M-Core Cables : Revolutionizing Connectivity
2024-04-27
Blog
Armoured vs Unarmoured Optical Fiber Cable: Which One Should You Use Where?
One of the most common questions buyers ask before placing a fiber order is whether they need armoured cable or whether unarmoured will do. The price difference is significant, and choosing wrong in either direction costs money — over-specifying wastes budget, under-specifying means digging up the route again in two years.
What "Armoured" Actually Means
An armoured optical fiber cable has a metallic layer — usually corrugated steel tape or steel wire — placed between the inner sheath and the outer jacket. The glass fibre inside is identical in both cases. The armour does not improve optical performance; it protects the cable from crushing, rodent attack, and mechanical stress during and after installation.
Unarmoured cable relies only on its polymer jacket and internal strength members (usually FRP or aramid yarn) for protection.
Where Each One Belongs
| Installation | Typical choice | Reason |
|---|---|---|
| Direct burial (no duct) | Armoured | Soil pressure, rodents, and future excavation risk |
| Inside HDPE duct | Unarmoured usually sufficient | Duct provides the mechanical protection |
| Aerial (pole to pole) | Purpose-built aerial cable | Needs tensile strength, not necessarily steel armour |
| Indoor riser / building backbone | Unarmoured | Lighter, easier to pull, better bend handling |
| Industrial floor / heavy traffic areas | Armoured | Crush resistance |
The Rodent Question
Rodent damage is the single most common reason Indian installers move to armoured cable. Rats gnaw through polymer jackets, and a single bite can take down a link. In agricultural belts, older industrial estates, and any route passing through open ground, armoured cable is worth the premium simply for this reason.
That said, armour is not rodent-proof in an absolute sense — it is rodent-resistant. Good duct practice and proper sealing at entry points matter just as much.
The Trade-offs Nobody Mentions
- Weight and bend radius — armoured cable is heavier and stiffer, which makes long pulls and tight corners harder
- Termination time — stripping armour adds labour at every joint and termination
- Earthing — metallic armour must be properly bonded and earthed, which adds a step your installer cannot skip
- Cost — the difference varies by construction and fibre count, so always compare like-for-like specifications rather than headline price
For indoor and duct-protected routes, the extra weight and termination effort often outweigh the benefit. This is where many projects over-specify out of caution and pay for protection they will never use.
A Middle Option: Non-Metallic Armour
Where rodent protection is needed but metallic armour is undesirable — for example in locations where earthing is complicated, or where lightning-prone routes make an all-dielectric design safer — non-metallic (all-dielectric) constructions are available. These use glass yarn or hardened jackets instead of steel. Worth asking about if your route has both rodent risk and earthing constraints.
How to Specify Correctly
When raising an enquiry, share these details and you will get an accurate quote the first time:
- Route type — buried, ducted, aerial, or indoor
- Total length and number of joints expected
- Fibre count and mode (single mode or multimode)
- Environment — rodent-prone, high traffic, chemical exposure, direct sunlight
- Any client or tender specification you must match
FAQ
Does armour affect signal quality?
No. Optical performance is determined by the fibre itself, the splices, and the connectors. Armour is purely mechanical protection. If a link is showing high loss, the cause is elsewhere — splice quality, bend radius violations, or dirty connectors.
Can armoured cable be used indoors?
Yes, and it often is in industrial buildings. Check the jacket material against the fire-safety requirement for the building, since indoor runs may need low-smoke or flame-retardant jackets regardless of armour.
Is armoured cable always more durable?
Against crushing and rodents, yes. But a poorly installed armoured cable — pulled too hard, bent too tight, badly earthed — will fail sooner than a well-installed unarmoured one inside a duct. Installation quality matters more than the cable class.
Talk to the Manufacturer
M-Core Industries manufactures optical fiber cables in both armoured and unarmoured constructions, supplied across India and to more than 27 countries. If you are unsure which construction suits your route, share the site details with our team and we will recommend the right specification rather than the most expensive one. Get in touch here.
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Frequently Asked Questions
What products does M Core manufacture?
M Core manufactures Optical Fiber Cables (OFC), CCTV cables, networking cables, and FRP rods for domestic and international markets.
Does M Core export cables internationally?
Yes, M Core exports its wire and cable products to more than 27 countries worldwide, serving distributors and businesses globally.
Where is the M Core manufacturing facility located?
M Core's manufacturing facility is located in Kundli, Sonipat, Haryana, India.
How can I request a product catalog or quote?
You can download our product catalogs directly from the e-catalogs page, or contact us through the contact page for a customised quote.
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