Extending service conductors when you replace a meter can

Yes, you can splice them: the NEC allows service-entrance and service-lateral conductors to be spliced with approved methods and materials, and the accepted layout is a rain-tight junction box on the riser just below the raised meter socket. The worked job below assumes the common setup: three 2/0 aluminum conductors on a 70 ft underground lateral, a 2 in PVC riser holding the old can at 36 in, and a socket that needs to go up. Swap in your own numbers where the site differs.

Can you splice service conductors that are too short?

Yes — the NEC allows service-entrance and service-lateral conductors to be spliced with approved methods and materials, so the accepted fix is a rain-tight splice box on the riser below the raised meter socket, sized at 8 times the raceway outside diameter.

The permission fits this job exactly: conductors that come up short when a socket is replaced or raised. Approved methods and materials means, in practice, a listed dual-rated splice block or an insulated compression connector inside an accessible box. The connector datasheet sits behind every torque value. A feeder splice follows the same logic, and what the NEC allows in a junction box splice on a feeder works one level down the same way.

The meter socket itself stays out of it. A socket is a termination point under the utility's seal, and its lugs take conductors, not splice hardware. The splice lives in its own box below the socket, where you can open it for service and the utility can add a seal of its own.

Bring the utility in first: they own the meter, they pull it, and they kill the lateral before anyone touches the conductors. The 2026 NEC cycle even clarified the splicing language for service conductors, a sign of how often this exact job comes up.

What parts do you need for the splice?

You need a rain-tight box with a gasketed cover, two listed 2 in PVC hubs, three dual-rated AL9CU insulated splice blocks for 2/0 aluminum, joint compound, a torque wrench, and about 5 ft of new 2/0 per conductor.

The kit in detail:

• Box, rain-tight, sized to the pull. Type 3R is the outdoor minimum, and the NEC's Table 110.28 lists which enclosure types suit rain, sleet and snow. For salt air or a corroding neighborhood, order stainless: we build 304 and 316L bodies to your width, height, depth and cutouts, from one piece. They are rated NEMA 4X / IP66 by the manufacturer; not UL listed. In US installations, NEC 110.28 says an IP code does not replace the enclosure type rating, so carry the NEMA type on the spec.
• A sealable cover. A hasp or padlockable latch accepts the utility's seal; if the seal needs a hole, it goes on the drawing as a designed cutout.
• Two listed hubs for the 2 in PVC, one into the bottom wall, one out of the top.
• Three dual-rated AL9CU insulated splice blocks in the 2/0 range, one per conductor.
• Wire brush and aluminum joint compound for the prep.
• A torque wrench reading in lb·in, set from the connector datasheet.
• About 5 ft of new 2/0 aluminum per conductor — the arithmetic sits in the steps.
• A listed bond lug for the box-to-grounded-conductor jumper.

The rating ladder above 3R, and what each type survives, is in the outdoor electrical enclosures guide.

How big does the splice box need to be?

Size the straight pull at 8 times the outside diameter of the largest raceway — 8 × 2.375 in = 19 in for the 2 in PVC riser — and an angle or U pull at 6 times, which gives 14.25 in.

The NEC's pull-box rules for circuit conductors 4 AWG and larger set that geometry. A straight pull needs box length of at least 8 times the outside diameter of the largest raceway; an angle or U pull needs 6 times. Both runs in this job are straight — riser into the bottom wall, conductors out the top wall to the socket — so 8 times decides.

The arithmetic: 2 in Schedule 40 PVC measures 2.375 in across its outside diameter. Straight pull: 8 × 2.375 in = 19.0 in [483 mm] of box in the run direction. Angle or U pull: 6 × 2.375 in = 14.25 in [362 mm].

A body 20 in tall × 16 in wide × 8 in deep clears the vertical pull with 1 in to spare; that is the box we would quote in 316L. Depth matters as much as height: 8 in leaves wrench swing around a 2 in hub nut, while 6 in makes every splice a knuckle-buster. Sizing from the conductors outward is the whole method in the enclosure sizing guide.

Where does the splice box go?

Hang the box just below the new socket on the riser, keep 3 ft of clear working depth in front of it for a 120 V-to-ground service, and leave the cover reachable so the utility can open and seal it.

NEC 110.26(A) fixes that working space: at least 3 ft (900 mm) deep for 0-150 V to ground in Condition 1, which a 120 V-to-ground service is. Add at least 30 in of width and room for a hinged cover to swing through 90 degrees. Keep the frontage clear for good — it exists for the utility's crew and the next electrician as much as for you.

