ADSS εναντίον OPGW: Πώς να επιλέξετε το σωστό καλώδιο ινών κεραίας για τη γραμμή τροφοδοσίας σας

Δύο προτάσεις χωρίζουν αυτά τα καλώδια στην πράξη. Κάποιος κουβαλά το δικό του βάρος και δεν αγγίζει τίποτα ηλεκτρικό. Το ένα αντικαθιστά το καλώδιο γείωσης και γίνεται μέρος του συστήματος γείωσης.

Αν διευκρινίσετε, μεταπωλώ, ή να εγκρίνει ίνες κεραίας για έργα κοινής ωφέλειας και τηλεπικοινωνιών, αυτός ο οδηγός σάς δίνει έναν πίνακα επιλογής τεσσάρων μεταβλητών αντί για μια άλλη λίστα χαρακτηριστικών. Διορθώνει επίσης μια υπόθεση που εμφανίζεται σχεδόν σε κάθε ανταγωνιστικό άρθρο — και στις περισσότερες RFQ που λαμβάνουμε.

Τι πραγματικά διαχωρίζει αυτά τα καλώδια

ADSS σημαίνει All-Dielectric Self-Supporting. Το πλήρως διηλεκτρικό σημαίνει ότι δεν υπάρχει μέταλλο πουθενά στο καλώδιο — η αντοχή προέρχεται από ένα πλαστικό ενισχυμένο με υαλοβάμβακα (FRP) κεντρικό μέλος και νήμα αραμιδίου, την ίδια οικογένεια ινών που χρησιμοποιείται στο βαλλιστικό ύφασμα. Αυτοφερόμενο σημαίνει ότι μεταφέρει το δικό του βάρος μεταξύ πύργων χωρίς ξεχωριστό καλώδιο αγγελιοφόρων.

OPGW σημαίνει Optical Ground Wire. Είναι ένας κλώνος μεταλλικός αγωγός με μια οπτική μονάδα σφραγισμένη μέσα σε ένα σωλήνα από ανοξείδωτο χάλυβα. Κάνει τη δουλειά που κάνει ήδη το εναέριο καλώδιο γείωσης — αναχαίτιση κεραυνών και μεταφορά ρεύματος σφάλματος — και μετακινεί δεδομένα ταυτόχρονα.

Τώρα το κομμάτι που αλλάζει την απόφασή σου:

1. Το ADSS είναι μια προσθήκη στη γραμμή σας. Το OPGW είναι μια αντικατάσταση ενός στοιχείου γραμμής. Κρεμάτε το ADSS σε εφεδρικές θέσεις πύργων. Κατεβάζετε το παλιό καλώδιο γείωσης για να εγκαταστήσετε το OPGW.
2. Μόνο το OPGW μεταφέρει ρεύμα σφάλματος. Έχει βαθμολογία βραχυκυκλώματος. Το ADSS δεν έχει τέτοια βαθμολογία και δεν θα το κάνει ποτέ, γιατί δεν οδηγεί τίποτα.
3. Το ADSS μπορεί συχνά να εγκατασταθεί χωρίς διακοπές. Το OPGW δεν μπορεί σχεδόν ποτέ. Η αλλαγή ενός καλωδίου γείωσης σημαίνει ότι το κύκλωμα κατεβαίνει.

Έλεγχος πραγματικότητας αγοραστή: Όταν ένας προμηθευτής αναφέρει και τις δύο επιλογές, το πρώτο ερώτημα δεν είναι η τιμή. Είναι αυτό: έχει ήδη εναέριο καλώδιο γείωσης αυτή η γραμμή;, και σκοπεύει ο ιδιοκτήτης να το αγγίξει? Αν η απάντηση είναι “Ναί, υπάρχει ένα, και όχι, δεν το αγγίζουμε,” Το OPGW είναι εκτός πίνακα προτού εισέλθει το κόστος στη συνομιλία.

Η υπόθεση Σχεδόν κάθε οδηγός είναι λάθος

Το ADSS δεν είναι ένα προϊόν.

Το ADSS με μονό και διπλό τζάκετ είναι κατασκευασμένο διαφορετικά, φτάνουν σε διαφορετικές αποστάσεις, και να επιβιώσουν σε διαφορετικά κλίματα. Σε ορισμένες μεταβλητές απόφασης, το χάσμα μεταξύ τους είναι μεγαλύτερο από το χάσμα μεταξύ ADSS και OPGW.

