Cable entry for a push fit conduit enclosure hub

Short answer: cement an unthreaded strain relief cord connector straight into the plain hub with PVC solvent cement, and the entry seals to about IP54 [dust and splashing water]. When the box needs jet-proof sealing, cement a short conduit stub into the hub, cement a female adapter onto it, and screw in a threaded cord connector matched to the cable jacket. That route seals to IP66. Both fixes use the push-fit socket the box already has, and the 24 h solvent cure plus wet-location-rated cable decide whether the repair lasts.

Can you seal a cable into a conduit hub with no threads?

Yes: cement a nonmetallic strain relief cord connector straight into the plain socket with PVC solvent cement. The entry then seals to about IP54 [dust and splashing water]. For IP66, cement in a conduit stub and female adapter, then screw in a threaded gland.

A push-fit hub is a molded socket, not a tapped hole. It grips the conduit by friction and completes the joint with solvent cement. Schedule 40 PVC conduit gives you the dimensions to buy against: a 1/2 in trade-size socket takes a 0.840 in [21.3 mm] outside diameter, and a 3/4 in socket takes 1.050 in [26.7 mm]. Molded strain relief cord connectors are made for exactly this socket. They have a plain PVC shank sized to cement into an unthreaded hub.

Route A glues the cord connector in directly. Route B glues in a conduit stub and a female adapter, which puts a tapered female thread on the wall and takes a threaded gland or cord connector. Route B adds three parts and buys you a jet-proof seal instead of a splash seal.

Whichever you pick, the entry is the weak point and it sets what the whole box survives: one splash-only entry makes the assembly a splash-rated box. Keep the two systems straight too. IEC 60529 defines the IP digits, and in US installations NEC 110.28 has you specify the enclosure type number for the location, so an IP code alone does not carry a US spec. Our wall-mount boxes are rated NEMA 4X / IP66 by the manufacturer; not UL listed, and a field-built entry is your own assembly with your own seal level. The IP rating chart sorts out the digits, and the NEMA 4X vs IP66 pairing shows how the two systems sit side by side.

What parts do you need for each route?

Both routes share a short shopping list: PVC solvent cement and a connector matched to the cable — a 3/4 in trade-size cord connector typically clamps a 0.41–0.74 in [10.4–18.8 mm] jacket — and Route B adds a conduit stub, a female adapter and a threaded cord connector.

• PVC solvent cement, one-step type for PVC; primer when the cement maker calls for it.
• Unthreaded strain relief cord connector, trade size matched to the hub; a common 3/4 in model clamps a 0.41–0.74 in [10.4–18.8 mm] jacket.
• Schedule 40 PVC conduit for stubs, cut 1–2 in [25–50 mm] per entry (Route B).
• PVC female adapter, socket-to-female-taper, one per entry (Route B).
• Threaded cord connector or cable gland with a male taper thread and a clamp range covering the jacket OD (Route B).
• PTFE thread tape, 2–3 wraps per threaded joint.
• Wet-location cable: UF, or THWN conductors inside conduit, for anything outdoors.

How do you match the connector to the cable OD?

Measure the jacket with calipers and buy the connector whose printed clamp range covers it with margin: a 0.55 in [14.0 mm] jacket sits inside a 0.41–0.74 in [10.4–18.8 mm] connector with 0.14 in [3.6 mm] and 0.19 in [4.8 mm] to spare.

Run the numbers before you order anything:

• Measure. Calipers on the jacket, mid-span and clear of print: 0.55 in. Converted, 0.55 in × 25.4 = 14.0 mm.
• Candidate. A 3/4 in trade-size cord connector with a printed clamp range of 0.41–0.74 in [10.4–18.8 mm].
• Margins. 0.55 − 0.41 = 0.14 in [3.6 mm] above the low end. 0.74 − 0.55 = 0.19 in [4.8 mm] below the high end.
• Decision. Both margins clear a 0.05 in [1.3 mm] margin floor, so the connector grips mid-range and Route A stands.

A jacket within 0.05 in [1.3 mm] of either printed limit sends you to Route B, with a gland whose clamp range centers on the measured OD. Gland sizes run by jacket diameter, which is why the PG7 cable gland alternatives article says to check the clamp range against the cable before you order, not after.

How do you cement a strain relief into a push fit hub?

The hub joint is a solvent weld: clean, dry PVC on both surfaces, cement on each, full insertion with a quarter turn, then 24 h of cure at room temperature before the entry meets water.

1. Switch the circuit off, lock the source, and verify absence of voltage in the box before you touch anything.
2. Dry-fit the connector shank into the hub and mark the insertion depth on the shank.
3. Wipe the hub socket and the shank with a clean dry cloth; apply primer first where the cement maker calls for it.
4. Brush an even coat of cement over both surfaces, socket and shank.
5. Push the connector to your mark with a quarter turn, hold it 30 s while the weld grabs, and wipe off the excess bead.
6. Give the joint 24 h at room temperature before anything wet touches it; near freezing, plan on about 48 h and use a low-temperature cement.
7. Feed the cable through the clamp dome into the body, seat the seal square on the jacket, and tighten the dome screws evenly.
8. Dress a drip loop below the entry and support the cable within a few inches, so the cured joint never carries the cable's weight — the cable strain relief for sealed entries article covers the support details.

