An optical cross-connect is a passive optical device, the main purpose of which is to connect fiber optic cables (with many cores) with optical cords (with one fiber and special connectors located at the ends).

It is rational to use an optical cross-connect if it is necessary to connect active network equipment to a fiber optic network cable network. As a result, the equipment will be able to transmit an optical signal to the network.

To date construction market developed at an unprecedented level, so in the range of optical cross-connects you can find many types and modifications of these devices. The main ones include conventional optical wall connectors (KOH); cross-connects for four ports (micro CON); for eight ports (mini CON); rack-mount crosses (KOS 19”).

For high-quality installation, meeting the customer’s requirements, optical cross-connects are supplied in sets with the products necessary for operation. These include cassettes and splice-type plates, pigtails, adapters, KDZS sleeves, as well as various connecting elements.

At first glance the installation optical cross It looks like a simple procedure that does not require specific knowledge and skills. However, this statement is only partially true. The fact is that the assembly and installation of an optical cross-connect is one of the most important stages organization of distribution network. It is necessary to make a lot of effort to prevent construction from all kinds of errors.

Incorrect installation, carried out without following clear requirements and instructions, or done carelessly, can lead to a complete lack of signal in such a network. In other words, in places where cables are connected, where cable fibers are welded and where pigtails are laid, the optical signal can be attenuated so strongly that the recipient simply cannot receive such a signal. In addition, attenuation of the optical signal or broken optical fiber can occur as a result of improperly installed cable in the cross-connect. Another reason for the inability to transmit a signal in a fiber-optic cable network may be improper placement of the sleeves in the cassettes.

Thus, we can conclude that it is better to trust the installation of an optical cross-connect to a qualified specialist with considerable experience in this field.

8.1 ODF is included in the PON exchange section. ODF must have the following capabilities:

− providing free access to any of the optical ports and the ability to quickly perform cross-connection work;

− increasing the cross-connection capacity during operation;

− ensuring prompt production of installation, installation and switching of OV;

− system for laying fiber optics and patch cords, guaranteeing compliance with the requirements for the bending geometry of fiber optics;

− constructively support the installation of splitters directly in the ODF;

− occupy a minimum area.

The cross must match " Technical requirements to high-density station optical cross-connections”, approved by the Chief Technical Director of Kazakhtelecom JSC.

Basic principle of high density ODF installation modular design consists of cutting the optical station and line cables (fibers) supplied to the cross-connect onto the mounting modular tubes, through the adapter devices shown in Figure 19.

Figure 19 Figure 20

Mounting modular tubes with 12 or 16 optical fibers are fed to the splicing and switching module shown in Figure 20, where the fibers are boiled into factory-prepared picktails. Welded fiber joints reinforced with KDZS sleeves are placed in cassettes. The design of the optical cross-connect should ensure the extension of the splicing and switching module from modular blocks to a length of up to 1.5 meters due to the supply of mounting modular tubes laid in the switching and splicing module, only when installing (unbonding) optical fibers of station and linear fiber optics. SC/APC type connecting sockets are installed in special sockets of patch panels.

8.2 Due to the large number of optical distributions of various designs, including top or bottom feed of the fiber optic cable from a cable rack or through a raised floor, a detailed description of the installation is not advisable; in each specific case, the manufacturer’s instructions should be used. The length of the supply of linear cable fibers and picktails left on the cassette in the terminal device must be at least 0.5 m, and the length of the fiber supply left on the cable rack or in the raised floor is at least 2 m. Placement options are shown in Appendix 3.

