D-Sub Screw Lock Cable, DB9 DB15 DB25 Serial and I/O Cordset

Overview

A D-Sub screw lock cable exists to fix one specific failure. A plain D-Sub shell is held in its socket by nothing more than the friction of its stamped contacts, and friction is not a retention method. On a bench that is fine; in a CNC cabinet next to a spindle, on a valve manifold bolted to a press, or inside a shipboard console that sees continuous low-frequency vibration, the shell walks out a fraction of a millimeter at a time until you are chasing an intermittent fault that never reproduces on the test bench. This cordset uses shells fitted with #4-40 UNC jackscrews that clamp the connector to the mating hood or panel so it cannot back off. It is built in DE-9, DA-15 and DB-25, straight or right-angle, in either gender, and wired 1:1 or crossed to the pinout you send us.

Choosing between DE-9, DA-15 and DB-25

The naming on this family causes more wrong orders than anything else. In the D-Sub series the letter identifies the shell size and the number gives the contact count, so strictly only the 25-position shell is a “DB”. In practice the trade says DB9 for a nine-pin shell and DB15 for a fifteen-pin one and everyone understands. We accept either notation on an order, but we need three facts: the shell size, the contact count, and whether the shell is standard or high density, because the two are not interchangeable.

The trap sits in the middle of that table: a standard-density DA-15 and a high-density DE-15 are both “fifteen pin”, both fit the same panel cutout, and neither will mate with the other. Standard-density contacts sit on a coarser pitch in two rows; the high-density shell squeezes three rows into the same footprint. Count the rows on the connector face before you order, or photograph it.

What the jackscrews actually do

Two jobs, and the second is the one people forget. First, they pull the plug fully home and hold it there, so the contacts stop fretting and the connection stops being intermittent. Second, they transfer the mechanical load from the contacts to the shell: the weight of the cable, a technician tripping over it, the tug when a cabinet door is closed – all of it lands on the threaded hardware rather than on nine stamped pins. The threads are #4-40 UNC as the series convention, so check that the mating side has matching hardware.

1:1 or crossed: the decision that breaks orders

“DB9 to DB9” is not a finished order. A straight-through 1:1 lead carries every pin to the same pin at the far end; a crossed lead swaps the transmit and receive conductors so two data-terminal devices can talk without an adapter. Null-modem patterns vary between vendors, and a cable that is wrong in this one respect is a perfectly built cable that does not work. Tell us which you need, or photograph both ports.

Key specifications

Straight or right-angle, male or female

A right-angle shell takes the cable away along the panel instead of straight out of it, which is usually what you want in a shallow enclosure or a rack where the door still has to close. We mold both versions in both genders, and mixed builds – male at the controller, female at the device – are routine. Because the hood is molded onto the cable, the flex point sits inside the overmold rather than at the solder cups.

Typical applications for this D-Sub screw lock cable

• RS-232 service and console ports on PLCs, drives and HMIs
• CNC operator panels and machine I/O breakouts
• Valve manifolds and pneumatic terminal blocks bolted to vibrating frames
• POS terminals, receipt printers and weigh scales
• Railway signaling cabinets and shipboard consoles

How to specify your build

1. Shell size and pin count, plus whether it is standard or high density.
2. Gender at each end, and straight or right-angle.
3. Pinout: 1:1, crossed, or a drawing you already have.
4. Shielded or unshielded, and whether the drain is tied at one end or both.
5. Length, and whether the run is inside a cabinet or across a machine.
6. Jacket: PVC for cabinet wiring, PUR where there is oil or coolant.
7. Quantity, and whether this is a prototype or a production order.

Workmanship and testing

IPC/WHMA-A-620 Class 3 is the workmanship bar for D-Sub Screw Lock builds, and ISO 9001 is the system behind the line, from 32 to 12 AWG. Every D-Sub build gets a continuity and pinout check before it is boxed, and seal checking is quoted whenever an ingress rating is on the drawing.

Material declarations against RoHS and REACH are issued per project, alongside the dimensional and electrical reports agreed at quotation; see certifications, compliance and material declarations. Where your drawing names a UL style or another approval, the build follows your drawing and ships with the supporting document rather than a claim of our own. Overmold tooling for this part is designed and cut in our own tool room under the overmold tooling we build in-house, so the tool belongs to your program and a revision is a machining job rather than a new negotiation. Related reading: our build-to-print process.

Custom builds and ordering

Five pieces is the prototype minimum for D-Sub Screw Lock builds, shipping in 3 working days. The production minimum is 500 pcs, delivered 14 working days after approval. Tooling not already held adds around 10 working days. D-Sub orders ship as OEM or ODM under your part number and labeling material certificates and first-article reports come with them on request.

Related D-Sub and screw-lock assemblies

• IP67 D-Sub Screw Cable for outdoor and washdown panels when the panel face sees water
• DB9 RS485 Screw Cable for Modbus RTU multi-drop runs
• DB9 to RJ45 Serial / Console Cable
• DB50 to DB25 DTE Serial Cable
• 2V2 / 3W3 / 5W5 Mixed-Contact D-Sub Cable
• 13W3 to VGA (HD15) Mixed-Contact D-Sub Cable
• Screw Lock Console Cable, DB9 to RJ45 for rack management ports

The interface itself is described in detail on the D-subminiature reference, which covers the shell naming and the contact layouts. Full ranges: Screw-Lock Molded Cable • Signal and Data Cables • Panel Mount Cable.

Frequently Asked Questions