Quick answer: An air blowing micro cable is a small, lightweight fiber optic cable designed to be installed through a compatible microduct with compressed air and a cable blowing machine. The best choice depends on the existing or planned microduct, cable outer diameter, fiber count, loose-tube structure, water protection, strength member, bend limits, blowing equipment, route length, and service environment. Start with the duct and installation method, then select the cable. Do not choose a micro cable from fiber count alone because diameter, weight, surface condition, duct clearance, bends, and cable stiffness directly affect blowing performance.
This guide is for network operators, FTTH planners, outside plant engineers, EPC contractors, distributors, and purchasing teams. It explains how to compare center loose tube and stranded loose tube JET cables, how to confirm microduct compatibility, what to request in an RFQ, and how to reduce installation risk. FiberCableSupplier’s product catalogue identifies JET center loose tube non-metallic air-blowing micro cable and JET stranded loose tube non-metallic air-blowing micro cable. The final model, fiber type, fiber count, and installation limits must always be confirmed against the project data sheet.
Table of Contents
- What Is an Air Blowing Micro Cable?
- Why Use a Microduct Installation System?
- JET Cable Families in the Product Catalogue
- Center Loose Tube vs. Stranded Loose Tube
- How to Match Cable and Microduct
- Fiber Count and Network Planning
- Air-Blowing Installation Checklist
- Testing and Acceptance
- Air Blowing Micro Cable RFQ Checklist
- Frequently Asked Questions
What Is an Air Blowing Micro Cable?
An air blowing micro cable, also called a blown micro cable or microduct cable, is an optical cable engineered for installation into a pre-installed microduct. Instead of pulling the cable through a large conduit with a long pulling rope, the installer uses a blowing machine to feed the cable while high-volume airflow reduces friction and helps move the cable through the duct. The cable still requires controlled mechanical feeding, but the installation force is distributed along the cable rather than applied only at the leading end.
The microduct and the cable work as a system. The duct provides a controlled pathway and contributes to the cable’s long-term protection. The cable must have the right outer diameter, surface, weight, stiffness, tensile handling strength, bend performance, and environmental protection for that pathway. A standard outdoor cable may fit physically but still perform poorly during blowing because it was not designed for the airflow, duct clearance, route bends, and feed equipment used by the project.
ITU-T Recommendation L.108 describes characteristics, construction, and test methods for microduct fiber units and microduct cables used with blowing installation. It also makes an important practical point: test conditions may need to be agreed between the user and manufacturer for the actual installation environment. Read the ITU-T L.108 microduct blowing recommendation together with the project specification, cable data sheet, microduct data sheet, and blowing equipment instructions.
Air blowing micro cable is not the same as an air-blown fiber unit
Purchasers should distinguish a jacketed micro cable from a fiber unit. A micro cable normally has an optical fiber group protected by a loose tube or multiple loose tubes, strength elements, water protection, and an outer sheath. A fiber unit may rely more heavily on the microduct or another housing for mechanical protection. The required product, duct, handling method, and lifetime protection are different, so the RFQ must name the exact product class.
The FiberCableSupplier JET catalogue entries are non-metallic air-blowing micro cables. The center loose tube design uses 250 micrometer fibers in a high-modulus loose tube, water-resistant filling compound, aramid yarn, and an HDPE sheath. The stranded loose tube design uses 250 micrometer fibers in loose tubes, water-resistant filling compound, a central FRP strength member, water-blocking yarn, and an HDPE sheath. These construction details should be compared with the project route and not replaced by a generic label such as “blown fiber.”
Why Use a Microduct Installation System?
Microduct systems are attractive when the network owner wants a small pathway, staged capacity, lower civil-work disruption, or a repeatable route for future cable installation. The duct can be installed as part of a larger civil project, while the optical cable is blown when the service or fiber demand is ready. This can help operators use pathway capacity in phases, but it does not remove the need for careful duct construction and route records.
| Project objective | How a microduct system can help | What the buyer must verify |
|---|---|---|
| Fast deployment in an existing pathway | Uses a prepared microduct instead of opening a large route | Duct continuity, cleanliness, sealing, inner diameter, and route records |
| Phased network expansion | Allows cables to be installed as demand grows | Available spare ducts, access points, bend radius, and future cable sizes |
| Urban or constrained construction | Supports smaller pathways and less disruptive installation planning | Joint quality, water ingress control, pulling chamber layout, and repair access |
| Backbone or access deployment | Supports small cable designs for backbone, access, and FTTH routes | Fiber count, optical budget, splice plan, and outdoor environmental rating |
For a conventional duct, buried, or non-self-supporting aerial route, compare the micro cable with the broader outdoor loose tube fiber optic cable selection guide. A standard GYTA, GYTS, or armored cable may be appropriate for a different route, but it should not be substituted into a microduct system without a verified installation assessment.