NOTE For any optical cross-connect design, station cables or station patch cords must be fed to station splicing and switching modules installed in the upper part of the cabinet, in the middle part of the cabinet it is necessary to install splitter modules with input and output splitters welded into connectors (optical switching ports), and onto linear modules installed in the lower part of the cabinet, it is necessary to supply main linear fiber optic cables. There are 2 options for mounting (feeding) OLT linear terminations to the optical cross-connect:

When installing an OLT in a combined room in close proximity to the ODF and the capacity of a GPON network node for up to 2 thousand subscribers, the OLT outputs can be connected directly to the ODF trunk ports using patch cords of the appropriate length;

When installing an OLT in a containment zone and the capacity of a GPON network node exceeds 2 thousand subscribers, the connection of the OLT outputs to the ODF station ports must be carried out using 3-meter pigtails terminated on the OLT side with 48-96 station cables, and on the ODF side the station cable must be inserted and welded into station splicing and switching modules. In the latter option, switching of OLT outputs with any port of a linear trunk cable should be carried out using short patch cords inside the ODF rack between the linear and station ports of the optical cross-connect.

8.3 Inside the premises of the telephone exchange, up to the terminal cable equipment ODF should be laid OK with a non-flammable sheath. The margin for cutting the optical station cable from the station and linear parts of the cross-connect must be at least 3-3 meters.

Optical cross connectors are used to enter the optical cable and connect station equipment to the line. To implement the project construction of fiber-optic communication lines you need to select the brand and capacity of the optical cross-connect. For the end points of the designed fiber-optic line at Zhetygen station and Korgas station, required amount There are 16 sockets in the cross. At the intermediate points Kurozek station and Shelek station, where two cables are installed, 32 sockets are needed. These requirements are met by optical cross-connectors of the PR-16 type produced by JSC 2ASystem, Tula. One cross-connect is installed at the end points, two at intermediate points (sides A and B), a total of 6 optical cross-connects are required.

Since optical pigtails are ordered separately, we will choose standard pigtails 1 m long. with FS type connectors (accordingly, the optical cross-connector will also be equipped with FS type connectors).

Optical cross (Fiber Cross) Distribution panel PR 16

General information.

Optical cross (Fiber Cross) distribution panel PR 16 provides:

• - Input, placement, fastening and storage of stock of station and line cables;
• - End seal, connection, switching of line and station cables with optical fibers in a public communication network, in technological communication networks and special-purpose communication networks;
• - Connection of control and measuring equipment;
• - Possibility of marking linear and station circuits.

Technical characteristics of the optical crossover.

The maximum number of incoming linear fiber optic cables is 4 pcs.

The maximum number of optical connecting sockets on the panel is 16 pcs.

Overall dimensions of the Optical cross (Fiber Cross) PR 16 - 484 x 280 x 44mm

The weight of the Fiber Cross distribution panel PR 16 is 2.4 kg.

Type of optical ports - FC, SC, ST, FC/APC, SC/APC

Optical crossover delivery set.

Optical cross (Fiber Cross) distribution panel PR 16 is equipped according to table 3.3

Table 3.3 - Optical crossover delivery set

	Name	Quantity, pcs.
	Distribution panel
	Splice plate
	Screw-washer-nut set	1 (supplied by agreement)
	Screed 80mm
	Screed 140mm
	Organizer platforms
		By number of ports
	Passport products

Notes

It is allowed to replace the products included in the delivery set with similar others that do not impair the presentation, performance characteristics and comply with safety requirements.

Delivered as agreed with the customer

Optical crossover safety requirements.

Before starting work, carefully study this passport.

The optical cross-connect must be used in accordance with the purpose specified in the passport.

Optical cross device (Fiber Cross) PR 16.

The optical cross is metal box, painted using powder coating technology, which ensures reliable protection from external influences. Inside the optical cross there is a splice cassette (splice plate) for laying sleeves and a supply of fibers (it is possible to place 24 fibers on one splice cassette)

The optical cross-connect has four holes for optical cable input/output. The holes are closed with rubber plugs for protection. internal space optical cross from dust; when installing an optical cable (OK) in PR 16, you can select one of four holes for OK input (or use all four if necessary).

Installation instructions for optical cross (Fiber Cross) PR 16

Removing the packaging - be careful not to damage the optical cross-connect with the tool. After opening the package, check external condition assembly units and parts of the optical crossover, as well as the availability of all accessories according to the packing list.

Preparation for installation

Before you begin installing the OK, make sure that the mounting brackets on the right and left sides of the optical cross-connect are firmly secured;

Place the Fiber Cross PR 16 on the desktop for mounting OK.

