SPL Splicing SPL-04 Step 4 of 13
Mid-Span Access and Expressing Tubes
Open a cable at mid-span and reach only the fibers you need, without disturbing the express fibers that stay in service.
Crew
- Lead Splicer
- Splicer Helper
Hazards
- Cutting a Live Express Fiber
- Induced or Fault Voltage on Cut Armor
- Cuts from Sheath Tools
- Glass Fiber Shards
Purpose
Reach only the fibers you need in a cable that passes through the closure, without disturbing the express fibers that stay whole. Express fibers may already carry live customers. One wrong cut can take down a feeder.
When to Do It
- When a cable passes through the closure and the matrix calls for splicing only some of its fibers.
- After the closure is staged and the SPL-03 preparation for any butt-spliced cables is done.
- Previous step: SPL-03 Closure and Cable Preparation. Next step: SPL-05 Fiber Identification and Routing.
Roles
- Lead splicer: makes the window cut, opens the assigned tubes and cuts only the assigned fibers.
- Splicer helper: supports the express loop, reads the matrix aloud and confirms each fiber id before a cut.
Equipment and Materials
- Mid-sheath window cutter or sheath slitting tool.
- Mid-span access tool sized for the buffer tubes.
- Closure express basket and the closure’s tube ties.
- Visual fault locator (VFL), for fiber checks where the owner allows.
- The current splice matrix.
Safety
Procedure
- Make the mid-sheath window cut per the closure instructions.
- Use the window length the closure model requires: per manufacturer instructions.
- Set the tool depth so it opens the jacket without touching the tubes.
- Secure the strength members at both ends of the window in the closure’s clamps.
- On armored cable, bond the armor on both sides of the window to the closure bond bar, so armor continuity and grounding are kept (owner bonding standard; NESC).
- Route the uncut express tubes through the express basket.
- Lay them in a loose loop that keeps the bend radius: per manufacturer instructions.
- Do not twist or pinch the tubes under the basket cover, so express fibers do not pick up bend loss.
- Open only the tubes being accessed.
- Identify each tube by color with the TIA-598 sequence and check it against the matrix.
- Open the tube with a mid-span access tool, not a knife, so the fibers inside are not scored.
- Identify the fibers assigned to splice.
- Read each fiber color and count against the matrix.
- Have the helper read the matrix aloud while you point to each fiber.
- Cut only the fibers assigned to splice in the matrix.
- Never cut an express fiber.
- Leave the cut fibers long enough to reach their tray.
- Route the cut fibers to their trays and leave the express fibers in their tube or loop.
Hold Points
Records to Keep
- Photo of the express basket with the express loop in place.
- Photo of the armor bonds on both sides of the window, on armored cable.
- Matrix marked with the fibers cut and the fibers expressed.
- Name of the owner contact if live traffic was coordinated.
Common Mistakes
- Cutting a live express fiber. This is the costliest splicing mistake. Verify every fiber against the matrix before you cut.
- Kinked express tubes. A tight loop adds loss on fibers that already work. Keep a loose loop within bend radius.
- Unbonded armor at the window. Cutting the window splits the armor in two. Bond both sides to the closure bond bar, or one side floats.
- Overfilled baskets. Tubes crushed under the basket cover pick up macrobends. Use the closure’s capacity limits.
Standards and References
-
Telcordia GR-771 -
ANSI/TIA-598 NESC (IEEE C2)for bonding and grounding.- Owner bonding and grounding standard.
- Closure manufacturer’s instructions for mid-span entry and express storage.
- Owner network operations procedures for working near live service.
On the Map
- Closure Interior: the express basket where uncut tubes loop through the closure.
- Buffer Tubes and Color Code: the tubes you identify by color before opening any of them.
Related Tools
- Fiber Color Locator: confirm which tube and fiber colors match the fiber numbers in the matrix.
SPL-04 · Field Checklist
Checklist
0/8items ticked
Tick each procedure step and hold point as the crew completes it. Ticks stay on this device only. They are a personal aid, not a hold-point release or a project record; follow the owner’s sign-off process.
OSP Map · Handhole Detail
On the Map
- Closure InteriorExpress basket, splice trays, strength-member clamps, grounding and seals inside a closure.
- Buffer Tubes and Color CodeColor-coded tubes and fibers identified with the TIA-598 sequence.