MIL-DTL-26482 Series I circular connector | Vibration resistant | Salt spray resistant | High temperature resistant | Waterproof | Shockproof military circular connector，Aerospace Plug&Socket,MS3110E22-21SN

Product Overview

The MS3110E22-21SN is the wall-mounting square-flange receptacle from our MIL-DTL-26482 Series I range: shell size 22, contact layout 21 and socket contacts. It is the fixed half of the coupling — the part that bolts through a bulkhead or an enclosure wall while the plug stays with the cable assembly. It is a vibration resistant circular connector by construction rather than by claim, with the contact retention and coupling that keep a mated pair together on a moving platform.

Programs that order from a military circular connector supplier against a released drawing usually specify the receptacle first and match the plug afterwards, because the panel cutout and the cable assembly length are already fixed. That is the job this part does: an existing Series I drawing, an existing panel opening, and a connector that drops in for a new build or replaces a failed unit without a redesign. Aerospace integrators, naval and subsea equipment builders, combat-vehicle electronics shops and rugged panel builders buy this half for the same reason.

OEM programmes are the usual home for it. Whether you are fitting out a naval console or building to a waterproof circular connector OEM specification for a subsea buoy, one Series I interface keeps cable assembly drawings, spares and test fixtures common across every box on the programme.

Day to day the connector does very little that is visible. It sits in the panel, carries power and signal between the enclosure and the cable, and gets mated and unmated during test, transit and service. What matters is that an IP68 military circular connector still does that after years of vibration, salt air and thermal cycling.

Compliance and Certification

As a mil-dtl-26482 connector manufacturer we build this receptacle to MIL-DTL-26482 Series I, Revision G. Compliance is not a single stamp: it covers shell dimensions and the mounting interface, the insert arrangement and contact positions, the coupling and keying geometry, and the environmental and electrical test sequence the standard lays down. A part that meets the electrical ratings but misses the insert geometry is not a conforming part, and that is where substitutions tend to fail.

Manufacturing runs under an ISO 9001:2015 certified quality system. RoHS/REACH-compliant versions are available where a programme requires them; confirm the version you need when the order is placed, because the compliant build is a distinct configuration rather than a default.

The qualification side looks like this in practice: every connector is checked for sealing performance and high-vibration performance before it ships, rather than sampled from a batch and assumed. The temperature envelope is verified on the same basis, which is what separates a genuine high temperature circular connector from one that only quotes a number on a datasheet.

Electrical Performance

The contact system is the part of a connector that decides whether a signal stays clean over a platform life. Contacts here are precision-machined and plated gold over nickel: the nickel acts as a barrier layer so the gold does not migrate into the base metal, and the gold surface keeps contact resistance low and stable while resisting the fretting that vibration normally causes at a dry contact interface. In practice that covers control and signal circuits, sensor feeds and low-power actuator supplies — the bulk of what runs through a Series I insert on an avionics or vehicle wiring assembly. If a circuit draws more, split it across several contacts on the same insert or step to a shell that carries a heavier contact; this is not the part to push a heavy power feed through. This variant carries socket contacts, the S in the part number, so the mating plug supplies the pin side. Order the plug as a P variant at the same shell size and layout, and confirm the aerospace plug socket connector pair before the wiring assembly is cut. Termination method follows the wiring drawing rather than the connector itself, so if your shop works to a specific contact or tooling, confirm it with us when the order is placed and the right contacts ship with the shells. One practical note on signal density: keep a spare cavity or two on the drawing where the programme allows it. A Series I insert is not easy to expand later, and a couple of spare contacts cost far less than reworking a finished wiring assembly.