Figure 3.10 - General form distribution panel Fiber Cross PR 16 (pictured without top cover with FC connectors).

Cable cutting and entry

Cut the cable in accordance with Figure 6.14.

Insert the cable into the Fiber Cross PR 16 through the hole, cutting the rubber membrane.

Secure the OK using the ties included in the kit. Secure the central power element using a bracket and screws as shown in Figure 3.12.

Place heat shrink sleeves onto the pigtails.

Figure 3.12 - Optical cable input

Works with optical fiber.

Strip fibers and weld in accordance with the recommendations for the welding equipment used;

Number the modules of the cable being installed;

Number the pigtails and weld them with the corresponding fibers;

Bake heat-shrinkable sleeves (heat-shrinkable sleeves are included);

Place the sleeves and fiber stocks in the cassette according to Figure 3.14, 3.15. (drawings of cable module insertion and pigtail placement are spaced for ease of reading).

When laying stocks of cable fibers, sleeves and pigtails, ensure that the bending radius of the fibers and pigtails does not exceed 30 mm

Close the splice cassette with a transparent lid.

Connect the pigtails to the adapters according to their numbers.

Figure 3.13 - Input of cable modules

Figure 3.14 - Layout of pigtails

Rack mounting.

The optical cross (Fiber Cross) distribution panel PR 16 is secured in a 19-inch rack with four M 6 screws (fastening screws are not included in the delivery package). Place and secure the cable supply in convenient location.

To assess the quality of installation of the optical cross-connect, reflectograms of each OF in the regeneration section are taken. If optical attenuation is normal and there are no defects in the welded joints, the station equipment is connected to the line using patch cords.

Table 3.4 - Organization of jumpers on the optical cross-connect of the Kurozek station access node

At all communication points on optical cross-connections, 1-4 optical fibers are switched to Huawei OptiX OSN 1500B equipment. A linear path is organized along 1-2 OBs for the operation of a digital transmission system; 3-4 OBs are also connected to digital equipment and are used for automatic reservation of the linear path.

An optical cross-connector is a device specially designed for detachable, convenient connection of optical cords and multi-fiber cables, which is carried out using sockets.

There are two types of crosses:

• wall crosses - mounted on walls. Available with 16...72 ports, designs with a large number ports (multiples of 16). This type of crosses has both lower and top position cable entries;
• rack cross-counters - installed directly in cabinets. They are a metal box, the back of which is equipped with cable entries, and the front has sockets specially designed for optical sockets. Series of rack crosses differ from the nominal number of floors, which is measured in units.

The design of the optical crossover is a metal box that can be disassembled. The front surface will contain places where you can attach sockets (optical adapters). Inside the cross itself there is a place where you should attach optical cassettes with special grooves designed for fixing sleeve kits to protect the joints. When installing an optical cross-connect, the sleeves must reliably protect the welding points.

The design of the optical cross itself allows you to place excess length in the box fiber optic cable. This ensures the required bending radius, which corresponds to certain technical specifications on the use of this type of cable. The rear part of the structure is equipped with elements for rigidly attaching the optical cable to the cross-connect. There are also required holes for fastening inside the optical fiber cross-connect.

Rack crosses: design features

A common type of optical products for communication is optical rack-mount cross-connects (abbreviation KRS). These designs are used to modularly fill server racks and are not used as separate switching units.

This type of crossover is a durable metal box with connectors and special inputs designed for optical cables. The cross can accommodate from 2 to 8 cables, switching can occur from 8 to 48 ports.

Rack crosses have standard universal sizes, manufacturers create convenient modern fastenings and thoughtful equipment for them.

Design features also include:

• the ability to place from 8 to 144 different adapters and connect any type of cable;
• durable steel body, which is necessarily covered with a layer of protective paint;
• compliance by manufacturers with relevant quality standards for such equipment under strict control, which reduces the presence of defects in such structures to a minimum;
• Rack-mount crosses can be installed inside closed cabinet and inside the rack.

KRS cross-countries may differ in the number of adapters, design features, and the number of connectors.