Διαβάστε ξανά την πρώτη σειρά. Μια προδιαγραφή γραμμένη από ένα γενικό άρθρο — “Το ADSS εκτείνεται έως 1,000 Μ” — είναι ακριβής για τη μία κατασκευή και λάθος κατά τρεις φορές για την άλλη. Βλέπουμε αυτή τη σύγκρουση σε πραγματικές έρευνες: ένας πελάτης στέλνει α 600 Απαίτηση ανοίγματος m που αναφέρουν μια τιμή μονό τζάκετ που βρήκαν αλλού.

Από εδώ και πέρα λοιπόν, αυτός ο οδηγός αντιμετωπίζει την επιλογή ως τριπλή, όχι αμφίδρομη.

Μεταβλητός 1 — Κατηγορία τάσης και τι απαιτεί η γραμμή

Η κλάση τάσης διαμορφώνει την απόφαση και από τα δύο άκρα: καθορίζει εάν το OPGW χρειάζεται μια συγκεκριμένη ηλεκτρική βαθμολογία, και καθορίζει πόσο σκληρό είναι το περιβάλλον σε ένα μπουφάν ADSS.

Αυτό που μόνο το OPGW φέρνει στο τραπέζι

Επειδή το OPGW αντικαθιστά το καλώδιο γείωσης, κληρονομεί τις ηλεκτρικές υποχρεώσεις αυτού του εξαρτήματος. Δύο αριθμοί διέπουν τις προδιαγραφές, και κανένα δεν έχει ισοδύναμο ADSS:

• Θερμική ικανότητα βραχυκυκλώματος (I²t) — πόση ενέργεια σφάλματος απορροφά το καλώδιο πριν υπερθερμανθεί ο αγωγός και μαγειρευτούν οι ίνες μέσα.
• Αντίσταση DC — το οποίο πρέπει να κάθεται κοντά στο καλώδιο γείωσης στην άλλη πλευρά της γραμμής, ή τα δύο μοιράζονται το ρεύμα άνισα και το ένα τρέχει ζεστό.

Εδώ είναι μια αντιπροσωπευτική διαμόρφωση 48 ινών που κατασκευάζουμε, ώστε να μπορείτε να δείτε πώς μοιάζουν αυτοί οι αριθμοί στην πράξη:

Larger metallic cross-sections raise both the fault rating and the tensile strength. Smaller sections cost less and load the tower less. Your grid operator’s fault study sets the floor.

Distributor’s Talking Points: When a utility customer names a voltage class and stops there, you still cannot quote OPGW. Ask for thefault current and clearing time — those two produce the required I²t — and ask what theexisting ground wire’s DC resistance is. Asking these turns you from a price-taker into a technical counterpart, and it takes one message.

What voltage does to ADSS

ADSS conducts nothing, so voltage does not stress it electrically in the way it stresses a conductor. The stress is on the jacket surface.

Near energised conductors, an electric field forms around the cable. Surface contamination and moisture concentrate that field into small dry patches, and repeated micro-discharges erode polyethylene over time. The failure is slow. It usually appears one to three years after commissioning, which means the buying decision and the consequence are separated by so much time that nobody connects them.

The countermeasure isΣΤΟ (anti-tracking) jacket compound instead of standard PE. We supply both, interchangeably, σε 1.6 mm, 1.8 mm και 2.0 mm wall thicknesses, με 1.8 mm ±0.1 mm as our standard.

Pro Tip for Buyers: Ask your supplier to state, in writing, the jacket compound and wall thickness on the quotation — not just “ADSS cable.” Two quotations that look 15% apart are often a PE-versus-AT difference, and the cheaper line item is only cheaper until the first erosion-driven repair.

A note on selection tables: voltage-class recommendations circulating in the industry reflect common practice, not universal law. Grid codes differ across Latin America, Africa and the Middle East, and the project’s design institute or utility engineering department holds the final say. Treat every table in this guide — including ours — as a starting point for that conversation.

Μεταβλητός 2 — Span Length, and Why One Number Is Never the Answer

Span is where generic articles do the most damage, because they quote a single maximum.

A span figure only means something alongside three other conditions: wind loading, ice loading, and permitted sag. The same cable that comfortably crosses 300 m on a calm plain will not hold the same distance across an exposed mountain ridge with radial ice.

