48-Core GYTA53 Cable Installation for a Telecom Network in Indonesia

In June 2026, SOCT supplied approximately 58 km of 48-core GYTA53 direct buried fiber optic cable for a regional telecommunications backbone project in Indonesia.

The customer, a regional telecom network contractor, was building an underground fiber route of approximately 54 km to connect several network nodes. The proposed route passed through roadside corridors, agricultural land, village sections and several paved crossings.

Because most of the cable would be installed directly in the ground, the customer needed more than a standard outdoor duct cable. The selected cable had to resist moisture, soil pressure, sharp ground materials and rodent activity while remaining practical to handle during trench installation.

SOCT recommended a 48-core GYTA53 double-armored, double-jacket fiber optic cable. The cable supply was combined with project-specific drum planning, optical test records and suitable underground splice protection.

Project Overview

The Customer’s Initial Requirement

The customer initially requested a 48-core underground optical cable for the complete route.

However, “48-core underground cable” was not enough information to confirm the correct product.

Before preparing the cable specification, SOCT reviewed:

• The total route length;
• Direct buried and protected crossing sections;
• Soil and drainage conditions;
• Planned cable joint locations;
• Required drum lengths;
• Rodent and mechanical damage risks;
• Installation equipment;
• Fiber reserve requirements;
• Optical performance requirements;
• Packaging and cable identification.

The route review showed that one installation method would not be suitable for every section.

Most of the network could use direct burial, but paved road crossings, drainage areas and building entry points required protective ducts. The final design therefore combined an armored direct buried cable with local HDPE duct protection.

This avoided the cost and construction work of installing continuous conduit along the entire route while providing additional protection where mechanical risks were higher.

Why GYTA53 Cable Was Selected

SOCT recommended a 48-core GYTA53 double-armored and double-jacket fiber optic cable.

The selected structure included:

• 48 G.652.D single-mode fibers;
• PBT loose tubes;
• Water-blocking filling compound;
• A central steel wire strength member;
• Polymer-coated aluminum tape;
• An inner polyethylene sheath;
• Polymer-coated steel tape armor;
• An outer polyethylene sheath.

The combination of aluminum tape, steel tape armor and two PE jackets made the cable suitable for underground routes requiring additional moisture, crush and rodent protection.

Moisture Protection

The loose tubes and cable core used water-blocking materials to limit longitudinal moisture movement.

The aluminum tape and inner PE sheath created an additional barrier between the cable core and the surrounding environment. This was particularly important for low-lying sections where the trench could be exposed to seasonal moisture.

Mechanical and Rodent Protection

The steel tape armor added resistance against soil pressure, stones, handling damage and rodent activity.

Armor did not eliminate the need for proper trench preparation, but it provided a more suitable structure than a conventional non-armored duct cable for direct contact with underground conditions.

Capacity for Network Expansion

The customer did not plan to activate all 48 fibers during the first project phase.

The additional fibers provided capacity for:

• Current backbone transmission;
• Future network nodes;
• Network protection routes;
• Maintenance reserve;
• Emergency restoration;
• Later network expansion.

G.652.D was selected as the project’s standard single-mode fiber because it is widely used in telecommunications backbone and access networks.

Route Review and Installation Adjustment

The construction team divided the proposed 54 km route into separate installation sections before excavation began.

Each section was reviewed according to:

• Access for excavation equipment;
• Cable drum positioning;
• Road and drainage crossings;
• Existing underground utilities;
• Joint pit locations;
• Soil condition;
• Future maintenance access.

During this review, several paved crossings and water-prone sections were identified as unsuitable for unprotected direct burial.

The installation plan was adjusted so that:

• GYTA53 cable was directly buried along open roadside and agricultural sections;
• HDPE ducts were installed beneath paved crossings;
• Additional conduit protection was used at drainage channels and building entrances;
• Joint pits were moved away from locations exposed to standing water;
• Drum lengths were aligned with the revised splice positions.

This route-specific adjustment prevented the contractor from applying the same construction method to locations with very different mechanical risks.

