Y3B series circular electrical connector,Y3B-2004TK5 | Y3B-2004ZJ

Product Overview

Y3B series circular electrical connector is a high-precision aviation connector built on a push-pull locking body. Push the plug home and it locks; pull the outer shell back and it releases. There is no thread to cross and no coupling ring to torque, which makes the series quick to handle during assembly and easy to service in a crowded panel.

Gold-plated contacts sit inside the shell and carry signal and power through the same connection, holding contact resistance low and giving the interface a long working life. A stable, low-resistance contact is what keeps a control signal clean and a supply voltage steady over years of mating cycles.

Two references make up this product: Y3B-2004TK5 and Y3B-2004ZJ, the two halves of a single connection. Order the reference that matches the part you are replacing or the drawing you are building to, and send both numbers if only one half is worn so the pair can be confirmed before packing.

The series sits alongside the Y3, Y3A and other Y-prefix families in our range, so a wiring assembly already built around Y-pattern circular shells can add, replace or extend a connection here without reworking the rest of the assembly. You will find it in aerospace wiring, military equipment, industrial automation cabinets and electronic communication gear — anywhere a compact round shell has to hold a stable signal and power connection in conditions that are less than kind.

Push-Pull Locking & Mating

• Lock on insertion. Push the plug until the shell seats; the locking element engages over the mating shoulder and holds the pair together without any rotation, so the connection is made in one straight movement.
• Release on the shell, not the cable. Pulling the outer shell rearward frees the lock; pulling the cable instead loads the contacts and the wire termination, which is the most common way a good connector gets damaged.
• Held under vibration. The lock keeps the pair seated while the equipment it is mounted on shakes, which is why this style is chosen so often for military circular connector work in vehicles, airframes and portable sets.
• Predictable on every mating. There is no torque value to meet and no thread to wear, so the fiftieth mating feels like the first — useful when a technician is working by feel inside a rack or under a panel.
• Fast in service. Release takes one pull, so fault-finding does not turn into a fight with a coupling ring, and a swap in the field takes seconds rather than minutes.
• Clear feedback. The seat is felt as well as seen, so a half-mated pair is obvious before the equipment is energised.
• Mate on the keyway. Line the keys up and push; if the halves will not seat with light pressure, the keying is wrong, and force will damage the contacts rather than persuade them.

Gold Contacts & Electrical Behaviour

Gold plating is the heart of the electrical side of this connector, and it is the first thing buyers ask about when they approach us as a military grade connector supplier. Gold does not oxidise in normal service, so the contact surface stays clean and the resistance across the mated pair stays low from the first insertion to the last. In practice that shows up as a supply voltage that does not sag as the interface ages, and a signal line that does not develop the intermittent faults that are so hard to trace later.

Low contact resistance also means less heat at the contact under load, which protects both the plating and the insulator around it over a long service life. For anyone building an aerospace circular connector cable assembly, that pairing — stable resistance plus a contact that does not corrode — is what turns a connector into a part you can stop thinking about.

The same shell carries power and signal together. Instead of a separate connector for a low-level signal and another for a supply, one Y3B interface handles both, which simplifies cable routing, cuts the number of panel penetrations and takes parts off the bill of materials.

Electrical behaviour is also a mechanical story. A contact stays stable only if the mating halves stay fully seated, which is where the push-pull lock and the vibration resistance of the body do their work. The two are designed as a pair: a body that holds position and a contact system that stays clean.

Treat the gold as a working surface rather than a finish. Keep contacts covered until the moment of mating and avoid touching the faces, and the low-resistance performance you specified is the performance you install.

Part References & Replacement

1. Start with the marking on the shell. Every reference is stamped on the body; read it in full rather than from memory, including the suffix, because the reference — not the family name — identifies the exact part.
2. Match the series exactly. Y3B has its own body and its own locking geometry. Do not assume a Y3, Y3A, Y11 or Y27 reference will drop into the same opening or mate with the same half; a different prefix means a different connector, not a different grade of the same one.
3. Decide whether you are replacing one half or the pair. If only the plug is worn, the socket it mates with still has to agree, so confirm both references before the order goes in.
4. Check the interface, not only the number. Panel cutout, keying position, cable entry and any backshell or strain relief all have to line up with what is already installed — on an aerospace circular connector installation these are the details that decide whether a part drops in or a panel gets reworked.
5. Photograph the old part if the marking is worn. A clear image of the shell, the keying and the contact face settles most reference questions faster than a description does.
6. Write the reference onto the drawing and the stores label. Repeat orders, spares and second-source comparisons all get quicker once the exact number sits next to the part in your own documentation.

