AllFiber → Field guides → AFL fiber cable configurations

AFL fiber cable configurations: read the family first

AFL fiber cable configurations depend on the product family, and AFL's own spec sheets show how far apart they are. LE Series loose tube cable puts 12 fibers in each buffer tube at lower counts and 24 per tube at higher counts, and the switch point changes with the jacket: the single-jacket 144-fiber build is 6 tubes of 24, while the double-jacket 144-fiber build is 12 tubes of 12. AFL Hyperscale's Multi Loose Tube (MLT) cable uses 12-fiber tubes. Wrapping Tube Cable (WTC) with SpiderWeb Ribbon (SWR) has no buffer tubes at all. So the fundamentals come down to three checks: which family, which part number, and what holds the fibers.

Three AFL families, three ways to count

Most techs learn one layout and assume the rest of a catalog follows it. AFL shows why that habit fails. Here's what AFL's published sheets say about the three families the color codes hub lists for AFL:

LE Series loose tube: the jacket changes the tube math

The LE Series is a stranded loose tube design, with gel-filled tubes SZ stranded for mid-span access. Both LE sheets list TIA-598-D as the fiber standard. The ordering table is what trips people up.

On the single-jacket (SJ) sheet, 12 through 96 fibers run 12 per tube, and low counts carry fillers: 12F is one tube with 4 fillers, 48F is four tubes with one. At 144F the table jumps to 6 tubes of 24, and 192F through 288F stay at 24 per tube.

The double-jacket (DJ) sheet keeps 12 per tube much longer. Its 144F build is 12 tubes of 12 with no fillers, and its 216F build is 18 tubes of 12. Only 288F and 432F go to 24 per tube.

That difference moves fibers. Take fiber 47 on a 144-count cable. With 12 per tube it sits in tube 4 (brown), position 11. With 24 per tube it sits in tube 2 (orange), position 23. “AFL 144-count” doesn't tell you which build you're holding. The spec sheet does. If you've ever opened one expecting 12 tubes, found six, and suspected the chart, you were right to stop.

Don't decode the build from the part number letters, either. The codes don't follow a pattern you can safely reverse-engineer in a vault. Read the tubes/fibers column for the exact part number on the reel tag or sheath print.

One honest gap: neither LE sheet prints how fibers 13 to 24 are marked inside a 24-fiber tube. TIA-598-D's convention is the base colors repeated with a black tracer, and fiber 20 as black with a white tracer, though the standard lets a manufacturer and buyer agree on another tracer color. That's a starting point, not a guarantee, so look at fiber 13 before you rely on it at speed.

Hyperscale MLT: 12-fiber tubes and fillers

AFL Hyperscale's datasheet for the 108F to 144F internal/external MLT describes a 12-element cable with up to 144 fibers in 12-fiber gel-filled loose tubes, with fillers where appropriate. It lists color-coded fibers and tubes.

That makes it the simplest of the three to count, with two caveats. The datasheet doesn't print the color order, and below 144F some of the 12 positions are fillers. Counting a filler as a tube shifts every fiber after it.

WTC with SWR ribbon: count rings, not tubes

WTC is where tube-based habits break down. AFL's 250 µm WTC sheet describes a gel-free outside plant cable from 48 to 1,728 fibers, built from 12-fiber SWR: a bonded ribbon that can be mass fusion spliced as a ribbon or broken out and spliced fiber by fiber.

There's no buffer tube to read a color from. Ribbons are identified by stripe ring markings printed along them, numbered 1 to 24 in AFL's chart. In that chart the marks appear to work like a tally: short rings count up, and a wider band stands in for five. Check the chart itself rather than counting from memory.

How many ring numbers you'll see depends on the fiber count:

• 48F to 288F: no binder units. Ring markings run 1 to 4 on 48F, 1 to 12 on 144F and 1 to 24 on 288F.
• 432F, 576F and 864F: 6, 8 or 12 binder units of 72 fibers each, with ring markings 1 to 6 inside each unit.
• 1,152F and 1,728F: 8 or 12 binder units of 144 fibers each, with ring markings 1 to 12 inside each unit.

On high counts, ribbon 3 exists in every binder unit, so identify the unit first, then the ring count. The sheet doesn't list the fiber order within a ribbon in text, so confirm it for your part number.

Reading an AFL cable in the field

1. Get the full AFL part number from the work order, as-builts, reel tag or sheath print.
2. Work out the family: LE Series SJ or DJ (gel-filled or Gel-Free), Hyperscale MLT, or WTC with SWR.
3. Find that part number on the family's spec sheet and read the tubes/fibers or binder unit column. Don't infer it from the fiber count alone.
4. On loose tube, count the fillers and note whether tubes hold 12 or 24. On a 24-fiber tube, check how fiber 13 is marked.
5. On WTC, identify the binder unit, then the ribbon ring count.
6. Only then identify by color. If the fibers disagree with the paperwork, believe the fibers and get the right documentation before you cut.

Six steps sounds slow. It isn't, next to a wrong ID that takes a customer down. That's why the sheet comes before the colors.

Where the app fits

Fiber Optic Color Code Lookup ships 199 cable configurations: a mix of manufacturer-specific tube layouts from 6 manufacturers, AFL included, and generic standards layouts. The color codes hub lists the AFL lines it covers as LE-Series, Hyperscale MLT and WTC with SWR ribbon. Pick the AFL build that matches the cable, then use forward lookup (fiber number to tube and color) or reverse lookup (the colors you can see to the fiber number). The interactive cross-section diagram shows the tube positions, which is the quickest way to catch a 12-versus-24 mix-up.

Two things to know before you pick. The app's LE-Series builds are AFL's Gel-Free LE-Series, a separate product with its own spec sheet, laid out at 12 fibers per tube. They are not the gel-filled SJ and DJ builds in the table above, so a gel-filled single-jacket 144F with 6 tubes of 24 has no match in the app's AFL list. Don't stand it in with the Gel-Free 144F. And on WTC at 432F and up, the app numbers ribbons straight through the cable rather than restarting inside each binder unit, so match its ribbon number against AFL's binder-unit chart. The app also names each WTC ribbon with a color, and SWR ribbons carry ring marks, not colors, so go by the ribbon number and ignore the ribbon color on these builds.

All 98,898 pre-computed lookups live in a bundled database on the phone, so the app works the same in a manhole with zero signal as it does at the truck. The app also carries 7 international color standards. It can't read a reel tag for you, though. If the build on screen doesn't match AFL's sheet for the part number in your hand, go by the sheet. The full app runs free for 24 hours with no account, then it's a single one-time $4.99 purchase, nothing recurring.

If you're newer to the base sequence, start with the 12 fiber chart, since every AFL count above repeats it. The same build-first habit applies to Prysmian fiber cable colors, where one manufacturer runs two different color orders. And for what else earns a place on your phone, see Best App for Fiber Techs.

Frequently asked questions

Related