• Horizontal
  • Horizontal
  • Horizontal
  • TWFOSCHK Fiber Optic Splice Closure

  • Model:TWFOSCDK
  • Application: Aerial,Mounting,Direct buried
  • Sealing: Mechanical or shrinkable
  • Brand Name:Teleweaver

1. Scope of application

This Installation Manual is suit for the Fiber Optic Splice Closure (Hereafter abbreviated as FOSC), as the guidance of proper installation.

The scope of application is: aerial, underground, wall-mounting, duct-mounting, handhole-mounting. The ambient temperature ranges from -40to +65.

2. Basic structure and configuration

2.1 Dimension and capacity

Outside dimension (LxWxH)

470x180x125 (mm)

Weight (excluding outside box)


Number of inlet/outlet ports

3 (pieces) on each side (total 6 pieces)

Diameter of fiber cable

Φ8—Φ20 (mm)

Capacity of FOSC

Bunchy: 12—96 (Cores)

Ribbon: max. 144(Cores)

2.2 Main components


Name of components






1 set

Protecting fiber cable splices in whole

Internal diameter:



Fiber optic splice tray


max. 6 pcs (bunchy)

max. 4pcs  (ribbon)

Fixing heat shrinkable protective sleeve and holding fibers

Suitable for:

Bunchy:12,24(cores) Ribbon:3 (pieces)



1 set

Fixing reinforced core of fiber- cable and FOST


Seal fitting

1 set

Sealing between FOSC cover and FOSC bottom


Port plug

6 pieces

Sealing empty ports



testing valve

1 set

After injecting air, it is used for pressure testing and sealing testing

Configuration as per requirement


Earthing deriving device

1 set

Deriving metallic components of fiber cable in FOSC for earthing connection

Configuration as per requirement

2.3 Main accessories and special tools


Name of accessories





Heat shrinkable protective sleeve

Protecting fiber splices

Configuration as per capacity


Nylon tie

Fixing fiber with protective coat

Configuration as per capacity


Insulation tape

1 roll

Enlarging diameter of fiber  cable for easy fixing


Seal tape

1 roll

Enlarging diameter of fiber  cable which fits in with seal fitting

Configuration as per specification


Hanging hook

1 set

For aerial use


Earthing wire

1 piece

Putting through between earthing devices


Abrasive cloth

1 piece

Scratching fiber cable


Labeling paper

1 piece

Labeling fiber


Special wrench

3 pieces

Fixing bolts, tightening nut of reinforced core


Measuring paper

1 piece

To measure circle, of which its diameter is enlarged with seal tape


Buffer tube

to be decided by customers

Hitched to fibers and fixed with FOST, managing buffer

Configuration as per requirement



1 bag

Put into FOSC before sealing for desiccating air.

3.  Necessary tools for installation

3.1 Supplementary materials (to be provided by operator)

Name of materials


Scotch tape

Labeling, temporarily fixing

Ethyl alcohol




3.2 Special tools (to be provided by operator)

Name of tools


Fiber cutter

Cutting off fibers

Fiber stripper

Strip off protective coat of fiber cable

Combo tools

Assembling FOSC

3.3 Universal tools (to be provided by operator)

Name of tools

Usage and specification

Band tape

Measuring fiber cable

Pipe cutter

Cutting fiber cable

Electrical cutter

Take off protective coat of fiber cable

Combination pliers

Cutting off reinforced core


Crossing/Paralleling screwdriver


Waterproof cover

Waterproof, dustproof

Metal wrench

Tightening nut of reinforced core

3.4  Splicing and testing instruments (to be provided by operator)

Name of instruments

Usage and specification

Fusion Splicing Machine

Fiber splicing


Splicing testing

Provisional splicing tools

Provisional testing

Notice: The above-mentioned tools and testing instruments should be provided by the operators themselves.

5. The process of installing FOSC

Step One - Open the closure

Cleaning the locale and determine where to install the FOSC and then place

fiber cables required.

Check whether the main components and accessories have been well prepared

inside the package.

Open the closure

Unscrew fixing bolts and open the closure by lifting the unscrewed bolts with no need completely unbolting to avoid loosing.

See Drawing 1

Important issues: If the weather condition is not good enough, then a tent must be pitched

for waterproof and dustproof.

5.2 Step Two -Determine length of fiber cable to be fixed and stripped inside FOSC

5.2.1 . Fiber cable in 55mm length: the distance from seal fitting to fiber cable pressboard

. Fiber cable in 2020mm length: it is used to be winded and spliced after stripping.

. Fiber with protective coat in 420mm length: the distance from the fixing

point of fiber cable to the fixing point of FOST (fiber optic splice tray).

. Fiber in 1600mm length: after stripping off the protective coat, it is to be winded

inside the FOST after splicing with other fibers

5.2.2   See Drawing 2

Important issues:  1. Reserve enough length of fiber cable to be spliced.