JET Cable Families in the Product Catalogue
The catalogue presents two JET families for air-blowing applications. Both use non-metallic construction and HDPE sheathing, but their internal arrangements lead to different design options. The values below are catalogue reference information and should be treated as model-selection inputs, not as a blanket guarantee for every order.
| Catalogue family | Construction summary | Catalogue model range | Typical selection question |
|---|---|---|---|
| GCYFXTY center loose tube non-metallic air-blowing micro cable | 250 micrometer fibers in a high-modulus loose tube, water-resistant filling compound, aramid yarn, HDPE sheath | GCYFXTY-(2-12)C and GCYFXTY-(14-24)C | Is a compact, lower-count micro cable suitable for the duct and access route? |
| GYCFHTY stranded loose tube non-metallic air-blowing micro cable | 250 micrometer fibers in loose tubes, central FRP, water-blocking yarn, HDPE sheath | GYCFHTY-(24-72)C, GYCFHTY-96C, and GYCFHTY-144C | Does the route need a larger fiber count and stranded loose tube structure? |
GCYFXTY center loose tube micro cable
The GCYFXTY family is the compact center loose tube option in the catalogue. The listed fiber count groups are 2 to 12 fibers and 14 to 24 fibers, with catalogue reference cable diameters of approximately 3.5 +/- 0.3 mm and 4.4 +/- 0.3 mm, respectively. The corresponding reference weights are listed as 12 kg/km and 15 kg/km. The catalogue also gives reference tensile, crush, and bending entries for these models.
These values can help a planner make an initial duct-fit comparison, but they are not enough to approve a blowing design. Confirm the exact offered model, tolerance, sheath coefficient, fiber type, installation tension, cable end treatment, and test method. The microduct inner diameter and route geometry must be checked against the final cable diameter, not against a rounded catalogue headline.
GYCFHTY stranded loose tube micro cable
The GYCFHTY family is the higher-count stranded loose tube option. The catalogue lists a 24 to 72 fiber range, plus 96-fiber and 144-fiber models. It identifies loose tubes, fillers where required, a central non-metallic FRP strength member, water-blocking yarn, and an HDPE sheath. The stranded core is designed to provide a compact circular cable while supporting larger fiber counts than the center loose tube models listed in the same section.
A higher fiber count can improve route capacity, but it also changes cable diameter, weight, bend behavior, duct clearance, blowing resistance, and splice planning. The purchase team should request the construction drawing and complete model data instead of assuming that a 96-fiber or 144-fiber cable will work in a duct sized for a smaller cable.
Center Loose Tube vs. Stranded Loose Tube
Both JET constructions are non-metallic, but the selection decision should reflect the network capacity and the installation system. A center loose tube cable can be a good fit for a compact, lower-count access branch. A stranded loose tube cable can be a good fit for a higher-count backbone or feeder route. Neither construction is automatically better; the correct product is the one that fits the duct and satisfies the optical and mechanical requirements.
| Decision factor | Center loose tube JET | Stranded loose tube JET |
|---|---|---|
| Optical arrangement | Fibers housed in one central loose tube | Fibers housed in multiple loose tubes around an FRP strength member |
| Catalogue fiber range | 2 to 12 and 14 to 24 fiber groups | 24 to 72, 96, and 144 fiber models |
| Strength system | Aramid yarn around the cable core | Central FRP with water-blocking yarn around the stranded core |
| Best starting use case | Compact access branches and lower-count microduct routes | Higher-capacity access, feeder, or backbone microduct routes |
| Main checks | Small duct clearance, cable diameter, bend path, and required spares | Duct clearance, route friction, fiber capacity, weight, and splice organization |
| Procurement warning | Do not assume a small diameter means any duct will work | Do not assume high capacity will fit an existing low-capacity duct |
Choose by route role, not only by fiber count
Ask what the cable does in the network. A short access branch may need a small fiber count, repeated installation into narrow ducts, and easy termination at a distribution point. A feeder route may need more fibers, longer route sections, spare capacity, and a clear splice-closure strategy. A backbone route may need even more capacity and a stronger logistics plan for drum lengths, blowing sections, and route restoration.
