Fujikura 66S Optical Fiber Splicer Single Fiber Fusion Splicer

The Fujikura 66S is a specialized and highly regarded ribbon fiber fusion splicer from Fujikura's acclaimed FSM-60S series. It was designed for high-volume, high-efficiency splicing of fiber optic ribbons, making it an essential tool for the core of FTTX and telecommunications backbone networks during its era.

1. Review & Historical Significance

The FSM-66S is not a single-fiber splicer like the 62S or 50S. Its sole purpose is to fusion splice ribbon fiber, which contains 4, 8, 12, or more fibers in a flat, arrayed structure.

Era: Late 2000s - Early 2010s. Now discontinued and obsolete, but remains a sought-after machine on the secondary market for specific projects.

Status: No longer manufactured or officially supported by Fujikura. Replacement parts are becoming scarce.

Legacy: It was the workhorse for major network build-outs. Its ability to splice an entire 12-fiber ribbon in a single cycle (under 2 minutes for splice and protect) dramatically improved deployment speed and reduced labor costs. It represented the pinnacle of dedicated ribbon splicing technology before multi-functional splicers became more dominant.

Key Innovation: Advanced, automated handling of ribbon fiber, including precision fiber-holding clamps, a dedicated ribbon heater (FHU-40/50), and software capable of analyzing and aligning multiple fibers simultaneously.

2. Performance & Technical Specifications

The 66S's performance is measured by its ribbon splicing capability, not individual fibers.

Alignment Method: Ribbon Core Alignment. It used sophisticated optics and software to image and align the entire ribbon structure, ensuring all fiber cores are aligned simultaneously before a mass fusion splice.

Average Splice Loss: Excellent for ribbon fiber. Typically < 0.07 dB per splice for standard single-mode ribbon (G.652), with very low variation across all fibers in the ribbon.

Splice Cycle Time: The entire process for a 12-fiber ribbon (preparation, cleaving, splicing, and protecting with a ribbon sleeve) could be completed in under 2 minutes. The actual fusion process for the entire ribbon was comparable to splicing a single fiber.

Heater Time: Used a dedicated Ribbon Heater (FHU-40 or FHU-50). Heating time for a ribbon protector was approximately 60-70 seconds.

Display: A large, high-resolution monochrome LCD screen with a user-friendly menu system navigated by physical buttons and a central jog dial.

Power Source: Utilized high-capacity lithium-ion battery packs (e.g., FSB-35/36 series), offering a full day of ribbon splicing on a single charge. Featured hot-swappable capability.

Robustness: Built to a very high standard for demanding central office and field deployment environments. Heavier and more robust than single-fiber splicers.

3. Model Variants & Listing

The "66S" typically refers to the core unit. Different kits and compatible heaters defined the package.

Model / Component Name Key Description & Purpose

FSM-66S The core ribbon fusion splicer unit. This is the main device.

FHU-40 Ribbon Heater The dedicated heater unit for mass protecting ribbon splices with ribbon sleeves. Often sold as a separate module that connected to the 66S.

FHU-50 Universal Heater A newer, faster heater compatible with the 66S and other 60S-series splicers. Could handle both single-fiber and ribbon sleeves.

FSM-66S "M" Package A Full Maintenance Kit. Included the FSM-66S splicer, FHU-40/50 heater, a large hard case, multiple batteries, a full suite of ribbon preparation tools (strippers, cleavers, scribers), and accessories.

FSM-66S "C" Package A more Compact Kit with essential tools only, often for users who already had a base of equipment.

Critical Consumables: Key consumable parts included specialized Ribbon Electrodes and Ribbon V-Grooves (FSU-045R). Sourcing these new is now very difficult.

4. Comparison with Other Splicer Types

Feature Fujikura 62S (Single-Fiber) Fujikura 66S (Ribbon) Modern Splicer (e.g., Fujikura R9)

Primary Use Single Fibers Ribbon Fibers Single & Ribbon (Multi-Function)

Fibers per Cycle 1 12 (or 4, 8) 1 or 12 (with accessory kit)

Splice Speed (12f) ~15-20 min < 2 min ~90 sec

Efficiency Low for ribbons Extremely High for ribbons High for both

Deployment Access, Repair Network Backbone, FTTX Core Universal

Conclusion:

The Fujikura FSM-66S was a highly specialized, ultra-efficient powerhouse for ribbon fiber splicing. For its intended purpose, it was unmatched in speed and reliability, making it a legendary machine for large-scale network construction.

However, its obsolescence and lack of support are critical drawbacks. Furthermore, the industry has largely moved towards multi-function splicers (like the Fujikura R9 or R12), which can splice both single fibers and ribbons with optional accessories. These modern machines offer color touchscreens, cloud connectivity, and support, making the dedicated 66S a relic of a past era, albeit a highly capable and respected one.

Its value today is limited to the used market for specific contractors who still maintain a large inventory of ribbon-based infrastructure and have a source for old consumables. For any new deployment, a modern multi-function splicer is a far more practical and future-proof investment.