Specifications at a Glance

Field Applications

• Aircraft and avionics wiring. Cockpit panels, flight-control runs and instrument looms use the compact shell and the one-pull release where a technician may have to break a circuit in a confined space; this is the kind of aerospace circular connector that tolerates being handled often.
• Military equipment and field gear. Vehicle wiring looms, portable communication sets and ground support equipment need a plug that stays mated while the platform moves and comes apart quickly when it has to.
• Industrial automation and control cabinets. Robot cells, machine tools and panel builds use industrial circular connectors like these to join a control loom to a drive or a sensor cluster without adding a terminal block.
• Electronic communication equipment. Racks, repeaters and field radio hardware run signal and power through one shell, which keeps the rear of a rack readable and serviceable.
• Test and calibration benches. A connector that mates by feel and releases with one pull is quicker to move between units under test than a threaded coupling.
• Maintenance and spares. MRO teams fit the Y3B into existing Y-pattern builds where the original reference is due for replacement and the wiring should not be reworked.

Ordering & Delivery

1. Send the references and the quantities. Our stock covers the full Y3B range and the wider catalogue of industrial circular connectors, but not every reference is displayed in the digital catalogue — if you cannot find a number, ask and we will confirm it against the model list.
2. Confirm price and lead time with your sales contact. Both are quoted per order rather than held as list figures, because they move with reference, quantity and destination.
3. Say how the parts should arrive. Individual bagging for a production line, kit-packed sets for a field team and bulk cartons for stock are different packing jobs, and the choice is easier at the quotation stage than after the goods are packed.
4. Ask about sample availability if you want to check the mating feel and the shell finish on a bench before committing to a batch.
5. One-stop export service. Export documentation and shipping coordination are handled as part of the order, so the goods move through one process rather than being split between several suppliers.
6. Note the reference for repeat orders. Quoting the same number again is the surest way to receive the same part, and it keeps spares and programme buys aligned with the drawing.

Spares Storage & Handling

• Keep the original packaging until the moment of mating. The bag, the contact protection and any desiccant packed with it exist to hold the gold faces clean and dry; opening a bag early and dropping the connector loose into a drawer removes that protection faster than any service condition will.
• Store dry, and let a cold part reach room temperature before unbagging. Carrying a connector from an unheated store into a warm assembly area pulls condensation onto the plating, so leave it sealed until the shell has warmed, then open it at the bench.
• Keep spares uncoupled and unloaded. Do not leave a spare pair mated in a box and do not hang a cable from a mated pair — the push-pull lock is built to hold under vibration in service, not to carry weight on a shelf.
• Bag shells individually so they cannot rattle together, and keep fingers off the contact faces. Grease from handling and metal swarf from a shared drawer are the two things that turn a low-resistance contact into an intermittent fault; never touch a gold face with a file, emery cloth or a general-purpose oil.
• Label every bag with the full stamped reference and the quantity. Y3B-2004TK5 and Y3B-2004ZJ are the two halves of one connection, and a bag marked only "Y3B" will sooner or later be issued as the wrong half.
• Rotate stock first in, first out. Industrial circular connectors that sit at the back of a shelf for years are the ones that reach the bench with a dulled or corroded shell, so issue the oldest bag first and re-order behind it rather than holding more than the programme actually consumes.
• Inspect before issue, not after installation. Check the keying, the shell mouth and the contact faces; a dented shell or a displaced contact is far cheaper to catch in stores than halfway through a panel build.
• Give field and MRO teams a small sealed kit. One bag per reference per platform keeps a repair moving without breaking into the main stock, and it makes the parts count easy to check when the job is closed out on a military circular connector installation.
• If a contact face has picked up handling marks, clean it with isopropyl alcohol on a lint-free swab and let it dry fully before mating. Do not blow it out with an unfiltered air line — that is how moisture and oil are driven into the insulator.

Technical Support & Model Matching

Specifying the right part is easier with an engineer on the other end of the conversation. Our technical team helps you match a requirement to the correct reference — comparing series, contact count, coupling and mounting style against the drawing or part number you already hold — and works through troubleshooting with you when a mated pair or an installed assembly does not behave as expected. We also advise on installation and commissioning practice, and coordinate sourcing, pre-shipment inspection and export documents through our supplier network, so what arrives matches what was agreed.

FAQ