For downstream organization, plan the transition from the microduct route into a sealed splice enclosure or distribution point. The fiber optic splice closure buying guide can support that part of the bill of materials, while the optical fiber cable distribution box guide is relevant when the access network continues into an FTTH distribution location.
How to Match Cable and Microduct
Microduct matching is the most important part of an air blowing micro cable purchase. Start with the actual microduct inner diameter, material, wall condition, joint type, route length, number of bends, elevation changes, access chambers, and sealing condition. Then compare the cable outer diameter, weight, surface, stiffness, minimum bend diameter, and approved blowing range. A diameter check is necessary but not sufficient.
Check the cable-to-duct clearance
The cable must have enough clearance for airflow and movement through the duct without becoming unstable or jamming at bends. If the cable is too large, airflow may not move effectively around it. If it is too small for the equipment or route, the feed system may not grip it consistently. Use the actual cable diameter tolerance and the actual microduct inner diameter, including the effect of joints, ovality, deformation, temperature, and installed route condition.
Request a compatibility statement that identifies the cable model, microduct inner diameter range, blowing machine, maximum recommended air pressure or flow conditions, feed speed, lubricant if used, and test route. Do not accept a general statement that a cable is “blowable” without a defined system boundary. ITU-T L.108 emphasizes that detailed test conditions can differ by installation environment, so the supplier and user should agree on the relevant conditions.
Review bends, joints, and route sections
- Record the length and location of every microduct section and joint.
- Measure or verify the inner diameter before cable installation.
- Identify sharp bends, vertical rises, changes in direction, and chamber entries.
- Confirm the minimum bend diameter for the cable under loaded and residual conditions.
- Check that the cable can reach the planned splice location with enough protected working length.
- Plan access points so a failed blowing section can be isolated and repaired.
- Keep spare microducts and cable capacity records for future installation.
Use the correct microduct standard references
IEC 60794-5-20 covers outdoor microduct fiber units and related microducts and protected microducts for installation by blowing. The broader IEC 60794-5 sectional specification covers microduct optical fiber cables, microduct fiber units, microducts, and protected microducts for blowing installation in outdoor and indoor applications. Use the applicable standard edition in the contract and ask the supplier to identify the exact product category covered by the offered design.
Fiber Count and Network Planning
Fiber count affects both network capacity and cable selection. Define active services, protection paths, split points, backbone links, access branches, maintenance spares, and future expansion before choosing the model. If the route is difficult to reopen, a reasonable spare capacity may be valuable. However, a larger count can increase diameter and weight, so it must be checked against the microduct and blowing plan.
| Planning input | Question for the network team | Effect on cable purchase |
|---|---|---|
| Current services | How many fibers are required on day one? | Sets the minimum active fiber count |
| Future growth | Will the route serve new subscribers, cells, buildings, or sites? | May justify spare fibers or a larger cable |
| Splicing | Where are branch and repair splices located? | Determines drum sections, working length, and closure capacity |
| Optical architecture | Is the route feeder, distribution, backbone, or point-to-point? | Connects fiber count to equipment and route role |
| Maintenance | How will a damaged section be bypassed or restored? | Influences spare cable, access points, and closure planning |
The catalogue uses 250 micrometer fibers in the listed JET constructions and provides different fiber-count groups for center loose tube and stranded loose tube models. Confirm whether the project requires single-mode or multimode fiber, the relevant optical specification, fiber identification, attenuation limits, proof test, and test wavelength. The word “micro” describes the cable form and installation pathway; it does not determine the fiber type or transmission performance.
After selecting the fiber count, coordinate the optical budget with the equipment, splices, closures, and terminal components. If the route ends at an ODF or distribution box, plan the fiber optic pigtails and splice management at the same time. A cable that fits the microduct but cannot be cleanly organized at the endpoint is not a complete procurement solution.
Air-Blowing Installation Checklist
Good air-blowing results come from preparation, controlled feeding, and documented testing. The cable manufacturer, microduct supplier, and installation contractor should agree on the procedure before the drum reaches site. The FOA installation standard explains that ducts should be tested for sealing and cleaned before blowing, and that machine setup should follow the equipment manufacturer’s instructions. Read the FOA fiber optic installation standard for the broader installation framework.