Raising the riser has one ceiling: a meter-main that carries breakers falls under NEC 240.24(A), which caps the highest handle at 2.0 m (6 ft 7 in) above the floor or platform. The example raises the socket 24 in, from 36 in to 60 in, and everything stays reachable.

A PVC riser gives the box no raceway ground path, so bond the metal box to the grounded conductor the way the meter can itself is bonded. Use a listed lug and scrape the contact surfaces to bare metal; NEC 250.12 requires coatings off the bonding points. The fundamentals are in the grounding and bonding guide, and bonding a metal junction box with spliced feeder conductors shows the same joint on feeder work.

How do you make the splice step by step?

Utility disconnect comes first, because the lateral stays live at 120 V to ground even with every breaker off; after that, the nine steps below run from riser layout to torqued splices to a closed, gasketed cover.

1. Get the utility to kill the lateral. The conductors are fed from their transformer with no breaker of yours in between, so the crew pulls the meter and verifies absence of voltage before anything opens.
2. Set the new riser height and hang the box. Follow the utility's socket band; the example raises the socket from 36 in to 60 in and centers the box between old conductor end and new socket, so both pulls stay straight.
3. Put the holes on the drawing, not on the drill. Bottom and top entries sit on the riser centerline, sized for the 2 in hubs and at least 19 in apart. On a stainless body we cut them to your layout, and the cutout and gland guide walks hole placement and fitting choice.
4. Fit the two listed hubs with their gaskets at full thread engagement. Thin stainless walls leave little thread to bite, and when a gland is too short for junction box threads shows what a marginal bite looks like.
5. Pull the new 2/0 from box to socket. The arithmetic: 24 in of raise + 19 in through the box + 12 in of slack = 55 in, so 5 ft per conductor covers it with margin. Land the socket ends with real bending space; measuring wire bending space in a junction box gives the measurement habit.
6. Prep every aluminum surface within minutes. Wire-brush the conductors bright, then pack joint compound on at once. Oxide reforms on fresh aluminum fast, and it is what makes joints run hot.
7. Make the three splices with the AL9CU blocks. Stagger them along the box so the joints never sit side by side, and torque every screw to the connector's printed lb·in value. Aluminum terminations at outdoor enclosures covers the same metal in the same weather.
8. Bond the box to the grounded conductor with the listed lug, coatings scraped off the contact points, so a fault has a metal path instead of a person.
9. Decide the drain on purpose, then close and call. A wet-location box may take an approved drain of 1/8 to 1/4 in (3 to 6 mm) per NEC 314.15. A sealed Type 4X keeps its rating only with the drain engineered into the design, because the lowest-rated opening sets the assembly. Then: gasket seated, cover screws even, inspection, and the utility's reconnection.

What checks prove the splice is done right?

Pull-test each conductor, confirm the cover's gasket with a 5 minute hose test, and re-torque the six splice screws — two per block — after 24 h, when aluminum creep has done its loosening.

The rest of the pass:

• Pull test at every splice before the cover goes on. A block that lets go on the bench is a service call in a year.
• Water over the closed box for 5 minutes, then open and look for dry gasket faces. Dry is the pass.
• Heat under load. Scan the blocks with an IR gun after a month of service, or measure them during a later utility disconnect: any connector hotter than the conductor beside it is loose, and burned splice in an outdoor junction box: causes and fixes is the troubleshooting path when one is.
• Voltage drop, for the record. Standard conductor tables put 2/0 aluminum near 0.08 Ω per 1000 ft at 75 °C, so the added 10 ft round trip is 0.08 × 10 / 1000 = 0.0008 Ω. At a 100 A service that is 100 × 0.0008 = 0.08 V, about 0.03% of 240 V. The whole 70 ft lateral costs near 1.12 V, or 0.47%, before the splice.

What mistakes ruin the splice or the rating?

The expensive ones are splicing inside the sealed meter socket, ordering a 12 in box for a 19 in pull, and field-drilling a rated cover for a weep hole — each one costs an inspection failure or a dead rating.

• A splice under the socket cover. The socket takes terminations only; the three blocks live in the box below it.
• A 12 in body against a 19 in rule. Order the length from 8 × 2.375 in, and re-run 6 × OD the day a pull turns an angle.
• A field-drilled hole. Each opening you add becomes the assembly's rating, so weep holes, seal hasps and hub entries go on the drawing; the stainless factory-cutout checklist lists what to send.
• Torque by feel. Aluminum creeps loose under load; the datasheet's lb·in value plus the 24 h recheck is the whole defense.
• Working it hot. The lateral carries 240 V line to line with the main off, so the utility's disconnect is the only lockout that counts.

Catalog dimensions to compare

Compare these catalog dimensions with your component layout. Open each enclosure for its rating, material and usable space, then check those specifications against your application.

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