I am feeding a disconnect for a chiller from a transformer. I am using sched 40 pvc with rigid elbows. At the transformer and the disconnect the elbows are bonded with bond bushings. I have a question regarding the elbow coming up out of the ground feeding the chiller. From the elbow to the chiller cabinet I am using liquid tight conduit. I would think that I need to bond the rigid conduit somehow because I don't believe that the liquid tight conduit is suitable to put a bond bushing on in order to bond the metal elbow. Does anyone have any suggestions?
Rigid elbow bonding
- Thread starter JdoubleU
- Start date
- Status
- Location
- New Jersey
- Occupation
- Journeyman Electrician
If your LFMC is does not qualify as an EGC then you would need some sort of external bonding jumper on the elbow.
Would anyone be able to send me a picture of a clean way of doing this. Maybe I could install a bond bushing on the liquid tight connectors before I install them on the conduit and the chiller cabinet and then run a equipment ground between the two. I believe a standard locknut is all that is required in the chiller cabinet, correct.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Put a ground clamp on the elbow and run an external ground to the other end and tie it to the equipment grounding conductor.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Use a bonding type LFMC connector on the end opposite the elbow and install a bonding jumper from that connector to the elbow.
Carultch
Senior Member
- Location
- Massachusetts
Use a bonding type LFMC connector on the end opposite the elbow and install a bonding jumper from that connector to the elbow.
If that connector is going to be buried, you should swap out the lug with a direct-burial rated lay-in-lug.
In fact, even if it is installed outdoors and not buried, I still recommend doing the same. Direct-burial rated lay-in-lugs are much better at withstanding corrosion.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Does the OP mention that the elbow and transition to LFMC is buried? I was envisioning the elbow sticking out of the ground and the transition point being above grade.
I'm a little lost on OP description also. Is the rigid conduit stubbed out of the ground, changed over to LFMC to an rigid elbow to the chiller? Why would you need a bond bushing? Everything would be "Bonded", although the LFMC is probably not qualified as an EGC in this application, if he has a wire EGC in the conduit I still don't see a need for a Bond Bushing. Unless i'm envisioning the install differently???
- Location
- New Jersey
- Occupation
- Journeyman Electrician
I'm envisioning a run of PVC with a metallic elbow that's emerges from the ground where is changes over to LFMC to the chiller. Since the LFMC does not qualify as an EGC the metallic elbow is not grounded.
If the chiller has an egc that was ran through the PVC to the elbows to the LFMC to another elbow and then the chiller, the the chiller would be grounded along with the elbow, LFMC and then back to the elbow in the ground before it transitions back to PVC. Everything on that side would be bonded and grounded.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
There is the metal elbow between the LFMC on one end of the elbow and PVC on the other end of the elbow. The metal elbow is isolated by two non-EGC's, the PVC raceway and the LFMC which does not qualify as an EGC. Therefore the metal elbow is not properly grounded.
- Location
- Massachusetts
I agree.
Ya, you got a point.
- Status