DE-9 Receptacle for Signal and Low-Power I/O
The Molex 1731090854 is a standard DE-9 (E layout) D-sub receptacle with 9 female socket contacts arranged in 2 rows. It's a through-hole solder-terminated connector from the F, FCT 173109 series, with a white polyester glass-filled housing rated UL94 V-0 and a steel shell with tin plating. This is the receptacle half — mates with any standard 9-pin D-sub plug (male) having the same DE-9 shell size. Typical use is for serial communication ports (RS-232), industrial sensor I/O, PLC interfaces, and instrumentation cabling where a field-serviceable, solderable connector is preferred over crimp-style D-subs.
What the 5 A Rating Means for Real Circuits
Each contact is rated 5 A — that's per-pin current, not total. In practice, if you populate all 9 positions, the combined current heats the connector body, so derate the per-contact current when running more than a few circuits simultaneously. For a typical RS-232 port drawing under 100 mA per line, there's no derating concern. For a low-power sensor bus where each line carries 1-2 A, the 5 A rating gives solid headroom. The machined copper alloy contacts handle repeated soldering and rework on site without losing spring force.
Mounting and Hardware Fit
This receptacle has an unthreaded housing/shell flange — no integrated jackscrew threads. That means you supply your own 4-40 or M3 hardware through the flange holes to secure it to the panel or mating plug. The through-hole solder tails go into a PCB or you can solder wires directly to the pins (solder-cup style termination). The white insulator helps identify this connector in a harness bundle if you're colour-coding signal types.