How to Set a Light Pole Base

1. Start from the pole submittal, not the site plan

The site plan puts the pole at a coordinate; the pole submittal defines everything else — bolt circle diameter, bolt size and projection, base plate dimensions, handhole size and orientation, and the foundation detail from the project engineer. Order the anchor bolt kits with the poles and build or obtain a rigid setting template for each bolt pattern. Guessing a bolt circle from a catalog cut sheet is how four 1 in. bolts end up half an inch off a pole that took eight weeks to arrive.

Check the electrical against the structural: foundation depth and diameter come from the engineer based on soil and the pole's EPA (effective projected area) wind loading — in monsoon country that's not a place to freelance. Confirm which way the handhole faces on each pole per the plan (typically away from traffic view, toward the access side) because handhole orientation fixes template orientation.

2. Set the conduit inside the bolt circle — and prove it before the pour

The conduit stubs must rise inside the pole's base opening — comfortably inside the bolt circle, clear of the anchor bolt cage, at the projection the detail calls for. Sweep up with long-radius elbows, transitioning to Schedule 80 or rigid steel through the concrete per 300.5(D)(4) practice, and strap the risers rigidly to the rebar cage or bracing so the pour can't shift them. A stub cast against the bolt circle leaves no room for the conductors to enter the pole.

Bring in as many conduits as the circuiting requires plus a spare where budget allows — poles are junction points for the run continuing to the next pole, so most bases get two conduits (in and out) and the end-of-run gets one. Leave the stubs long; cutting to final height at pole-set is a saw cut, while extending a short stub means chipping concrete.

Cap and tape everything, then verify geometry one last time with the template sitting on the actual bolts and the stubs visible through it before anyone pours. Photograph each base with the template on — it's the cheapest insurance in the whole job.

3. Place the anchor bolts with the template and pour

Hang the anchor bolt cage from the rigid template at the correct projection — threads up, typically with the bolts tied to the rebar cage below. Level the template in both axes and secure it against movement; a template that drifts during the pour bakes a tilt into the pole that leveling nuts can only partially rescue. Double-check bolt projection: too short and the nut doesn't fully engage, too long and the pole base sits on threads.

Pour and consolidate per the structural detail, then finish the top surface flat and slightly crowned so water sheds. Protect the bolt threads from concrete splash — taped or sleeved — because wire-brushing concrete out of one-inch threads is nobody's favorite afternoon. Let the foundation cure to the engineer's strength requirement before loading it with a pole and a crane pick.

While the concrete is workable, orient and set any grout dam or chamfer, and re-verify the handhole side against the plan one last time.

4. Ground and bond per 410.30(B) — the handhole rules

NEC 410.30(B) permits a metal or nonmetallic pole to enclose the supply conductors provided it has a handhole — at least 2 in. × 4 in. — with a rain-tight cover giving access to the terminations inside. The exceptions: poles 8 ft or less where the wiring is spliceless and accessible by removing the luminaire, and poles 20 ft or less on a hinged base. If the pole uses a hinged base, the hinged base and pole must be bonded together.

The equipment grounding terminal must be accessible from the handhole (or within the hinged base). Land the circuit EGC — sized from Table 250.122 for the branch OCPD — on that lug, and bond the metal pole. The EGC run with the circuit conductors is what clears a fault; a ground rod at the pole is supplemental at best. Where the design includes a rod (common for lightning exposure on tall poles), bond it to the pole ground lug, but never treat it as a substitute for the EGC — earth is not an equipment grounding path.

Where the spec puts in-line fuses at the handhole, fuse the ungrounded conductors only, with the fuseholder rated for the location. Neat, tucked, and dry: everything in that handhole gets serviced at arm's length through a 2×4 opening by the next person.

5. Mind the voltage rules: 277V is easy, 480V has a height gate

Most commercial site lighting runs 277V, which 210.6(C) permits for listed LED and discharge luminaires without drama. Running area lighting at 480V line-to-line buys you half the current and smaller conductors on long runs — but 210.6(D) gates it: luminaires on circuits over 277V-to-ground territory land under the not-less-than-22-ft pole height rule for area lighting. If the design shows 480V circuits to 20 ft poles, raise the question before the gear is bought, not after.

Voltage drop, not ampacity, sizes most parking lot circuits: a 277V run to the back of a big lot can be over 500 ft. Do the math per pole with the actual load and distance — upsizing from #10 to #8 or #6 on the long legs is routine. Run the numbers with our voltage drop calculator before pricing conductor.

Label circuits at every handhole and at the contactor. Site lighting gets serviced at 2 a.m. by whoever answers the call; the label is your gift to them.

6. Set the pole: leveling nuts, torque, and closeout

Set poles with leveling nuts and washers below the base plate, plumb the pole in two axes with a level on two faces, then run down the top nuts. Torque anchor nuts to the pole manufacturer's values — not ‘tight’ — and re-check after the first storm season on tall poles if the manufacturer recommends it. Where the detail calls for grout under the base plate, follow it exactly; some pole designs require the plate left open for drainage and inspection instead.

Feed the conductors, terminate at the handhole with the in-line fuses where spec'd, land the EGC on the ground lug, and megger each circuit before energizing — a staple through insulation at pole 7 is easier to find now than after the contactor closes at dusk. Verify the photocell and contactor sequence, then walk the lot at night: every pole burning, no misaims into neighboring property.

Update the as-builts with actual pole locations, circuit assignments, and conductor sizes, and turn over the pole submittals and torque records with the O&M package.

Do all light poles need a handhole?

Poles used as the raceway for supply conductors need the 2×4 in. handhole per 410.30(B), with two exceptions: 8 ft or shorter poles with spliceless wiring accessible at the luminaire, and 20 ft or shorter poles on a hinged base. The grounding terminal must be accessible through whichever access the pole uses.

Is a ground rod at each pole required?

The NEC doesn't require one — the equipment grounding conductor run with the circuit is the required fault path. Rods at poles are a design choice, common on tall poles for lightning exposure. If present, bond them; never use one in place of the EGC.

Why do specs put fuses in the pole handhole?

In-line fuses isolate a single pole's fault — a ballast/driver failure or a wire chafe in the pole — so one pole goes dark instead of tripping the whole contactor circuit. They also give a service point at the pole. Fuse ungrounded conductors only.

What's the advantage of 480V site lighting?

Half the current of 277V for the same load — smaller conductors and less voltage drop on big lots. The cost: 210.6(D) height conditions (22 ft minimum poles for area lighting), higher-rated gear, and a smaller pool of familiar service techs. Most lots pencil out fine at 277V with upsized conductors.

Direct-embedded or anchor-bolt base — who decides?

The engineer, from soil conditions and pole loading. Direct embedment suits smaller poles and decorative work; anchor-bolt foundations dominate commercial lots because they're serviceable — a car-struck pole unbolts and replaces without touching the foundation.

How plumb is plumb enough?

The pole manufacturer's tolerance governs, but the practical standard is 'no visible lean from any angle' — leveling nuts give you a degree or two of correction at most. A visibly leaning pole is a foundation problem, and re-torquing nuts won't fix it.