Just looked at some prints today showing grounding detail for a cell antennea installation.
The detail was, to me, unclear of intent.
It showed a 1? 3W meter off an existing Service which is just a block diagram and a 4 AWG EGC to the multi-story roof top location of the cell equipment.
A Grounding bus, mounted on insulators, with a 4/0 grounding conductor in metal raceway to the water service on the 1st floor level with a 6 AWG Bonding Bushing Bonding Jumper from the metal raceway to the water service at the ground floor end of the metal raceway only.
The other termination points on the rooftop grounding bus is for the various cabinet circuiting grounding.
The details did not show that the 4 AWG EGC with the 1? feeder to the rooftop equipment was to be connected to this Grounding Bus.
That 4/0 is certainly not a GEC. Is bonding jumper size, as per 250.64(E), an NEC requirement?
That 4/0 may be for lightning drain ?
Will be calling the Engineer next week of not showing the 4 AWG EGC not being connected to Isolated from equipment 'Grounding Bus' on the prints.
800.40 will be part of the subject as well as 250.106, 250.60 and 250.58.
Will need to see the existing Service Equipment to see how it is grounded. It is one floor down from the roof level.
gwz2
The detail was, to me, unclear of intent.
It showed a 1? 3W meter off an existing Service which is just a block diagram and a 4 AWG EGC to the multi-story roof top location of the cell equipment.
A Grounding bus, mounted on insulators, with a 4/0 grounding conductor in metal raceway to the water service on the 1st floor level with a 6 AWG Bonding Bushing Bonding Jumper from the metal raceway to the water service at the ground floor end of the metal raceway only.
The other termination points on the rooftop grounding bus is for the various cabinet circuiting grounding.
The details did not show that the 4 AWG EGC with the 1? feeder to the rooftop equipment was to be connected to this Grounding Bus.
That 4/0 is certainly not a GEC. Is bonding jumper size, as per 250.64(E), an NEC requirement?
That 4/0 may be for lightning drain ?
Will be calling the Engineer next week of not showing the 4 AWG EGC not being connected to Isolated from equipment 'Grounding Bus' on the prints.
800.40 will be part of the subject as well as 250.106, 250.60 and 250.58.
Will need to see the existing Service Equipment to see how it is grounded. It is one floor down from the roof level.
gwz2
