Side-by-Side Comparison
Fiber Connectors
SC vs. ST
Comparing 2 standards across 10 specifications. 9 key differences identified.
Comparing:
SC
ST
The SC connector (Subscriber Connector / Standard Connector, TIA-604-3 / FOCIS-3) is a push-pull optical fiber connector developed by NTT. Utilizing a 2.5 mm ceramic ferrule and a square molded plastic body, it is a primary standard in telecommunications and FTTH GPON/EPON installations.
The ST connector (Straight Tip, TIA-604-2 / FOCIS-2) is a legacy fiber optic connector developed by AT&T Bell Laboratories. Featuring a 2.5 mm spring-loaded ceramic ferrule with a BNC-style twist-and-lock metal bayonet coupling, it remains common in industrial networks and campus multi-mode backbones.
Specification Comparison Table
10 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard / FOCIS
|
TIA-604-3-B (FOCIS-3) / IEC 61754-4 | TIA-604-2-B (FOCIS-2) / IEC 61754-2 |
|
Ferrule Diameter
|
2.5 mm | 2.5 mm |
|
Ferrule Material
|
Zirconia ceramic | Zirconia ceramic or stainless alloy |
|
Latching Mechanism
|
Push-pull snap-in rectangular housing | Bayonet twist-lock (BNC-style keying) |
|
Fiber Modes Supported
|
Single-Mode (OS2) and Multi-Mode (OM1–OM4) | Multi-Mode (OM1/OM2 primarily) and Single-Mode |
|
Typical Insertion Loss
|
0.20–0.30 dB | 0.25–0.40 dB |
|
Polish Types Available
|
UPC (Blue), APC (Green–standard for FTTH PON) | — |
|
Standard Duplex Pitch
|
12.7 mm | — |
|
Polish Type
|
— | PC / UPC (Round metal housing) |
|
Mating Cycles
|
— | 500+ cycles |