MIL-DTL-26482 Series I circular connector | Vibration resistant | Salt spray resistant | High temperature resistant | Waterproof | Shockproof military circular connector，Aerospace Plug&Socket, MS3116F12-4S

Product Overview

This plug is the cable-end half of a MIL-DTL-26482 Series I coupling: a straight plug in shell size 12, built on the 12-4 contact arrangement with socket contacts. The letter F in the part number is the service class — a grommet seal in a conductive shell with a cable clamp backshell — so the plug arrives ready to take a jacketed cable, grip it at the clamp, and mate with a fixed receptacle on the equipment side. The reason to choose this variant over another plug in the range is temperature headroom. It is specified across a wide operating envelope, so a cable routed near an engine, along an exhaust path or inside a sun-loaded equipment bay does not have to switch to a different connector family. Buyers hunting a high temperature circular connector for exactly that kind of routing usually arrive at this service class and this shell size. In use it is an aerospace plug socket connector of the ordinary working kind: it carries power and signal between a cable and a panel, it is mated and unmated every time the equipment is serviced, and it is expected to survive that treatment for years. In the hand it is a compact metal barrel with a knurled coupling ring, a blue insulator insert holding the contacts, and a clamp backshell at the rear. Most of these plugs are bought to put a cable back in service rather than to design a new connection. When a plug end is damaged — a bent shell, a cracked insert, a contact that no longer holds — the assembly is cut back, a new plug terminated on the same cable, and the cable assembly returns to the bench, the vehicle or the aircraft with the panel receptacle untouched and no drawing change.

Key Features and Engineering Advantages

A MIL-DTL-26482 Series I connector is judged on four things once it is in the field: whether the seal holds, whether the contacts stay clean and stable, whether the shell survives the environment, and whether a technician can fit it without damaging it. The four sections below take those in turn. Advanced Environmental Sealing

Sealing starts at the rear of the insert and ends at the mated interface. A grommet closes around each contact as it enters the shell, the plug-to-receptacle joint is sealed once the coupling ring is fully seated, and the clamp backshell takes the cable's weight so the seal never has to carry it. Temperature is the other half of the environmental picture. Seals are usually what fail first in a swing like that, which is why the grommet and the interface seal matter more here than the headline figure does. The nickel underplate is the barrier layer; the gold gives a surface that does not oxidise between services, so contact resistance stays low and stable instead of creeping up over a service life. On sensor and low-level signal circuits the stable contact resistance matters more than the headline rating — it is what makes a reading repeatable from one service to the next. Enhanced Mechanical Durability

The shell is aluminium alloy with cadmium plating, and the insert is a chemical-resistant thermoplastic that holds the contacts in alignment through mating cycles and temperature swings. The connector is rated for 500 mating cycles minimum. A vibration resistant circular connector earns that description at the coupling rather than in the data sheet: the keys engage, the ring seats fully, and the two halves stay seated under sustained vibration and shock instead of creeping apart. Cadmium plating is what keeps the coupling turning in salt-laden air, and a seized coupling ring is the usual reason a plug is scrapped long before its contacts are worn. Ruggedized Installation Features

Everything a technician needs to fit the plug is part of the plug. The keyway prevents a mis-mate, the polarised contact layout prevents a wrong arrangement being forced home, and the clamp backshell provides the strain relief so the termination is not loaded by the cable hanging off it. The conductive shell also screens the contact pair, which is why the mated assembly carries an EMI/RFI shielding specification — a detail that matters when a cable run shares a bay with switching equipment. A waterproof military circular connector is only waterproof if it is assembled that way, so the seal belongs on the inspection list at termination and at every mating, not just in the specification.

Compliance and Certification

1. MIL-DTL-26482 Series I, Revision G. Built to the full series specification, which is what separates a genuine high temperature circular connector from a shell that happens to fit the same hole.
2. ISO 9001:2015. Manufactured at our waterproof circular connector factory under a certified quality management system.
3. MIL-STD-171. Cadmium plating on the aluminium alloy shell is applied to this specification.
4. MIL-STD-461. EMI/RFI shielding effectiveness of the mated assembly is specified against this standard.
5. Vibration and shock. The keyed, polarised coupling is what makes a vibration resistant circular connector hold its position; the coupling and the contact retention are both checked, not assumed.
6. Production testing. Units are tested for sealing performance and high-vibration performance before shipment by the MIL-DTL-26482 connector manufacturer, not only at the design stage.
7. RoHS and REACH. Compliant versions are available for markets that require them; state the requirement with the enquiry so the correct version is quoted.

Part Number and Series Guide

- Shell size and insert arrangement define the pair. This plug is shell size 12 on the 12-4 arrangement, so the mating half must present the same 12-4 insert. A receptacle of the right shell size but a different arrangement will not seat, and no amount of ring torque will compensate.

