


4GAX181 & Floating Neutrally Buoyant Fiber-Optic / Electro-Optical ROV Tether Cable
Neutrally buoyant and floating all-dielectric fiber-optic and high-voltage electro-optical ROV tether cables: 4GAX181 (2 × 9/125 SM + 2 × 50/125 MM fibers in gel-filled PBT tube, LCP braid, 320 kg breaking load, Ø 5.00 mm, 0 kg/km in fresh water / -1 kg/km in seawater), NB-FO30 ultra-slim 3.0 mm optical tether (-0.3 kg/km, 1.8 kN), NB-OE110 11.0 mm O/E composite tether (-2 kg/km, 1.8 kN) and REF 50899 / REF 51332 1,500–2,400 V floating ROV hybrid tethers (1,000–2,300 daN).
Long-excursion inspection ROVs, autonomous/tethered underwater drones, bomb-disposal vehicles and mine-countermeasure (MCM) ROVs require multi-gigabit optical bandwidth without the submerged weight penalty of steel-armoured umbilical cables. The 4GAX181 and Floating Neutrally Buoyant Fiber-Optic / Electro-Optical ROV Tether family spans ultra-light all-dielectric optical tethers (Ø 3.0 mm to 5.0 mm) through 1,500–2,400 V floating electro-optical power tethers (Ø 11.0 mm to 15.0 mm).
For multi-protocol all-optical telemetry, 4GAX181 houses two 9/125 µm single-mode fibers (< 1.0 dB/km at 1310/1550 nm) and two 50/125 µm multimode fibers (< 3.5 / < 1.5 dB/km at 850/1300 nm) in a gel-filled PBT loose tube, reinforced by an LCP yarn braid (320 kg breaking load; 80 kg working load) and yellow foamed TPR / PUR sheaths (Ø 5.00 mm, 19 kg/km air, 0 kg/km fresh water, -1 kg/km seawater, s.g. 0.97). For micro-drones, NB-FO30 reduces diameter to 3.0 mm (-0.3 kg/km in water, 1.8 kN breaking load, 3.0 MPa).
When high-voltage vehicle power must travel alongside optical fibers in a floating profile, NB-OE110 (Ø 11.0 mm, -2 kg/km, ≤ 30.1 Ω/km), REF 51332 (1,500 V, 3×0.60 mm² + 2×2×0.34 mm² + 2×62.5/125 MM, 1,000 daN, s.g. 0.92) and REF 50899 (2,400 V, 3×0.93 mm² + 1×0.22 mm² + 3×9/125 SM, 2,300 daN, -4 kg/km in seawater) deliver zero-drag power and fiber telemetry.
Specify the model (4GAX181, NB-FO30, NB-OE110, REF 50899 or REF 51332), fiber type and spool length in your inquiry. TEBAOFLEX supplies custom lengths from a 50 m minimum order quantity with a standard lead time of 7–45 working days.
Explore the marine, offshore and underwater cable range for related configurations.
For related buoyant ROV tethers and compact electro-optical subsea cables, compare: DLRB-3TP6C & GAX Series Neutrally Buoyant Multi-Pair & Power ROV Tether Cable (250 V) (copper multi-pair and 250 V power neutrally buoyant ROV tethers for medium-range excursions); Compact Hybrid Fiber Optic Power Cable (compact non-buoyant hybrid fiber-optic and power cable for high-density subsea interconnects). Verify single-mode or multimode fiber count, optical attenuation at 1310/1550 nm, and specific gravity.
Construction
The representative construction illustrates 4GAX181 4-Fiber Hybrid SM/MM Neutrally Buoyant ROV Tether Cable: two 9/125 µm single-mode fibers and two 50/125 µm multimode fibers protected inside a central gel-filled PBT buffer tube, wrapped with a high-tenacity LCP liquid-crystal polymer yarn braid (320 kg breaking load), a closed-cell yellow foamed TPR buoyancy inner sheath, and a yellow hydrolysis- and UV-resistant polyurethane outer sheath (Ø 5.00 mm).