Mechanical Durability

• Shell and plating. The shell is aluminium alloy with cadmium plating to MIL-STD-171 — a specified finish rather than a cosmetic one, and one that can be checked and re-verified against a drawing at incoming inspection.
• Mating life. The coupling and contacts are rated for repeated coupling and uncoupling rather than a single installation, which suits a depot item that is mated at every test, transit and service event.
• Salt spray resistant connector. Plating and sealed interface work as a pair: the plating handles the external surfaces, and the seal keeps chloride out of the contact chamber. Neither alone would be enough for sustained marine exposure.
• Vibration resistant circular connector. Contact positions are fixed by the insert and the coupling ring locks the two halves together, so a cable assembly on a moving platform does not slowly work the interface loose. That slow loosening is the failure that shows up first on a non-keyed, non-locking connector.
• Finish options. The series is also available in black anodized (A), olive green cadmium (B), passivated stainless steel (S) and electroless nickel (L). Choose on corrosion regime first, then on whether the shell has to carry a bonding current — anodized surfaces insulate and need a masked bonding point.
• Coupling and grip. The coupling ring is knurled so it can be turned by hand in a glove, in poor light, or with limited access behind a rack. It is not a tool-tightened coupling and it should not be.
• Chemical exposure. The insert is a chemical-resistant thermoplastic, so hydraulic fluid, fuel and cleaning agents that reach the contact chamber do not soften it. Wipe rather than soak, and keep solvents off the grommet.

MIL-DTL-26482 Series I Interface

Series I is the bayonet-coupled branch of MIL-DTL-26482. The coupling is a quarter turn, the shell is keyed, and every shell size has defined insert arrangements, contact positions and a defined mounting interface. In a typical aerospace plug socket connector pair the receptacle stays bolted to the bulkhead and the plug travels with the cable assembly, which is exactly how this part is used. Because the interface is defined by the standard rather than by any one supplier, a Series I plug built to the same shell size and layout will mate it.

Keying is the detail that saves assemblies. The series carries several keying orientations — N, W, X, Y and Z — so two connectors of the same shell size can sit side by side on one panel without any chance of a cable assembly going into the wrong one. This part is built to the N (normal) orientation. If your drawing calls for a different key position, treat it as a variant to confirm before the order rather than something to force at installation.

The same standard also covers Series II, and both appear on aerospace and defense drawings. Keep the series consistent on a platform: a Series II plug is a different coupling from a Series I receptacle, so both halves have to come from the same series. Where a drawing already cites Series I, this is the part that satisfies it; where the drawing is still open, our Series II range covers the same standard with a different coupling.

Installation and Coupling

1. Prepare the panel. Cut and drill to the Series I drawing for shell size
2. The 3110 shell style is a square wall-mounting flange, so it presents a flat face and four mounting holes; dry-fit it before any cable is terminated.
3. Bolt the flange evenly. Tighten in a cross pattern to the drawing's torque. An over-tightened or warped flange distorts the insert, and a distorted insert makes the coupling stiff and the contacts misaligned.
4. Mate by the keyway, never by force. Line the key up, push straight, then turn the coupling ring to its stop.
5. Terminate the rear before the panel goes live. An IP68 military circular connector only holds its rating when the grommet and backshell are fully seated on the cable. A grommet pushed loosely over the cable jacket, or a backshell left off during commissioning, is an open path into the contact chamber.
6. Bond the shell to the panel. Shielding only works through a low-resistance path from the shell into the structure. Paint on the flange face, or a sealing gasket that insulates the shell, defeats the shielded construction the connector was built with.
7. Check before sign-off. Full coupling seat with no visible gap, continuity end to end, insulation resistance between contacts and shell, and a visual pass over the flange gasket and the rear grommet.
   • Sealed to a stated class. The connector is rated IP68, which is what lets it be mounted on a deck fitting or a buoy hull instead of inside a dry cabinet. It is a mated-pair rating: an uncoupled receptacle with its cap off is not protected.
   • Three seals, not one. The flange face seals against the panel, the coupling interface seals when the plug is fully seated, and the grommet seals the rear where the cable assembly enters. Service class E on this part is the grommet seal with a conductive shell, so the back of the connector is closed as well as the front.
   • What breaks the seal in service. A grommet cut back during cable rework and not reseated, a missing backshell, a flange bolted down over a damaged gasket, or a coupling turned short of its stop. Most leaks reported in the field trace back to installation rather than to the connector.
   • Thermal cycling. The seals have to stay flexible across the same temperature envelope as the contacts. Once a seal takes a permanent set it stops following the coupling face through expansion and contraction, so on a high temperature circular connector the sealing class and the temperature range are quoted together rather than separately.
   • For OEM programmes. Building to a waterproof circular connector OEM drawing usually means the sealing class has to be evidenced rather than stated. Ask for the sealing and vibration test record to travel with the shipment.
   • Storage and handling. Keep the protective cap on the receptacle until the cable assembly is ready, store parts in the original packaging, and do not let solvent or cutting fluid sit on the grommet. A contaminated seal is the most common cause of a first-mate leak.