2. Stripping length also could be decided by customers according to

installation requirement

5.3  Step Three – Strip off fiber protective coat of fiber cable and fiber

5.3.1  Strip off protective coat of fiber cable from the temp. locating mark with the cutter and the

stripper, please refer to Drawing 2 for stripping length. Stripping length also could be

decided according to installation requirement

5.3.2  See Drawing 3.

Important issues:  If it is difficult to pull all the protective coat of fiber cable at one time, strip

it off section by section to avoid fiber breakage.

5.4 Step Four – Separate fiber cores and prepare work prior to fixing fiber.

5.4.1 Wind 2 layers of insulation tape on protective coat of fiber core. Meanwhile, get rid of

the stuffing to separate fiber core and clean them. Form a ring with the diameter

of 100mm or so and fix it on the fiber temporarily by adhesive tape.

5.4.2  This FOSC is provided with six inlet/outlet ports. Number of fiber cables is determined

by the customers according to their actual requirements and the corresponding number

of port plugs should be taken out. The max number of fiber cables to be installed is six.

5.4.3  This FOSC is suitable for the following diameters of fiber cables respectively:

Port A: suitable for fiber cable with max. external diameter ф20mm

Port B: suitable for fiber cable with max. external diameter ф16mm

Port C: suitable for fiber cable with max. external diameter ф13mm

5.4.4 The corresponding inlet/outlet ports are to be selected according to fiber cables

actually installed. When the diameter of fiber cable is smaller than that of the

inlet/outlet port, then the sealing tape should be used to enlarge the external diameter of

fiber cable, of which the perimeter could be measured by measuring paper marked by Hole A, Hole B, Hole C, coming as accessories.

5.4.5  Reserve reinforced core in 40mm length and cut off the unnecessary ones.

5.4.6  See Drawing 4

Important Issues: 1. Before the seal tape is used for enlarging the fiber cable diameter, it shouldbe scratched and to be cleaned with abrasive cloth and ethyl alcohol.

2. Cut off reinforced core with a special cutting plier.

5.5  Step Five - Fix reinforced core and fiber cable

5.5.1   Upon finishing the above steps, then demount port plugs, pressboard and fixing nut of

reinforced core.

5.5.2 Tighten fiber cable pressboard. If the diameter of fiber cable is not long enough, then

enlarge it with insulation tape.

5.5.3 Tighten nut of reinforced core with the special wrench (plastic) and then retighten it with

the metal wrench.(the metal wrench should be provided by operator).

5.5.4   See Drawing 5

Important issue: Make sure to check whether the fiber cable stripped fits in with the fixing ports

or not. If not, the adjustment should be done in time. Otherwise it will affect

installation quality.

5.6  Step Six - Splice fibers

5.6.1     Follow user manual of fusion splicing machine to splice fiber cores.

Important issue: pay attention to the twist and bend of fiber.

5.7 Step Seven -Install heat shrinkable protective sleeve and house fibers

5.7.1  When having completed splicing the fibers, the first fiber ring should be housed

on the farthest side of FOST, the remaining fiber should be winded, forming a ring

with diameter not less than 80mm. then put it into FOST (Fiber Optic Splice Tray)

together with heat shrinkable sleeve for splice protection.

( Firstly fix heat shrinkable protective sleeve into the slot, then enlarge the diameter of

fiber ring properly.)

5.7.2  see Drawing 6

Important issue: pay attention to the twist and bend of fiber.

5.8  Step Eight - Check up comprehensively

To ensure the technical requirements, the following instructions must be followed:

5.8.1 The fibers in the FOST are spliced and installed orderly. The curved diameter

of fiber meets with the technical requirements.

5.8.2 The internal tighteners are tightened.

5.8.3 The inlet/outlet ports without fiber cables must be blocked up with the port plugs.

5.8.4 Control the amount of seal tape within a proper range.

5.8.5 Seal fitting is installed neatly and smoothly.

5.8.6 Seal the cover of seal fitting

5.8.7 See Drawing 7

5.9  Step Nine – Assemble FOSC housing

5.9.1  Put the FOSC cover on the FOSC bottom directly.

5.9.2  Put two pieces of insert plates into the slot.

5.9.3  Insert two pieces of locating bolt of FOSC and tighten it with the special wrench.

5.9.4 If the FOSC is for aerial application, then put the hanging hook on one side of the closure

and then tighten fixing bolts on both sides. Otherwise tighten the four fixing bolts on

four corners respectively.

5.9.5  See drawing 8

Important issues: cleaning the housing and pay attention to the above sequence.

6. Fiber Optic Splice Closures (FOSC) inspecting and testing items

Inspecting  item

Technical Requirements

Inspecting type

Routine test (Before leaving factory)

Type test


Each small package contains one fiber optic splice closure, together with its accessories, tools, installation manual and packing list.


At least 3 sets sampled each time


Intact in shape, no burrs, bubbles, chaps, pores, warps, impurities and other defects, all background colors should be even and continual.

Dimension and capacity

Outside dimension (LxWxH)

470x180x125 (mm)

Weight (excluding outside box)


Number of inlet/outlet ports

3 (pieces) on each side (total 6 pieces)

Diameter of fiber cable

Φ8—Φ20 (mm)

Capacity of FOSC

Bunchy: 12—96 (Cores)

Ribbon: max. 144(Cores)

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