| Component | Material and construction |
|---|---|
| Optical fiber package | 4GAX181: 2 × 9/125 µm SM + 2 × 50/125 µm MM fibers in gel-filled PBT loose tube. NB-FO30 & NB-OE110: 9/125 µm SM fibers (≤ 0.4 dB/km at 1310 nm). REF 50899: 3 × 9/125 µm SM tight-buffered. REF 51332: 2 × 62.5/125 µm MM loose-tube. |
| Power & signal conductors (electro-optical models) | NB-OE110: copper power/signal cores (≤ 30.1 Ω/km). REF 50899: 3 × 0.93 mm² tinned Cu (2,400 V, ≤ 22.7 Ω/km) + 1 × 0.22 mm² (100 V, ≤ 91.7 Ω/km). REF 51332: 3 × 0.60 mm² alloy (1,500 V, ≤ 48 Ω/km) + 2 × 2 × 0.34 mm² pairs (≤ 84 Ω/km) + overall Al/PET shield. |
| Tensile fiber reinforcement | Non-metallic high-modulus LCP or aramid braided strength member rated at 1.8 kN / 184 kg (NB-FO30 & NB-OE110), 320 kg / 80 kg SWL (4GAX181), 1,000 daN (REF 51332) or 2,300 daN (REF 50899). |
| Buoyancy inner sheath | Closed-cell yellow foamed thermoplastic rubber (TPR) on 4GAX181 or low-density cellular polyolefin sheath on REF 50899 / REF 51332 tuned for 0.92–0.98 specific gravity. |
| Outer protective jacket | Hydrolysis- and UV-resistant yellow polyurethane (PUR) outer sheath on 4GAX181 (Ø 5.00 mm) or low-density abrasion-resistant polyolefin/elastomer sheath on floating hybrid models. |
Applications
Choose 4GAX181 or NB-FO30 for battery-powered or TMS-tethered ROVs needing a tiny, drag-free optical tether, or select NB-OE110, REF 50899 and REF 51332 for surface-powered long-tunnel and mine-clearance ROVs.

- Observation-class and work-class ROV fly-out tethers requiring simultaneous 9/125 µm single-mode (long-haul Gigabit/CWDM) and 50/125 µm multimode (legacy sonar/video mux) fibers in one 5.0 mm cable (4GAX181).
- Ultra-lightweight battery-powered underwater drones, AUV/ROV hybrid vehicles and deep-tunnel inspection robots using 3.0 mm NB-FO30 optical tether.
- Naval bomb-disposal ROVs (REF 50899, 2,400 V, 2,300 daN) and mine-clearance ROVs (REF 51332, 1,500 V, 1,000 daN) requiring high-voltage power transmission in a floating non-magnetic cable.
- Hydroelectric headrace tunnel, subsea pipeline and potable water aqueduct inspections over multi-kilometre horizontal excursions.
For complete tether management system (TMS) engineering and heavy main lift umbilicals, consult: Custom Subsea & Marine Cable Manufacturer (custom subsea electro-optical and buoyant cable manufacturing capabilities); Heavy-Duty ROV Main Tether & Seabed Trencher / Plough Umbilical Cable (250 V–3 kV) (250 V to 3 kV heavy-duty ROV main tethers and seabed trencher umbilicals). Coordinate excursion tether buoyancy, aramid termination hardware, and rotary optical slip-ring compatibility.