Before blowing
- Confirm the cable model, fiber count, drum number, drum direction, and cable end labels.
- Inspect the microduct route for blockage, water, damaged joints, sharp bends, and open ends.
- Test continuity, sealing, and route clearance using the project-approved procedure.
- Clean and dry the duct as required by the microduct and equipment instructions.
- Check the cable blowing machine, compressor, feed rollers, seals, pressure controls, and emergency stop.
- Confirm the cable diameter and sheath condition against the machine setup.
- Prepare cable lubricant only if it is approved for the cable sheath, duct material, and project environment.
- Protect the cable drum from dirt, moisture, impact, and uncontrolled payout.
- Confirm the planned blowing length, intermediate access points, and cable reserve at each end.
During blowing
- Feed the cable smoothly and keep the drum payout aligned with the duct entry.
- Control air pressure, airflow, feed speed, and push force within the approved limits.
- Monitor for rising resistance, sheath damage, cable buckling, or sudden speed changes.
- Stop before a problem becomes a permanent cable or duct failure.
- Communicate between the drum, machine operator, route access points, and receiving end.
- Record the start time, stop time, cable length, pressure or flow settings, weather, and any interruption.
- Keep the cable end sealed when the route is not being worked on.
Air blowing is not a license to ignore tensile limits. A machine can feed or push a cable into a duct while the cable is still exposed to local stress at the entry, a bend, a damaged joint, or a blocked section. The installer should use the cable manufacturer’s handling limits and the equipment supplier’s settings, then record deviations for technical review.
After blowing
- Secure and seal both cable ends and protect the working length at the access point.
- Confirm the cable is not under an unintended bend or torsional load.
- Label the cable, duct, route section, drum number, and endpoint.
- Store slack in the planned closure or access arrangement without exceeding the bend limit.
- Complete optical tests before splicing when required by the project procedure.
- Update route drawings, as-built records, fiber schedules, and spare-capacity records.
Testing and Acceptance
Testing should prove both cable condition and route readiness. The exact inspection and test plan belongs in the project contract, but a practical acceptance package may include cable construction inspection, dimensional verification, drum records, fiber continuity, attenuation, OTDR traces, splice loss, sheath inspection, and route documentation. Microduct tests should be recorded separately from optical cable tests because a good cable cannot compensate for a failed pathway.
| Acceptance stage | What to check | Evidence to keep |
|---|---|---|
| Factory | Construction, dimensions, fiber identity, optical performance, and required mechanical or environmental tests | Approved test reports, data sheet, drum number, and packing record |
| Before blowing | Microduct clearance, sealing, cleanliness, continuity, and route condition | Microduct test form, route map, and pre-installation photos |
| During blowing | Pressure, airflow, feed speed, push force, cable length, and interruption events | Machine log, operator record, and incident report if required |
| After blowing | Fiber continuity, attenuation, OTDR, cable ends, labels, and storage condition | OTDR traces, power-meter results, as-built drawing, and fiber schedule |
| After splicing | Splice loss, closure sealing, route identification, and service continuity | Splice report, closure record, final test baseline, and handover file |
Use a baseline approach. Test the cable drum or factory sample according to the project procedure, then compare the installed trace with the baseline after blowing and after splicing. An unexplained change should be investigated before the route is accepted. Keep the cable and microduct records together so a future fault team can identify the route, product model, drum section, access point, and original test result.
Air Blowing Micro Cable RFQ Checklist
A complete RFQ prevents suppliers from quoting different products under the same word “micro cable.” Include the following information in the request:
| RFQ section | Information to provide or request |
|---|---|
| Application | Backbone, feeder, access, FTTH, urban upgrade, long route, or another defined use |
| Cable family | Center loose tube or stranded loose tube; state whether the request is for GCYFXTY or GYCFHTY family |
| Fiber | Fiber type, count, optical limits, color code, identification, proof test, and spare requirement |
| Construction | Loose tube material, filling compound, aramid or FRP strength member, water-blocking system, sheath material, and cross-section |
| Dimensions | Nominal and maximum outer diameter, tolerance, weight, minimum bend diameter, and cable end design |
| Microduct | Inner diameter, material, route length, joint type, bends, chambers, installation condition, and spare ducts |
| Blowing system | Machine model, feed method, compressor, pressure or flow range, lubricant policy, and test route |
| Environment | Temperature, moisture, water exposure, direct-buried or duct condition, UV exposure, and storage requirements |
| Quality | Applicable ITU-T, IEC, utility, or project requirements; factory tests; sample tests; and site acceptance tests |
| Logistics | Drum length, delivery sequence, packing, labels, spare cable, replacement policy, and technical support |
Questions for the supplier
- Which exact model and construction are you offering?