Most cemented joints that fail were dirty, wet or moving while they cured; the PVC solvent cement joint failure analysis page walks through the failure modes one by one.

How do you add threads for a rated gland?

Cement a 1–2 in [25–50 mm] stub of Schedule 40 PVC conduit into the hub, cement a female adapter onto the stub, and screw in a threaded cord connector hand-tight plus 1–2 turns over 2–3 wraps of PTFE tape.

1. Cut a stub of Schedule 40 conduit 1–2 in [25–50 mm] long and deburr both ends, inside and out.
2. Cement the stub into the hub as in the section above, and cement the female adapter onto the stub in the same session; keep the tapered threads clean and cement-free.
3. Let the whole chain cure 24 h.
4. Wrap the gland's male taper thread with 2–3 wraps of PTFE tape and leave the first thread bare, so tape shreds stay out of the box.
5. Screw the gland in hand-tight plus 1–2 turns; past that you crack the PVC female threads, and the taper needs no wrench to seal.
6. Clamp the gland onto the jacket. The elastomer seal inside the clamp is what stops a jet, so the OD match from the last section is the whole game.

IP66 is a jets rating: IEC 60529 runs the second-digit-6 test with a 12.5 mm nozzle at 100 L/min from 2.5 to 3 m [8–10 ft] for at least 3 min. A garden hose from the same distance is a fair field imitation. If the gland you bought carries a G (parallel) thread instead of a taper, the G thread vs NPT cable gland article explains which adapter actually seals. And point the entry down or sideways; where a wall forces the entry off the top, the conduit hub vs sealing locknut article compares the sealing options.

How do you check the finished entry?

Prove the entry with three checks: a 10 s hand tug on the cable, a bucket pour over the cured hub, and an inside inspection for droplets after the first real rain.

• Tug. Pull the cable hard by hand for 10 s. The clamp must hold with no sliding at the seal.
• Pour. After the 24 h cure, pour a bucket of water over the hub and look inside after 5 min. A weep at the joint means the weld never fused; cut the cable out and start again.
• Hose. On a Route B entry, run a garden hose over the hub from 8 to 10 ft [2.5–3 m] for 2–3 min and open the box straight away.
• First rain. Open the box after the next rain and look for droplets on the lid or water pooled at the bottom. A few drops at an entry mean re-tighten the dome or re-seat the seal.

Which mistakes cost you the seal?

The seal usually dies one of four ways: the joint was wet or dusty at cementing, the clamp grips the inner conductors instead of the jacket, the entry faces upward, or the cable itself is dry-location rated.

• Wet or dusty joint. Water or dust in the socket stops the cement from dissolving the surfaces; the joint looks done and weeps at the first rain.
• Clamp on the wrong layer. Set the seal on the outer jacket. A clamp through the conductors' insulation leaks along the cable and works the copper.
• Upward entry. A sky-facing hub collects water all day and holds it against the seal; point entries down or sideways.
• Dry-location cable. The best IP66 entry cannot save interior-rated cable — run UF or THWN-in-conduit outdoors.
• Silicone stuffing. A bead over an unsealed hub is a splash seal that releases from PVC with temperature cycling; build the clamped seal instead.
• Wrench on PVC threads. Hand-tight plus 1–2 turns seals a taper; more cracks the female adapter, and the crack shows up as a drip down the wall.

The cable gland hazards article lists the rest of what goes wrong at entries, from undersized clamps to cut jackets.

When is a new box the better fix?

Fix the hubs you have when the bodies are sound — 30 boxes cost an afternoon and one can of cement — and swap the box when a body is cracked or unlisted or you want factory-cut threaded entries in stainless.

• Convert the boxes you have when the bodies are sound and the cable is already outdoor-rated: 30 boxes take an afternoon of fitting and one overnight cure.
• Swap a box when the body is cracked, when it was never meant for outdoors, or when you want factory-threaded entries. Our wall-mount stainless enclosures start at 8 x 6 x 4 in (H x W x D); an 8 x 6 x 4 in 304 box or the same 8 x 6 x 4 in size in 316L takes two 3/4 in entries. Set the gland positions on the drawing through the custom stainless cutout page, and it is delivered in 10 business days, counted from your approval of the drawing.
• Pick the grade by exposure. 304 for dry landscape walls; 316L wherever salted irrigation, coastal air or pool decks reach the box. Molybdenum in 316L raises pitting and crevice resistance, and chloride deposits pit 304 even at room temperature.
• Put drains in the spec, not the drill. NEC 314.15 permits approved drainage openings of 3 mm (1/8 in) to 6 mm (1/4 in) in boxes listed for damp or wet locations; keep any opening inside that band and only on a box listed for the location.

Decision, case by case:

Enclosures in this article

Questions