Specifications
| Parameter | Value |
|---|---|
| Series models | 4GAX181 (4F SM+MM), NB-FO30 (Type 3.1 Optical), NB-OE110 (Type 3.2 O/E), REF 50899 (2.4 kV O/E), REF 51332 (1.5 kV O/E) |
| Optical fiber counts & types | 4GAX181: 2×SM 9/125 + 2×MM 50/125; NB-FO30/OE110: SM 9/125; REF 50899: 3×SM 9/125; REF 51332: 2×MM 62.5/125 |
| Optical attenuation | 4GAX181 SM < 1.0 dB/km (1310/1550 nm), MM < 3.5 / < 1.5 dB/km (850/1300 nm); REF 50899 SM 0.40 / 0.25 dB/km |
| Electrical voltage rating (hybrid models) | All-dielectric (4GAX181, NB-FO30); 250–600 V (NB-OE110); 1,500 V (REF 51332); 2,400 V / 100 V (REF 50899) |
| Nominal outside diameter | 3.0 mm (NB-FO30), 5.00 mm (4GAX181), 11.0 mm (NB-OE110), 14.0 mm (REF 51332), 15.0 mm max (REF 50899) |
| Weight in water & specific gravity | 4GAX181: 0 kg/km fresh / -1 kg/km sea (s.g. 0.97); NB-FO30: -0.3 kg/km; NB-OE110: -2 kg/km; REF 50899: -4 kg/km (s.g. 0.98); REF 51332: s.g. 0.92 |
| Breaking strength & working load | 1.8 kN (NB-FO30/OE110); 320 kg / 80 kg SWL (4GAX181); 1,000 daN (REF 51332); 2,300 daN (REF 50899) |
| Bending radius & operating temp | 4GAX181: 40 mm static / 75 mm dynamic (-30 to +80 °C); REF 51332: ≥ 170 mm (-30 to +80 °C); REF 50899: ≥ 250 mm (-10 to +70 °C) |
| Commercial supply terms | Minimum order quantity 50 m; manufacturing lead time 7–45 working days |
| Model designation | Optical fiber configuration | Electrical conductors & voltage | Nominal OD (mm) | Weight air / fresh / sea (kg/km) | Specific gravity / pressure | Breaking / working load | Min. bend radius static / dynamic (mm) |
|---|---|---|---|---|---|---|---|
| NB-FO30 (Type 3.1) | SM 9/125 µm Optical Fiber | All-dielectric (none) | 3.00 | 7.0 / -0.1 / -0.3 | Buoyant / ≥ 3.0 MPa | ≥ 1.8 kN (184 kg) | 15 / 30 |
| 4GAX181 | 2 × 9/125 SM + 2 × 50/125 MM (PBT tube) | All-dielectric (none) | 5.00 | 19 / 0 / -1 | 0.97 kg/dm³ | 320 kg / 80 kg SWL | 40 / 75 |
| NB-OE110 (Type 3.2) | SM 9/125 µm Optical Fiber | Power + Signal Cu (≤ 30.1 Ω/km) | 11.0 | 100 / -1 / -2 | Buoyant / ≥ 2.0 MPa | ≥ 1.8 kN (184 kg) | 55 / 110 |
| REF 51332 (Mine ROV) | 2 × 62.5/125 µm MM Loose Tube | 3×0.60 mm² (1,500 V) + 2×2×0.34 mm² | 14.0 ± 0.5 | Floating / < 0 in sea | 0.92 in seawater | 1,000 daN (10 kN) | 85 / 170 |
| REF 50899 (EOD ROV) | 3 × 9/125 µm SM Tight-Buffered | 3×0.93 mm² (2,400 V) + 1×0.22 mm² (100 V) | 15.0 max | Floating / -4 in sea | 0.98 in seawater | 2,300 daN (23 kN) | 125 / 250 |
| Model & sub-element | Fiber / conductor spec | Attenuation / DC resistance | Operating wavelength / voltage | Buffer / insulation material | Strength & jacket construction | Operating temp (°C) |
|---|---|---|---|---|---|---|
| 4GAX181 — SM Fibers | 2 × 9/125 µm Single-Mode | < 1.0 dB/km | 1310 nm & 1550 nm | Gel-filled PBT loose tube | LCP braid + Foamed TPR + Yellow PUR | -30 to +80 |
| 4GAX181 — MM Fibers | 2 × 50/125 µm Multimode | < 3.5 dB/km / < 1.5 dB/km | 850 nm / 1300 nm | Gel-filled PBT loose tube | LCP braid + Foamed TPR + Yellow PUR | -30 to +80 |