- What are the nominal and maximum cable diameters, weights, and tolerances?
- Which microduct inner diameter range was used for the blowing test?
- What route length, bend schedule, machine, airflow, pressure, and feed speed were used?
- What are the permitted installation temperature, bend diameter, and handling limits?
- Can you provide the full construction drawing and model-specific reference values?
- How are fibers identified, tested, and recorded on each drum?
- Which water-blocking, sheath, and environmental tests apply to the offered cable?
- What splice closure, distribution box, and accessories are compatible with the cable?
- What technical support is available during the first site blowing trial?
Final Recommendation
The right air blowing micro cable is a complete system decision. Match the JET cable construction to the microduct, route, fiber plan, machine, environment, and acceptance procedure. Use GCYFXTY center loose tube models when a compact lower-count design meets the route requirements, and consider GYCFHTY stranded loose tube models when the project needs the higher fiber-count range shown in the catalogue. Confirm every model-specific value before purchase.
FiberCableSupplier’s catalogue includes JET center loose tube and stranded loose tube non-metallic air-blowing micro cables for backbone, access, and FTTH applications. For a project quotation, send the microduct inner diameter, route schedule, cable length, fiber count, fiber type, blowing equipment, and installation environment through the FiberCableSupplier contact page. For the broader product range, review the fiber optic cable product category and the outdoor telecom cabling solutions page.
Frequently Asked Questions
What is an air blowing micro cable?
An air blowing micro cable is a small optical cable designed to be installed through a compatible microduct using controlled airflow and a cable blowing machine. Its outer diameter, weight, surface, strength member, bend performance, and sheath must match the duct and installation system.
What is the difference between a micro cable and a fiber unit?
A jacketed micro cable normally includes an optical fiber group, loose tube or tubes, strength elements, water protection, and an outer sheath. A fiber unit may rely more heavily on the microduct or another housing for mechanical protection. Confirm the required product category before ordering.
What is the difference between GCYFXTY and GYCFHTY micro cable?
GCYFXTY is the center loose tube non-metallic JET family listed for 2 to 12 and 14 to 24 fiber groups. GYCFHTY is the stranded loose tube non-metallic JET family listed for 24 to 72, 96, and 144 fiber models. The internal structure, cable diameter, weight, and fiber capacity must be confirmed for the exact model.
How do I choose the correct microduct size?
Compare the actual microduct inner diameter with the cable’s nominal and maximum outer diameter, then review route bends, joints, ovality, temperature, airflow, machine settings, and the supplier’s blowing test. A simple diameter check cannot prove that a cable will blow successfully through the complete route.
Can I pull an air blowing micro cable instead of blowing it?
Do not assume that a cable designed for blowing should be installed by pulling. The cable and microduct system have defined handling and tensile limits. If an alternative installation method is required, obtain written approval from the cable manufacturer, confirm the pulling calculation, and update the installation procedure.
What should be tested before blowing?
Test the microduct for continuity, clearance, cleanliness, sealing, and route condition using the project procedure. Inspect the cable drum, model, diameter, labels, end protection, and sheath. Confirm the blowing machine setup, compressor, feed rollers, seals, and emergency controls before starting.
How should the installed micro cable be accepted?
Acceptance may include visual inspection, fiber continuity, attenuation, OTDR traces, splice loss, cable-end protection, closure sealing, labels, and as-built records. Compare installed results with the approved baseline and investigate unexplained changes before service handover.
Related Fiber Optic Cable Guides
- Outdoor Loose Tube Fiber Optic Cable Buying Guide for conventional duct, burial, and aerial route selection.
- Fiber Optic Splice Closure Buying Guide for protecting route splices and cable transitions.
- Optical Fiber Cable Distribution Box Buying Guide for FTTH access distribution planning.
- Fiber Optic Pigtail Buying Guide for splice and termination planning.
For a project-specific air blowing micro cable quotation, send the microduct details, route schedule, fiber plan, and installation conditions through the company contact page.