SOCT’s comparison of direct buried and duct fiber optic cable provides additional information about selecting installation methods for different route conditions.

Project-Specific Drum Planning

The planned network route was approximately 54 km, while the ordered cable quantity was approximately 58 km.

The additional four kilometers were used to cover:

• Cable route variation;
• Joint preparation;
• Reserve loops;
• Equipment-room entry;
• Road crossing allowances;
• Installation tolerance;
• Emergency repair reserve.

SOCT reviewed the planned joint locations and prepared a drum schedule for the construction sequence.

Drum planning considered both cable length and field practicality. A drum that is technically possible to manufacture may still be unsuitable if it cannot be transported to the installation point or safely positioned beside the trench.

Each drum was assigned to a defined route section and identified by:

• Drum number;
• Cable model;
• Fiber count;
• Supplied length;
• Gross and net weight;
• Direction of rotation;
• Corresponding optical test record.

Matching the drums with defined route sections helped reduce unnecessary field joints and improved cable traceability during installation.

Installation Process

1. Route Survey and Utility Identification

Before excavation, the contractor compared the planned route with the actual site conditions.

The route survey identified:

• Existing power cables;
• Water and drainage pipes;
• Road crossings;
• Culverts;
• Property boundaries;
• Soft or waterlogged soil;
• Equipment access points;
• Proposed splice locations.

Mechanical excavation was restricted near existing underground services. Manual or controlled excavation was used where the route approached utilities.

The contractor also recorded sections where the original route required minor adjustment.

2. Trench Preparation

After excavation, the trench was inspected before cable placement.

Large stones, sharp debris and construction waste were removed. Sections with hard or uneven ground received a fine-soil or sand bedding layer to reduce concentrated pressure against the cable jacket.

The team also checked:

• Trench continuity;
• Drainage conditions;
• Sudden level changes;
• Tight direction changes;
• Stability of trench walls;
• Entry points into protective ducts.

The cable route used gradual bends rather than sharp corners. This helped protect the internal cable structure and reduce the risk of additional optical loss.

3. Protective Ducts at High-Risk Locations

HDPE ducts were installed beneath paved roads, vehicle entrances, drainage channels and selected building entry points.

Pulling ropes were placed inside the ducts before cable installation. Duct entrances were checked for sharp edges, and the bend arrangement was reviewed to avoid excessive pulling force.

After cable installation, the duct ends were sealed to reduce the entry of water, soil and debris.

This hybrid approach allowed the project to use direct burial across most of the route while reinforcing locations likely to experience concentrated loads or future excavation.

4. Cable Drum Inspection and Positioning

Before each installation section began, the field team checked the cable drum against the route schedule and packing list.

The inspection covered:

• Drum identification;
• Cable type;
• Fiber count;
• Cable length;
• Wooden drum condition;
• Cable-end sealing;
• Outer jacket condition;
• Factory optical test record.

The drum was positioned so the cable could be paid off in the marked direction.

The cable was not pulled sideways across the drum flange or dragged directly over rocks, concrete edges or road surfaces. Rollers and manual guidance were used at direction changes, duct entrances and exposed surfaces.

5. Cable Laying and Tension Control

Workers were positioned along the trench, at major bends and at duct crossings to maintain controlled cable movement.

The installation was paused if the team observed:

• A cable loop or kink;
• Sudden pulling resistance;
• A blocked duct;
• Uncontrolled drum rotation;
• Contact with a sharp surface;
• Excessive bending;
• Abnormal pulling tension.

The cable was guided into the trench without twisting or forcing it around tight corners.

Although GYTA53 includes steel armor, the armor was not treated as a substitute for controlled installation. Excessive pulling or bending can still damage the cable core or increase optical attenuation.

6. Cable Reserve and Splice Protection

Cable reserve was left at planned splice pits and equipment entry points.

The reserve provided sufficient cable length for:

• Cable preparation;
• Fusion splicing;
• Closure installation;
• Future maintenance;
• Emergency repair.

The reserve loops were arranged without sharp folding or excessive compression.

The project used a 96-core horizontal fiber optic splice closure to protect the underground 48-core cable joints.

