TE 1-1734577-4: Shielded Cat3 RJ45 Jack with Green LED
It's a shielded jack — the metal shell wraps the entire body to bleed EMI before it reaches the board traces — and carries a green-green LED pair for link/activity indication on the faceplate. This is the jack you spec when the panel needs a visual link status and the cable run is Cat3 voice or low-speed data.
What Cat3 Rating Means for Your Application
The Cat3 rating sets the frequency ceiling at 16 MHz — fine for 10BASE-T Ethernet and analog phone lines, but not for 100BASE-TX Fast Ethernet (which needs Cat5 at 100 MHz) or gigabit. For a legacy PBX, an intercom system, or a 10 Mb control network, it's a direct fit. The shielded construction helps keep coupled noise off the signal pair in industrial cabinets where VFDs or contactors share the panel.
Green LED and Board Lock — Practical Details
The green-green LED pair means both indicator positions light green when the link is active — no bicolor or amber. If the existing jack in the panel has a green-yellow or green-amber LED, the 1-1734577-4 won't match the blink pattern. The board lock is a pair of plastic pegs that snap into the PCB before reflow or wave solder, keeping the jack square to the board while the solder joints set. On a production line that's a reliability win; in a rework station it means you need to clear the holes before inserting the replacement.
The 1-1734577-4 shares the same shielded vertical body, Cat3 rating, and board lock as the 1734577-4 — the difference is the LED: green-green here versus green-yellow on the 1734577-4. If the BOM specifies a board lock and thick gold for repeated reconnects, the 1-1734577-4 or 1734577-4 are the ones; the 1734577-2 is a cost-reduced variant for single-mate installs.