Transition of Non Metallic to Metallic Raceway

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csully12

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I have an instance where I have a fiberglass conduit run of approximately 500'. In the middle of the run I have to install a piece of RMC to accomodate a bend that can't be done in fiberglass. The RMC will be exposed near a catwalk. Has anyone run into this and what is the proper way to bond this section of raceway? Thanks for your help in advance.
 
Hopefully someone else can help with the fitting required to make the transition as I have had no experience with fiberglass ducts but one suggestion for bonding of the RMC sections could be a bonding bushing attached to the equipment grounding conductor or grounded conductor if it's service conductors.

Pete

p.s. welcome to the forum
 
csully12 said:
I have an instance where I have a fiberglass conduit run of approximately 500'. In the middle of the run I have to install a piece of RMC to accomodate a bend that can't be done in fiberglass. The RMC will be exposed near a catwalk. Has anyone run into this and what is the proper way to bond this section of raceway? Thanks for your help in advance.
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Is the catwalk part of the Grounding Electrode System by being connected to the building steel? If so, use a bond bushing or a ground clamp on the RMC and run a jumper over to the catwalk.
 
walkerj said:
Is the 90 in between two pieces of fiberglass?
If so, I see no way to bond it compliantly.
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You'd have to run an EGC from someplace where an EGC exists, and use a pipe clamp around the outside of it. Ugly, but that's the only way I know about. I'd rather see this guy use RNC instead of RMC, and that would solve this bonding puzzle.
 
mdshunk said:
You'd have to run an EGC from someplace where an EGC exists, and use a pipe clamp around the outside of it. Ugly, but that's the only way I know about. I'd rather see this guy use RNC instead of RMC, and that would solve this bonding puzzle.
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I know it would work, but is that a compliant way of bonding it?
Just curious for future endeavors.
 
mdshunk said:
You'd have to run an EGC from someplace where an EGC exists, and use a pipe clamp around the outside of it. Ugly, but that's the only way I know about. I'd rather see this guy use RNC instead of RMC, and that would solve this bonding puzzle.
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Exactly!!!!!!!!!!!
 
mdshunk said:
You'd have to run an EGC from someplace where an EGC exists, and use a pipe clamp around the outside of it. Ugly, but that's the only way I know about....
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Not to pick on Marc , but I don't think this is a compliant way to ground this per 250.132/134
 
This is funny, 250.86 exception # 2 allows short sections of raceways used for support or protection not to be connected to the egc, but if its a metal elbow it has to be.(250.86 excpt # 3)
 
Thought I would paste this picture .Not exactly what is being discussed but I thought I would post it regardless.

1113923428_4.jpg
 
M. D. said:
I'm still wondering how this isolated metal is going to be attached to an EGC???
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If there is an EGC installed within the raceway (making an assumption:smile:) then a bonding bushing could be utilized if the GRC terminates at an enclosure.

Pete
 
Thanks for all the responses. There is a ground conductor inside the conduit. I believe what we are going to do is bond the section of RMC to building steel via ground clamps. Both ends of the section of RMC will be bonded. It is a 15kV circuit and I don't want to rely on one connection. The substation where the cicuit is feed from is tied to the building steel. Running an EGC along the outside of the conduit run will only cause futeure problems. This installation is inside a large industrial manufacturing facility that has large bay doors that open directly into a slat water environment.
 
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