There are simple block crosses with universal standard height(unit U), a multiple of 44.45 mm, as well as crosses with retractable panels and side fastenings that are convenient when carrying out installation work. The height of the products is determined simply, since the width of the design contains eight adapters, while the number of ports in the cross-connect can vary from 8 to 144.

It is important! The depth of the crossover is not technically regulated, which allows manufacturers to offer their own options.

Optical connectors are used only in indoors, however, for some operating conditions, the use of waterproof and dustproof housings is recommended.

Installation of the fiber optic system is carried out by specialists who must strictly follow the list of rules and safety standards.

When carrying out installation work, you should take into account following features and settings:

• it is necessary to leave gaps between the housings during installation rack crosses. This is done for convenience during future maintenance;
• if the cable does not have connections, then switching inside the optical cross-connect is carried out using pigtails;
• if it is necessary to change panels, it is possible to choose an option with suitable adapters; the panel is changed using special latches.

About the demand for optical cross connects

On this moment Consumers give preference to convenience when installing cross-connects, which is why sales of rack-mounted retractable cross-connects, which are equipped with shelves for cable spare parts, are increasing. It is also convenient to work with pre-assembled cross-connects for welding; this simplifies the task of installing fiber optic equipment at the assembly site.

Cable television services give preference to reliable, vandal-proof designs with locks that will protect equipment from burglary and damage. Dust- and moisture-proof crosses are relevant when used in industrial automatic systems.

Universal designs began to appear that can be used in both rack and wall-mounted versions. There are also ultra-small cross-connects that are used for mounting small LANs, as well as cross-connects with high-density panels.

Features of choosing optical connectors:

• An inexpensive cross is difficult to maintain in the future. Difficulties may arise during the assembly process if the customer wants to replace, for example, the lower pigtails. Therefore, it is better to buy high-quality optical connectors for certain parameters;
• the product must be certified, have the appropriate licenses, best of all, international standard. Foreign partners and well-known Russian manufacturing companies strictly comply with warranty obligations in the event of failure of optical cross-connects;
• most best option- ordering pre-assembled cross-connections, this saves time and allows you to achieve appropriate quality during installation;
• The documentation for the cross must be complete. The passport of the optical crossover must contain not only data on technical and operational characteristics, but also complete legal address manufacturer, license and certificate numbers, stamps of the relevant control services.

Working with fiber optic equipment requires highly qualified specialists and expensive equipment. Contact companies that actually install optical crossbars on professional level and have extensive experience in this type of work.

Good afternoon, optical cross-connects BON produced by STC "PIK" look like this:

BON equipment:

Approximate configuration of BON in the figure:

Rules for installing and assembling BON:

1 After opening the package, check the external condition of the assembly units and parts of the optical box, as well as the presence of all accessories according to the delivery package.

2 Secure the box to the wall using screws or anchor bolts from the delivery kit, having previously made markings along the holes on back wall BON.

3 Option for preparing the main cable for entry into the BON.

3.1 Wipe the outer shell of the optical cable with a rag over a length of 2.0 m. Cut the cable in accordance with Figure 1a.

3.2 At a distance of 1500 mm from the end, make a circular shape on the cable sheath incision Using a special tool along the entire marked length of the cable endmake a longitudinal cut and remove the shell. Remove the armor from the cable, leaving 30 mm.

3.3 Take a PRPPM 1×2 wire 250-300 mm long, free it from the insulation at the end at a length of 60-70 mm, tin it and apply a bandage to the stripped and tinned section of the steel cable sheath (armor). Then solder the bandage with POSS 30-2 solder. On top of the wire bandage, over the entire section of the steel shell, wrap two layers of insulating tape with a 50% overlap.

3.4 Make circular and longitudinal cuts on the inner sheath of the cable. Make a longitudinal incision with a special tool. Next, remove the inner sheath from the cable core.