Target Applications

• Aerospace avionics and flight control. Rack-mounted avionics and flight-control boxes use the receptacle on the box wall and the plug on the airframe wiring; the connector has to hold signal through vibration and pressure cycling, not just sit in a temperature chamber.
  • Ground combat vehicle electronics. Chassis wiring in tracked and wheeled vehicles take shock, dust and constant vibration, and the flanged mount keeps the wiring anchored to the hull instead of hanging on the contacts.
  • Naval shipboard equipment. As a salt spray resistant connector it belongs on deck and below-deck gear where spray, humidity and washdown are routine and repainting a corroded connector is not.
  • Undersea sensor arrays and communication buoys. Here the connector is the boundary between a dry electronics bay and the water, so the sealed interface and the rear grommet do the work a cable gland would do elsewhere.
  • Rugged industrial automation. Oil and gas, mining and heavy machinery panels use it where a commercial circular connector would need replacing every season.
  • Test and depot equipment. Bench wiring, depot test rigs and burn-in racks use the same part because it mates with what the platform already carries.

Technical Specifications

Supply and Lifecycle Value

• Lower lifecycle cost. The value of a conforming Series I part is measured in the service intervals it does not shorten: no field replacement, no depot rework, no unplanned downtime while a substitute is sourced.
• Simpler logistics. One interface across a platform means one family of spares, one set of test fixtures and one cable assembly drawing convention, instead of a different connector on every box.
• MIL-SPEC interoperability. The mating interface is defined by the standard, so the plug side is not locked to one source and a cable assembly built years ago still mates a receptacle built this year.
• Backward compatibility. Existing Series I panel cutouts, existing plugs and existing drawings keep working; this is a drop-in for a legacy part number rather than a new interface the panel has to be re-cut for.
• Consistent supply. Programmes that standardize on one source want the same build this quarter and next year. Buying from a military circular connector supplier that also builds the mating plug halves keeps both sides of a cable assembly on the same drawing and the same inspection basis.
• Obsolescence cover. Where a legacy Series I part number is being phased out elsewhere, the same shell size, layout and contact type can usually be supplied from this range; send the old number and we will confirm the match.

Ordering and Delivery

1. Send the part number exactly as it is printed. That one string is how a mil-dtl-26482 connector manufacturer reads shell style, service class, shell size, contact layout, contact type and finish back to you, so a dropped suffix gets caught before anything else.
2. We confirm the configuration against your drawing before the order is released, including the finish and the keying code, so what arrives matches the panel it is going into.
3. Tell us the destination and the date the build needs the parts. That lets us confirm the shipping route and the schedule in writing rather than in assumption.
4. Orders run on Flexible MOQs and Stable global delivery, so a single replacement and a full programme release go through the same steps.
5. Distributors restocking and OEMs building to a waterproof circular connector OEM schedule go through the same checks. Lead time and payment terms are confirmed at quotation, in writing, before the order is placed.

Technical Support & Model Matching

Selecting the right connector is rarely a one-line decision. Send us your drawing, part number or a sample, and our engineering team will confirm the matching shell size, contact arrangement, coupling and mounting style, cross-reference discontinued or alternate part numbers, and advise on sealing and flange options for your environment. We also help troubleshoot fit, mating and signal problems, and give installation and commissioning guidance so your line stays up. As a direct manufacturer, our answers come from the people who build the parts — from first enquiry through after-sales support.

FAQ