• The contacts sit the other way round. The plug carries sockets, so the receptacle it mates with carries pins. When you order the fixed half, specify 12-4 with pin contacts.
• Any mount style of the same insert will mate. The wall-mount square (3110), box-mount square (3112), jam-nut (3114) and thru-bulkhead (3117) receptacles all present the same Series I interface. The style letter changes how the receptacle is fixed to the panel, not whether this plug couples to it.
• Keying orientation has to match. Series I shells are keyed to one of several orientations, marked N, W, X, Y or Z in the part number. If the receptacle is keyed differently, the plug will not enter — that is the keyway doing its job, not a defective part. Read the orientation from the receptacle's own part number or its shell marking before ordering.
• Service class is a backshell question, not a mating question. The letter after the shell style — F on this plug — describes the grommet, shell and cable clamp on that half. It changes cable entry and sealing, not the interface, so a receptacle in a different service class still mates.
• Series I and Series II are separate coupling systems. Both sit under MIL-DTL-26482, but a Series II receptacle is not automatically the mating half for a Series I plug. Confirm the series first, then the shell size, insert and contact type.
• How to confirm before the order goes in. Work from the receptacle's part number or from the marking on the old part: series, shell style, shell size, insert arrangement, contact type and keying orientation. A photo of the receptacle face with the old plug beside it is usually the fastest check our team can run, and it is the check that keeps a wrong-half shipment off the dock.

Target Applications

• Avionics and flight-control harnesses. Cable assemblies that run from an equipment bay to a panel-mounted receptacle, mated at every service and absorbing the temperature swing between ground and altitude. This is the build where buyers judge a MIL-DTL-26482 connector manufacturer on whether the exact insert arrangement is available, not only on the headline figure.
  • Field repair and re-termination. A damaged plug end replaced on an assembly that is otherwise sound, with the receptacle left in place and the cable reused after being cut back. The seal on a waterproof military circular connector is made at the grommet, so the repair is only as good as the termination behind it.
  • Ground vehicle and mobile platform electronics. Wiring that sees continuous shock and vibration from the chassis, plus dust and washdown, taken through a sealed circular interface because a round shell couples faster in the field than a rectangular one.
  • Test and ground-support equipment. Racks and rigs where the same aerospace plug socket connector is mated and unmated many times a week; the contact plating is what makes that routine survivable.
  • Rugged industrial automation. Oil and gas, mining and heavy machinery control cabinets that need a sealed, vibration-tolerant interface without a defence programme wrapped around it.

Technical Specifications

Ordering and Delivery

1. Start from the part number on the drawing. Send the part number, or the shell size, insert arrangement and contact type you need, and we will match it against the range. The full range is held in stock but not every variant is listed, so a configuration you cannot find listed is still worth asking about.
2. Flexible MOQs. We work to flexible MOQs, so a repair order for a single plug and a scheduled release for a production build both fit the same process. Confirm the current minimum for your exact configuration with your sales contact.
3. Stable global delivery. We maintain stable global delivery on this range so a build schedule does not slip while it waits on a connector; the shipping method is agreed when the order is confirmed.
4. Lead time. Production lead time depends on the configuration and the current schedule. Confirm it with your sales contact when you place the order rather than planning around a published figure.
5. Direct supply. Orders are handled by the waterproof circular connector factory that builds the parts, which is why a question about a seal, a plating or a contact goes to the people who make it.
6. Packing, paperwork and trade terms. Export packing, the inspection documents that travel with the shipment, and the trade term — FOB, CIF, CNF or another method — are agreed at quotation together with the payment schedule. Tell us at enquiry if your incoming inspection needs particular paperwork.
7. Support before and after the order. Working as a military circular connector supplier for cable assembly shops and depots means the same team handles the drawing question, the substitution question and the after-sales question.
8. - Direct from the manufacturer. This plug is shipped by the MIL-DTL-26482 connector manufacturer, so the seal, the plating and the contact set are controlled by the same plant that answers the technical question.
   • A standard part rather than a special. Being a catalogued MIL-DTL-26482 Series I connector means it fits assemblies specified around the series, without a drawing change or a fresh qualification cycle.
   • Longer service intervals. The failures that usually end a connector's life — a seized coupling, a corroded shell, a contaminated contact — are the ones this build addresses, so inspection can be planned instead of reactive.
   • Simplified logistics. One shell size and one insert arrangement cover the cable side of several assemblies, which keeps the spares list short and kitting simple.
   • Backward-compatible fit. The interface follows the standard, so replacing an existing plug changes nothing on the receptacle, the panel cut-out or the cable drawing.

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 waterproof circular connector factory, our answers come from the people who build the parts — from first enquiry through after-sales support.

FAQ