3.5 Wipe the modules and CSE with liquid to remove hydrophobic filling and dry rags.

3.6 If the optical cable has an armored cover made of galvanized steel wires, cut in the following sequence in accordance with Figure 1b:

• Using a mechanic's knife, make a circular cut in the outer sheath of the optical cable at a distance of 1.5 m from the end of the optical cable, then make a longitudinal cut in the sheath of the optical cable from the end of the optical cable to the circular cut;
• remove the outer sheath of the optical cable;
• untwist the twisted steel wires;
• cut off the excess length of the wires with side cutters or cable cutters;
• then carry out actions in accordance with clauses 4.3-4.3.5.

3.7 If there are water-blocking tapes and threads in the OK design, remove them flush with the edge of the inner shell. Remove hydrophobic filler,using a rag and D-Gel.

3.8 If the OK design contains synthetic (aramid) threads, cut them at a distance of 150 mm from the edge of the outer shell (see Figure 1a) with scissors for cutting synthetic threads, and fasten the ends of the threads with insulating tape.

3.9 Remove the cord fillers of the OK core (if any) using side pliers.

You may also be interested in: “How to choose the capacity of a linear cross-connect when building a GPON network?”

4 Installation of BON cable.

4.1 Insert the end of the prepared optical cable through the special holes in the BON, cut the central power element to the required length, remove the plastic sheath (if any) and secure it with a strip with two screws. If the optical cable has aramid threads, secure them together with the central power element, remove excess length. To enter the cable into the BON-72S, make a cross-shaped cut in the rubber plug with a knife. In BON-72SP, at the cable entry point, install a pipe of the required diameter from the delivery kit (the pipe must go outside, and in the transport position the pipes are installed inside the cabinet).

4.2 Secure the fiber optic cable sheath with cable ties to the box body at the cable entry point. In BON-72S, a metal clamp is also provided for fastening the input cable. Ground the optical cable by connecting the shielding wire to the grounding pin on the wall of the box.

4.3 Lay out the optical cable modules inside the BON. Determine the required length to the point of fixation in the cassette, remove the excess length of the optical module. Wipe optical modules and each optical fiber with isopropyl alcohol (2-propanol) and lint-free wipes.

4.4 Mark the modules with self-adhesive markers. The marking of the modules must correspond to the marking of the fibers of the optical boreholes.

4.5 Collect the inserted optical modules into a bundle and secure the bundle with cable ties at the entrance to the splice cassette. Work should begin from the bottom splice cassette.

4.6 Prepare the fiber to be mounted for welding in accordance with the instructions included with the welding machine. To remove the protective shell optical fiber use a stripper. Place KDZS sleeves on the ends of the OB.

4.7 Using an optical fiber splicing machine, connect the optical mounting cords (pigtails and fibers of the mounted cable. When working, follow the operating instructions for the splicing machine.

4.8 Verify the integrity of the welded joint using a reflectometer.

4.9 Protect the welded joint using a KDZS sleeve. It is prohibited to use a KDZS sleeve to protect more than one welded joint of an optical fiber!!!

4.10 After the sleeves have cooled, install the welded joint in seat splice cassette holder. Place stocks of spliced ​​optical fibers inside the splice cassette.

4.11 Place modules and pigtails inside the BON. Make sure there is no tension on the fibers. Enter the necessary data in the plate to indicate the fiber crossing addresses on the cover of the splice cassette.

Safety requirements:

When performing installation and installation work, you should be guided by the requirements of the “Rules on labor protection when working on linear structures cable lines transmission" POT RO-45-009-2003.

When cutting optical cable and its waste, special containers should be used. It is not allowed for pieces of optical fiber to come into contact with the assembly table, the floor, or the clothes of installers, as this can lead to injury to unprotected areas of the skin during work and when cleaning the workplace.

To avoid damage to vision, visual or optical inspection of the end of the optical connector through which the optical signal is transmitted is prohibited.

When working with optical connectors, precautions should be taken to prevent deformation and avoid bending the cable with a radius less than that allowed by the cable specifications. The static bending radius of cords during installation and operation must be at least 40 mm, for multicore optical cables - at least 20 cable diameters.

To prevent injury, installers must be provided with by individual means protection (safety glasses according to GOST 12.4.013-85 and special clothing).