| NB-FO30 — Optical Core | 9/125 µm Single-Mode | ≤ 0.40 dB/km | 1310 nm | Buffered optical core | Tensile strength fiber + dual sheath (3.0 MPa) | -30 to +80 |
| NB-OE110 — Optical Core | 9/125 µm Single-Mode | ≤ 0.40 dB/km | 1310 nm | Buffered optical core | Tensile strength fiber + buoyant sheath (2.0 MPa) | -30 to +80 |
| NB-OE110 — Copper Cores | Stranded copper power/comms | ≤ 30.1 Ω/km at 20 °C | IR ≥ 1,000 MΩ·km (500 V DC) | Polymeric insulation | Shared 11.0 mm buoyant O/E assembly | -30 to +80 |
| REF 50899 — SM Fibers | 3 × 9/125 µm Single-Mode | 0.40 dB/km / 0.25 dB/km | 1310 nm / 1550 nm | Tight-buffered optical core | 2,300 daN fiber braid + polyolefin sheaths | -10 to +70 |
| REF 50899 — HV Power | 3 × 0.93 mm² flexible tinned Cu | ≤ 22.7 Ω/km at 20 °C | 2,400 V working voltage | Special polyolefin insulation | 2,300 daN fiber braid + polyolefin sheaths | -10 to +70 |
| REF 50899 — Control Core | 1 × 0.22 mm² flexible plain Cu | ≤ 91.7 Ω/km at 20 °C | 100 V working voltage | Special polyolefin insulation | 2,300 daN fiber braid + polyolefin sheaths | -10 to +70 |
| REF 51332 — MM Fibers | 2 × 62.5/125 µm Multimode | 1.1 dB/km | 1300 nm | Loose tube with water-blocking | Al/PET shield + 1,000 daN fiber braid | -30 to +80 |
| REF 51332 — HV Power | 3 × 0.60 mm² flexible special alloy | ≤ 48.0 Ω/km at 20 °C | 1,500 V working voltage | Special polyolefin insulation | Al/PET shield + 1,000 daN fiber braid | -30 to +80 |
| REF 51332 — Signal Pairs | 2 × 2 × 0.34 mm² special alloy pairs | ≤ 84.0 Ω/km at 20 °C | Control & telemetry voltage | Pair-sheathed polyolefin | Al/PET shield + 1,000 daN fiber braid | -30 to +80 |
All five models are non-metallic armoured (LCP or high-tenacity aramid/synthetic fiber braid), eliminating magnetic signature and corrosion while maintaining positive or neutral buoyancy.
Hydrostatic pressure resistance is tested to ≥ 3.0 MPa (300 m) on NB-FO30 and ≥ 2.0 MPa (200 m) on NB-OE110 in accordance with marine buoyancy tether qualification procedures.
4GAX181 combines both 9/125 µm single-mode and 50/125 µm multimode fibers in a single 5.00 mm gel-filled PBT loose tube so operators can upgrade from multimode to single-mode optical slip rings without re-cabling.
Standards
| Standard or specification | Application |
|---|---|
| ITU-T G.652 / G.657 & IEC 60793-2-50 | 9/125 µm single-mode optical fiber dimensional, macrobending and attenuation specifications. |
| IEC 60793-2-10 | 50/125 µm and 62.5/125 µm graded-index multimode optical fiber specifications. |
| IEC 60794-1-21 & IEC 60794-1-22 | Optical fiber cable mechanical tensile, crush, cyclic flexing and hydrostatic test procedures. |
| DIN VDE 0207-20 / EN 50363-10-2 | Hydrolysis- and UV-resistant polyurethane (PUR) outer sheath specifications. |
ITU-T G.652 / G.657 Optical Fiber Standards at ITU
IEC 60793 & IEC 60794 Fiber Optic Cable Standards at IEC Webstore
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