The closure provides additional space for organized fiber routing, splice storage and future branching. Its sealed construction makes it suitable for hand holes, ducts and outdoor underground networks.

7. Joint Testing Before Backfilling

Fusion splicing was completed in a controlled field work area.

Each joint was tested before the splice closure and joint pit were permanently closed. This allowed technicians to identify:

• High-loss splices;
• Incorrect fiber connections;
• Fiber breaks;
• Excessive bending near the closure;
• Unexpected reflection events.

Correcting an issue at this stage avoided reopening a completed trench later.

8. Backfilling and Route Records

After the cable and joints were checked, selected fine soil was placed around the cable where required.

Large stones and construction waste were not placed directly against the outer jacket.

Warning tape or protective identification materials were installed above the cable according to the contractor’s civil design. The remaining trench was then backfilled and compacted in controlled layers.

The contractor recorded:

• Cable route;
• Drum number by section;
• Joint coordinates;
• Closure identification;
• Reserve locations;
• Road crossings;
• Duct sections;
• Changes from the original route.

These records were essential because the cable route could no longer be visually followed after the ground was reinstated.

Factory Testing and Pre-Shipment Review

Before shipment, SOCT checked the completed cable against the approved order requirements.

The review covered:

• GYTA53 cable construction;
• 48-core fiber configuration;
• Cable outside diameter;
• Outer jacket condition;
• Meter marking;
• Cable printing;
• Individual drum lengths;
• Cable-end sealing;
• Drum identification;
• Packing-list information.

Each cable drum received optical continuity and attenuation testing.

Drum-specific test records allowed the customer to match the factory test data with each physical cable length during receiving inspection and field testing.

The shipment was prepared after the cable specifications, drum schedule, identification and packaging information had been checked against the approved order.

This case does not include unsupported claims about long-term field operation or repeat orders. The documented acceptance information is limited to cable configuration, manufacturing inspection, factory optical testing and pre-shipment records.

Project Outcome

The project did not rely on the cable armor alone.

Its practical value came from coordinating cable selection with the route conditions and installation process.

The project demonstrated that successful direct buried cable installation depends on both product structure and construction discipline.

A suitable armored cable improves underground protection, but trench preparation, route design, drum planning, bending control, splice testing and controlled backfilling remain equally important.

Information Required for a GYTA53 Project

To prepare an accurate cable recommendation, buyers should provide:

• Required fiber count;
• Total route length;
• Soil and terrain conditions;
• Direct buried and duct sections;
• Road and drainage crossings;
• Groundwater conditions;
• Rodent risk;
• Planned joint locations;
• Maximum drum dimensions;
• Cable reserve requirements;
• Optical specifications;
• Packaging and labeling requirements.

A request that only states “48-core underground cable” is not sufficient to determine whether GYTA53 or another cable structure is more suitable.

Frequently Asked Questions

Why was GYTA53 selected for this telecom route?

GYTA53 combines water-blocked loose tubes, aluminum tape, steel tape armor and double PE jackets. This structure is suitable for underground routes requiring additional moisture, crush and rodent protection.

Why was 58 km supplied for a 54 km route?

The additional cable covered joint preparation, equipment entry, road crossings, reserve loops, route variation, installation tolerance and emergency maintenance.

Can GYTA53 cable also be installed inside ducts?

Yes. GYTA53 can be installed inside protective ducts at road crossings, drainage channels, building entrances and other high-risk locations.

Why were the joints tested before backfilling?

Testing before closing the joint pit allowed technicians to identify and correct splice loss, fiber breaks or connection errors without reopening the completed route.

Does steel armor prevent all underground cable damage?

No. Steel tape improves mechanical and rodent resistance, but correct trench preparation, pulling control, bending radius, backfilling and route documentation are still required.

Planning an Underground Telecom Network?

Send SOCT your route length, fiber count, soil conditions, road crossings, planned joint locations and drum restrictions.

SOCT can support GYTA53 cable configuration, drum planning, optical testing, splice closure matching, export packaging and Order & Project Support.

Contact SOCT Fiber for Order & Project Support