Here goes my first post:
Problem: AmerenUE and Local Fire District together since January 2006 have been trying to bring the docks at the Lake of the Ozarks up to NEC 2005 code as they are installed new or modified in place.
Numerous docks have existing feeders from service panel to onshore subpanel that are 3 wire only, 2 ungrounded conductors and 1 grounded conductor. The local ordinance is being enforced as docks are upgraded, moved or new installations. One of the items the local ordinance requires a minimum upgrade of a grounding electrode 1/2" x 8', and grounding electrode conductor of #6 copper to a grounding busbar that is seperated from the grounded busbar. The dock ramp, dock and all hinged points are bonded together back to the grounding electrode at the seawall.
So you have 3 wire feeder on a 100 to 200 amp subpanel at the seawall with a grounding electrode and conductor to subpanel from electrode, but no grounding conductor back to the service.
If the grounding busbar and grounded busbar are not bonded together will this clear a ground fault?
If they are bonded together do you now have a paralled paths on the dock?
Yesterday (for years on some docks) the existing 200 amp 3 wire subpanel was used and now it is not acceptable or is it?
The first item on the AHJ is there shall be 4 wire ran to subpanels. But since no grounding conductor was ran, but it is my understanding that 250.32 (B)2 doesn't apply even though from service to subpanel is in PVC the dock being all metal frame work is a possible parallel path when bonded as required.
I have several pictures but don't a place to post them.
Diagrams and Documents of AHJ additions can found at:
http://www.ameren.com/Environment/ADC_DockElectrInstal.asp
Steve at the Lake.
Problem: AmerenUE and Local Fire District together since January 2006 have been trying to bring the docks at the Lake of the Ozarks up to NEC 2005 code as they are installed new or modified in place.
Numerous docks have existing feeders from service panel to onshore subpanel that are 3 wire only, 2 ungrounded conductors and 1 grounded conductor. The local ordinance is being enforced as docks are upgraded, moved or new installations. One of the items the local ordinance requires a minimum upgrade of a grounding electrode 1/2" x 8', and grounding electrode conductor of #6 copper to a grounding busbar that is seperated from the grounded busbar. The dock ramp, dock and all hinged points are bonded together back to the grounding electrode at the seawall.
So you have 3 wire feeder on a 100 to 200 amp subpanel at the seawall with a grounding electrode and conductor to subpanel from electrode, but no grounding conductor back to the service.
If the grounding busbar and grounded busbar are not bonded together will this clear a ground fault?
If they are bonded together do you now have a paralled paths on the dock?
Yesterday (for years on some docks) the existing 200 amp 3 wire subpanel was used and now it is not acceptable or is it?
The first item on the AHJ is there shall be 4 wire ran to subpanels. But since no grounding conductor was ran, but it is my understanding that 250.32 (B)2 doesn't apply even though from service to subpanel is in PVC the dock being all metal frame work is a possible parallel path when bonded as required.
I have several pictures but don't a place to post them.
Diagrams and Documents of AHJ additions can found at:
http://www.ameren.com/Environment/ADC_DockElectrInstal.asp
Steve at the Lake.
