures certified for bonding purposes?

Pvc isn't. Most panelboards enclosures the eccentrics aren't. The eccentrics on 4 squares and 4 11/16th yes those are usually

 

[Dusty Steele]

He's just completely wrong.

I thought so too. was just looking for an unbiased point of view, Thank You.

 

[mjd1]

250.64 E(1) ?

 

[jaggedben]

250.64 E(1) ?

That's about grounding electrode conductors, which haven't been brought up in this thread.

 

[don_resqcapt19]

are all enclosures certified for bonding purposes?

The only enclosures that have the concentric or eccentric KOs listed for bonding and grounding without all of the rings removed are metal outlet boxes...in general the boxes in 314.16. It is part of the listing requirement for those types of boxes so they are all suitable for the purpose even if the box or container is not so marked, as the listing standard permits but does not require the marking.
There are no disconnect enclosures, panelboard enclosures, or junction boxes that have these types of KOs listed for grounding and bonding.

 

[jaggedben]

...
There are no disconnect enclosures, panelboard enclosures, or junction boxes that have these types of KOs listed for grounding and bonding.

But neither does the code require them to be listed, AFAIK.