For ADSS specifically, span capability comes from the aramid or polyester yarn strand count and the jacket structure — not from fiber count and not from diameter. That is why span is an engineered parameter you order to, rather than a fixed property you look up.

We build single-jacket ADSS to 100 Μ, 150 Μ, 200 m and 300 m span ratings.300 m is a ceiling, not a target — and it drops when you push fiber count. A 288-fiber single-jacket build, για παράδειγμα, needs the span held to roughly 100 Μ, because the heavier core eats the tension budget.

Distributor’s Talking Points: When a customer says “600 m Span,” three follow-up questions settle the quotation: What is the design wind speed? Is there ice loading? What sag is permitted at the crossing? Without those, any span promise is guesswork — and guesswork is what gets returned.

Μεταβλητός 3 — New Build or Retrofit, and Whether You Can Take an Outage

This variable decides more projects than price does, and it splits cleanly.

New transmission lines

A new line needs a ground wire regardless. The tower is being designed anyway, the loading is being calculated anyway, and the stringing crew is on site anyway. Choosing OPGW at this stage means theincremental cost over a plain ground wire is modest — you are buying fiber, not buying a separate installation programme.

This is the strongest argument for OPGW, and it has nothing to do with the cable being “better.”

Retrofitting a line already in service

Now the arithmetic inverts. Replacing an in-service ground wire with OPGW requires taking the circuit out of service — and the outage is rarely the cheap part.

Real-World Scenario: On a live network, an outage is not a scheduling detail. It goes through a dispatch approval queue, competes with maintenance windows already booked, and may require replacement generation or rerouted load for the duration. Project teams routinely find the outage window harder to secure than the cable is to manufacture. Fifteen working days for cable delivery means very little when the switching request sits in a three-month queue.

ADSS exists largely because of this problem. Because it holds no metal, it can be installed on spare tower positions without becoming part of the electrical system.

On live-line installation specifically: the all-dielectric construction makes it possible in principle. Whether it is permitted onyour line depends on the voltage class, the utility’s live-working procedures, the qualifications of the crew and the asset owner’s authorisation. Treat “ADSS can be installed live” as a question for your utility’s safety authority, not as a specification you can assume. We are happy to supply the cable data your safety case needs; we will not tell you the work is safe on a line we have not seen.

Μεταβλητός 4 — Total Cost of Ownership, Not Price Per Metre

Price-per-metre comparisons between ADSS and OPGW mislead, because the two are not buying the same thing. OPGW’s price includes a ground wire you would otherwise purchase separately. ADSS’s price does not include a ground wire because ADSS is not one.

Four cost blocks belong in a serious comparison. Most published comparisons cover the first and skip the rest.

The tower loading number nobody quotes

Look at that fourth row. At the same 48 ίνες, our OPGW weighs429.64 kg/km against91 kg/km for single-jacket ADSS — roughly 4.7 times heavier — and about 3.4 times heavier than double-jacket ADSS at 128 kg/km.

Commercial Impact: On a new line, the tower is designed for that load and the number is a non-issue. On an older line, it is a structural question that arrives late and costs money — a loading assessment, and sometimes reinforcement. Tower reinforcement does not appear on any cable quotation, which is precisely why it derails retrofit budgets.

Where the double-jacket premium pays back

Paying 20–25% more for a second jacket looks like an easy cut during value engineering. In coastal salt fog, heavy snow or icing conditions, it is the wrong cut.

Single-jacket ADSS isnot suitable for those environments. Salt fog accelerates chemical attack on the jacket; once the jacket is compromised, the aramid underneath loses its protection. Our position is direct: in high salt fog or icing regions, we recommend double-jacket rather than selling a thicker single-jacket as a workaround. The double-jacket construction adds an estimated10 προς την 15 χρόνια of service life in those conditions, alongside better electrical erosion resistance and two-layer water blocking.

We validate this with 720-hour salt spray testing and UV ageing tested to GB/T 18899-2023. Ask any supplier which ageing tests they actually run, and over how many hours.

Putting It Together — The Four-Variable Selection Matrix

Each row below carries a recommendationκαι the condition that overturns it. The overturning condition is the part that matters, because your project will eventually hit one.

The variable this matrix cannot decide for you: fiber count

Almost no buying guide addresses fiber count, yet every purchase order requires the number.

Two principles apply. Πρώτα, build in headroom — utilities that specify only for today’s SCADA and protection traffic tend to return within a few years needing capacity for substation automation, video inspection or telecom backhaul, and a second cable pull costs far more than spare fibers ever did. Γύρω 30% spare capacity is a common planning allowance.

