How can you spot the one going to Workshop 1 among a pile of white optical fibers?
In a batch of fiber optic jumpers or sensing cables that are identical in appearance, color (such as white jackets), and diameter, the most standard physical marking method in engineering for quickly and intuitively identifying a specific line (e.g., the fiber optic cable for “to Workshop 1”) at the termination point or patch panel is the use of Fiber Marker Rings.
I. What are Fiber Marker Rings?
A Fiber Marker Ring (also known as a snap-on fiber numbering tube or fiber cable number ring) is a small, insulating accessory specifically designed for physical coding and identity recognition at both ends of optical cables, fiber optic jumpers, and pigtails.
1. Structure and Form
- Snap-on (C-type open ring): Made from elastic engineering plastics (such as modified PP or POM), featuring an opening and anti-slip claws on the side. It can be directly clipped onto the outer jacket of the fiber optic cable at either end after the fiber has been spliced or terminated with an optical connector (e.g., FC, ST, SC, LC), without needing to break the optical path.
- Sleeve-type (Closed ring/Heat-shrink type): This type is slipped onto the outer protective sheath of the fiber optic cable before termination or splicing. It is then fixed at the rear of the connector’s strain relief boot by heat shrinking or mechanical interference fit.
- Common Compatible Cable Diameters: Available in standard specifications according to the outer diameter of the fiber optic cable, such as \Phi 0.9\text{ mm}, \Phi 2.0\text{ mm}, \Phi 3.0\text{ mm}, etc.
2. Coding and Identification Logic
- Digital/Character Combination: The surface of the ring is printed with highly wear-resistant Arabic numerals (0 \sim 9) or letters (A \sim Z). By snapping multiple rings together sequentially (e.g., combining
0+1orW+S+1), a unique line number can be formed at the base of the fiber optic connector. - International Color Code Assistance: Some marker rings are injection-molded according to international color code standards (such as the 10 or 12 basic colors in the TIA-598 specification), enabling dual visual identification of “color + character.”
II. Other General Technical Means for Identifying Fiber Optics in Engineering
If marker rings were not installed during the initial cabling phase, the following general optical tools can be used on-site for line confirmation:
- Visual Fault Locator (VFL):
Inject 650\text{ nm} visible red light into the target fiber optic cable from the equipment room end. Observe at the Workshop 1 end for bright red light output from the connector to verify continuity and route from end to end. - Optical Fiber Identifier:
Utilizes macro-bending principles to clamp onto a single fiber optic cable, sensing the direction and modulation frequency (e.g., 270\text{ Hz}, 1\text{ kHz}, 2\text{ kHz}) of the optical signal transmitted within the core. This confirms whether the fiber optic cable is actively working without interrupting the fiber.
Technical Note: General-purpose fiber marker rings, cable number tubes, tag clips, and red light pens are common ancillary materials and consumables for fiber optic cabling. They are not part of Beijing Dacheng Yongsheng Technology Co., Ltd.'s (OFSCN®) core product line. (OFSCN® focuses on FBG sensing, special high-and-low temperature resistant optical fibers, and metallized seamless steel pipe encapsulated optical fiber cables).