How to ground a bollard?

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Cadweld to post and run a bare #2/0 AWG and connect to the ground ring/ground grid. Are there transmission or distribution lines in the area? That would have an affect. Seen it many times on fences. Most likely they are concerned with touch potential issues. I would think static charge would be eliminated by the burial in the ground.

The best part of this plan is that it is fun to cadweld and with 2/0 copper the installation will tough enough to last longer than we will.
 
About a bazillion years ago I was at a refinery in Canada.

They had small fiberglass huts outside of some buildings where workers could go and smoke. I thought they were portapotties at first.

In the building I was at they had a picnic table inside the building with a yellow box painted on the floor around it. That was the designated smoking area for that building. The rest of the building was classified as div 2. Why the area inside the yellow box came to be declared unclassified has always been a bit of a mystery to me.

The point is that sometimes we do things for no real good reason.
 
Either way the question remains, the conductor size would be based off of what?
NEC 250.66(B) Connections to Concrete-Encased Electrodes.
Where the grounding electrode conductor is connected to a
concrete-encased electrode as permitted in 250.52(A)(3),
that portion of the conductor that is the sole connection to
the grounding electrode shall not be required to be larger
than 4 AWG copper wire.

If he drove a ground rod and ran the GEC from the bollard to the rod, then he would only have to use 6 AWG CU wire per 250.66(A). But I figured there would already be a Ufer available in the concrete work, so easier to run 6AWG than to install a ground rod.
 
~ ( & ) ~

"greenspark1 asked:

But it's what the client says the utility requires it in their neck of the woods
(Canada)."


"NEC 250.66(B) Connections to Concrete-Encased Electrodes.
Where the grounding electrode conductor is connected to a
concrete-encased electrode as permitted in 250.52(A)(3),
that portion of the conductor that is the sole connection to
the grounding electrode shall not be required to be larger
than 4 AWG copper wire.

If he drove a ground rod and ran the GEC from the bollard to the rod,
then he would only have to use 6 AWG CU wire per 250.66(A)..........But
I figured there would already be a Ufer available in the concrete work,
so easier to run 6AWG than to install a ground rod."
Unless Canada; or that specific AHJ, has adopted the NEC, ...I'm pretty
sure that no NEC Article will be applicable. :cool:



~ ( & ) ~
 
I don't know if this helps but I installed 2 4in bollards w/ an OZ Gedney 4 device fitting on the top on a farm center Im working at volunteering my time. Anywho I torched a channel in the side below grade to run my 1 1/4 pvc up through centered it w/in the bollard and filled the bollard and immediate area w/ concrete. We needed something that could be set in the field for events farm festivals etc., and that would take a beating if accidently struck or backed into. Anyway I was not happy with the ground screw that came on the fitting for bonding the bollard so I opted to drill and tap the top of the bollard and placed a bonding lug at the top, on the inside and connect to the ground. So if your ground has to be accessible maybe an option is this and a threaded cap on the top then to hide the bond. just an idea.
 
How about you use a 4AWG wire to connect the bollard to itself :), since its mounting serves as a concrete encased electrode, just not one large enough to be used for the sole GE of a building.

I'm picturing a lug or clamp at the top and one at the bottom of this pipe with a copper conductor (not yet determined the size but probably 4 AWG because of a concrete encased elecrode) between them:huh:

Cadweld to post and run a bare #2/0 AWG and connect to the ground ring/ground grid. Are there transmission or distribution lines in the area? That would have an affect. Seen it many times on fences. Most likely they are concerned with touch potential issues. I would think static charge would be eliminated by the burial in the ground.
I thought this was a hazardous location area, now lets make it even more hazardous by running HV transmission lines directly over the place:cool:
 
I have a client who is asking us to ground the metal vehicle bollards we're putting in. OK. I've never seen a listed device to attach to a bollard. Do you use a large pipe clamp, or just tap a bolt in and connect it to the grounding system? I've seen a spec calling for it above grade but this seems like it'll look really poor. Any good ideas on this one?

Sounds like he's looking for electrostatic discharge mitigation via bonding of everything conductive because of fuel pump fires caused by static electricity.

Another option he has is don't let women pump gas - it's always women who blow up those gas pumps! In Fire Marshal school we had to watch videos of pumps blowing up and it was always a woman who had always started pumping fuel, then got back in the car, then got back out of the car. They've looked into what they were wearing, what kind of car interior they have, etc. and as of that time (10+ years ago) had not concluded anything.

What good is bonding the bollards going to do? Other than make him feel safer maybe not much. The source of ignition is between the user and the pump handle or vehicle metal.
 
If the concern is bonding of the bollards for static control, NFPA 77 addresses this. Here is an excerpt on bonding and grounding that may help.

7.4.1 Bonding and Grounding. Bonding is used to minimize
the potential difference between conductive objects, even where
the resulting system is not grounded. Grounding (i.e., earthing),
on the other hand, equalizes the potential difference between
the objects and the earth. Examples of bonding and grounding
are illustrated in Figure 7.4.1.

7.4.1.1 A conductive object can be grounded by a direct conductive
path to earth or by bonding it to another conductive
object that is already connected to the ground. Some objects are
inherently bonded or inherently grounded because of their contact
with the ground. Examples of inherently grounded objects
are underground metal piping and large metal storage tanks resting
on the ground.

7.4.1.2 The total resistance between a grounded object and
the soil is the sum of the individual resistances of the ground
wire, its connectors, other conductive materials along the intended
grounding path, and the resistance of the ground electrode
(i.e., ground rod) to the soil. Most of the resistance in a
ground connection exists between the ground electrode and
the soil. This ground resistance is quite variable because it
depends on the area of contact, the resistivity of the soil, and
the amount of moisture present in the soil.

7.4.1.3 To prevent the accumulation of static electricity in conductive
equipment, the total resistance of the ground path to
earth should be sufficient to dissipate charges that are otherwise
likely to be present. Aresistance of 1 megohm (10E6 ohms) or less
generally is considered adequate.

7.4.1.3.1 Where the bonding/grounding system is all metal,
resistance in continuous ground paths typically is less than
10 ohms. Such systems include those having multiple components.
Greater resistance usually indicates that the metal path is
not continuous, usually because of loose connections or corrosion.
A grounding system that is acceptable for power circuits or
for lightning protection is more than adequate for a static electricity
grounding system.

7.4.1.3.2 Annex G contains diagrams of various grounding
devices, connections, and equipment.

7.4.1.4 Where wire conductors are used, the minimum size of
the bonding or grounding wire is dictated by mechanical
strength, not by its current-carrying capacity. Stranded or
braided wires should be used for bonding wires that will be
connected and disconnected frequently. (See Annex G for additional
information.)

7.4.1.5 Grounding conductors can be insulated (e.g., a jacketed
or plastic-coated cable) or uninsulated (i.e., bare conductors).
Uninsulated conductors should be used because defects are
easier to detect.

7.4.1.6 Permanent bonding or grounding connections can
be made by brazing or welding. Temporary connections can
be made using bolts, pressure-type ground clamps, or other
special clamps. Pressure-type clamps should have sufficient
pressure to penetrate any protective coating, rust, or spilled
material to ensure contact with the base metal.
 
Either way the question remains, the conductor size would be based off of what?
Whatever the people paying the bill want run.

The best part of this plan is that it is fun to cadweld
yeppers.
and with 2/0 copper the installation will tough enough to last longer than we will.
If anybody asks, that is what I would recommend.
 
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