Δεύτερος, respect the trade-off. More fibers means a heavier, thicker cable, which reduces achievable span. Our single-jacket ADSS runs 4 προς την 144 fibers as standard, με 288 available on request when the span stays near 100 Μ. Double-jacket reaches 288 as standard and 576 κατόπιν αιτήματος. OPGW tops out at 96 ίνες.

Pro Tip for Buyers: Decide fiber countπριν you finalise the span rating, not after. Fiber count changes the cable weight, cable weight changes the tension, and tension changes the span the cable can hold. Reversing that order is how projects end up re-ordering.

Field Traps That Appear After the Cable Is Already Hanging

Both cable types have well-documented failure patterns. Neither pattern is really about the cable.

On the ADSS side

• Jacket erosion from the wrong compound. Standard PE in a high-field or high-contamination position degrades. AT compound exists for this reason. The symptom appears years later, far from the purchase decision.
• Aeolian vibration. A light, all-dielectric cable in steady wind oscillates. Without dampers, the fatigue concentrates at the clamps.
• Single-jacket in the wrong climate. Covered above — this is a specification error, not a manufacturing one.
• Fittings assumed to be interchangeable. They are not. Single-jacket and double-jacket ADSS have different outer diameters, so suspension and dead-end clamps sized for one will not correctly grip the other. Budgets that carry the cable price forward but reuse an old fittings line item come up short.

On the OPGW side — where the failures actually cluster

This is the part almost no comparison covers, and it deserves attention.

Field investigations behind published utility installation standards point to the same conclusion: OPGW defects concentrate at thedownlead and splice termination, not in the span. The cable between towers behaves well. The failures happen in the last few metres, where the cable comes down the structure and enters the splice enclosure.

Three mechanisms drive it, and all three are physics rather than local regulation:

• Loss of insulating clearance. Where the downlead is meant to stay clear of the structure, ageing rubber clamps and corroding stainless bands let the cable drift into contact. Discharge erosion follows, and strands break.
• Dissimilar-metal contact. Stainless steel banding against aluminium wire sets up galvanic corrosion. The band fails, then the support fails.
• Ferromagnetic material around coiled slack cable. OPGW carries induced current continuously and fault current occasionally. Coiling slack cable inside a steel storage frame, or binding it with iron wire, behaves like adding core material to a transformer — inter-turn induced voltage rises and burns through strands. Insulating, non-magnetic storage frames and aluminium tape binding avoid it.

Pro Tip for Buyers: When you evaluate an OPGW quotation, look past the cable. Ask what the supplier provides for thetermination package — insulating downlead fasteners, non-magnetic cable storage frames, splice closures, grounding hardware. A cheap cable with an improvised downlead is where the long-term risk sits. We supply the cable and the accessory set — preformed fittings, vibration dampers, grading rings, splice closures and storage racks — under one warranty, specifically so the interface between them is nobody’s grey area.

Bottom Line — Three Questions to Ask Before Anyone Quotes You

Skip the feature comparisons. These three questions resolve most of the decision:

1. Does this line have an overhead ground wire, and will the owner replace it? No → ADSS. Yes → OPGW is genuinely on the table.
2. What is the longest span, and what are the wind and ice conditions there? Πάνω από 300 m rules out single-jacket ADSS immediately. Coastal or icing conditions rule it out at any span.
3. What is in the quotation besides the cable? Jacket compound and wall thickness for ADSS. I²t and DC resistance for OPGW. Fittings, splice closures and downlead hardware for both. Two quotations are only comparable when they contain the same scope.

Manufacturing lead time rarely drives the decision, but it is worth knowing: we stock 12 to 48-fiber ADSS with a 1 km minimum order, and standard OPGW ships at a 3 km minimum with a typical 15 working-day lead time. Outage approval usually takes longer than either.

Not sure which one fits your line? A manufacturer that builds both single-jacket ADSS, double-jacket ADSS and OPGW has no reason to steer you toward one of them. Send us the voltage class, the span profile and whether the line is new or in service, and we will tell you which of the three fits — including when the answer is the cheapest one. Καλώδια ADSS · Καλώδια OPGW

Technical figures in this guide come from our own product specifications and factory testing. Voltage-class and span guidance reflects common industry practice and should be confirmed against the grid code and design standards applicable to your project.