Optical Distribution Frame Tutorial

Optical Distribution Frame (ODF) is integrated components in any fiber management system to handle termination and cross-connection of cables. This tutorial will give a detailed introduction to ODF.

What Is Optical Distribution Frame?

Optical Distribution Frame (ODF) is used for wiring connections between fiber optic cables and optical communication devices or among the communication devices. It is an important corollary equipment in optical transmission system, mainly used for fiber optic terminal splicing, fiber optic connector installation, optical path adjusting, excess pigtail storage and fiber optic cable protection, etc.

ODF has an important role for the safe operation and flexible use of fiber optic communications networks. With the increasingly high degree of network integration, there has been optical digital mixed distribution frames which integrate ODF, DDF, and power distribution unit in one set. They are used for wiring systems in fiber to the cell, fiber to the building, the remote module office and small wireless base station.

In the past optical communication construction, fiber optic cable is usually several to tens of cores, and the capacity of ODF is generally below one hundred, which shows too small capacity of pigtail storage, inconvenience of connection maneuver, less functional, simple structure and other shortcomings.

Nowadays optical communication has been widely used in the long haul and local network relay transmission. Optical fiber has become the direction of the access network. The new fiber optic network constructions that in most places are all choosing to use cable that has a large number of cores as far as possible, which puts forward higher requirements for the capacity, function and structure of optical distribution frames.

Structure of ODF

1. The rack structure
1) Frame structure enclosed, semi-enclosed and open.
2) Rack height divided 2600mm, 2200mm and 2000mm categories. Its width is recommended to choose an integer multiple of 120mm, depth recommended use 300mm, 450mm and 600mm.
3) Rack dimensions of the deviation does not exceed ± 2mm; outer face of the bottom plane of the vertical tolerance is not greater than 3mm.

2. The mechanical moving parts
Mechanical moving parts should be flexible rotation, plug moderate locked reliable, construction, installation and maintenance. Door opening angle should not be less than 110 °, the gap is less than 3mm.

3. The introduction of fiber optic cable bend radius
Introduction of fiber optic cable into the rack, the bending radius should not be less than 15 times the cable diameter.

4. The frame structure
Structure should be strong, the assembly should have the consistency and interchangeability, no loose fasteners. And operating parts exposed sharp edges should be rounded.

5. The protective cover, liner and core and pigtail bend radius
Fiber optic cable through the metal plate hole and turn sharp edges along the structure, you should install protective cover and liner. Core, pigtail is where both bending radius of curvature shall not be less than 30mm.

6. The surface of the rack
Coating layer should be smooth surface, uniform color, no sagging, no exposed at the end; rusted metal parts without burrs.

7. The structure of the device of the text, graphics, symbols and signs
Structure on the device text, graphics, symbols and signs should be clear, complete, and correct.

Materials of ODF

1. Anti-corrosion
ODF all parts used material should have antiseptic properties, such as corrosion resistance of the material should not be treated with preservatives; their physical and chemical properties must be stable, and with the pigtail cable jacket and sheath compatibility. To prevent corrosion and other damage, these materials must also be used with other devices that are compatible with the materials.

2. Rust-proof
ODF in the surface plating of metal structure, through the salt spray test methods for 48h salt spray test, appearance without visible rust.

3. Coating processing requirements
Coating process using a metal structure, the coating and the substrate should have good adhesion, adhesion should not be less than GB/T9286 standard Table I two requirements: at the intersection of the incision and or along the cut edge coating layer off the affected cross-cut area significantly greater than 5%, but not significantly more than 15%.

4. Combustion performance requirements
Equipment in non-metallic materials for structural parts and fiber optic connectors combustion performance should meet the following conditions:
1) The test sample is not the ignition;
2) The test sample from the fire continued to burn for longer than flame 10s, and the flames or falling from a test sample flaming or glowing particles were not placed in the combustion spreads to the bottom of the test sample below.

Functions of ODF

1. The cable fixing and protection features
Should have a cable entry, fixing and protection devices. The device will introduce cable and fixed to the rack, and cables in the cable core to protect from damage. Metal parts and metal rack cable insulation, immobilized metal sheaths and strengthen the core fiber optic cable should be connected to high voltage protective earthing device reliability.

2. Optical fiber termination function
Should have a fiber optic termination device. The device is easy to operate cable core and pigtail connection, construction, installation and maintenance. And protect the joints can be fixed straight without displacement, to avoid external influences, to ensure core coiled cable, pigtail from damage.

3. Adjusting line function
Through the optical fiber jumper connector plug can be quickly and easily dispatch the core fiber optical transmission system serial number and change the way sequence.

4. Core and pigtail cable protection
After the core cable stripping protective devices have a fixed termination after the introduction of fiber-optic devices.

5. The capacity
Capacity and capacity per rack unit (determined by the number of adapters) product standards should make provision terminating fiber optic devices, optical storage devices, fiber optic distribution device connected to the range at full capacity should be able to complete configuration.

6. Marking record
Rack and the unit should have a complete identification and recording device for easy identification of the core sequence number or the transmission path, and the recording device should be easy to modify and replace.

7. Optical storage capabilities
Rack and the unit should have sufficient space for the remaining fibers.

Classifications of ODF

1. Unit Type
Modular optical distribution frame is installed in a rack multiple units, each unit is a separate fiber optic patch panels. This patch only to retain the original features of small fiber optic patch panels, but also through structural deformation rack provides space utilization, high-capacity optical distribution frame is an early common structure. However, because of its inherent limitations on the space available, on the operation and use of some inconvenience.

2. Drawer Type
The drawer-type optical distribution frame is divided into a plurality of rack units, and each unit consists of one or two drawers. When performing welding and transfer line, pulled out a drawer in the rack outside the corresponding operation, which has a larger operating space, so that each unit independently of each other. Pull and push the drawer in the state are equipped with locking device, can be used to ensure stable operation, accurate and unit connecting devices safe and reliable. This fiber distribution frame while the fiber optic terminal operator cleverly to provide a larger space, but as the cell type, the optical cable storage and cloth placed, they can not provide maximum convenience. This rack is a form up.

3. Modular Type
The modular structure of optical distribution frame is divided into a variety of functional modules, fiber optic cable splicing, deployment cable storage and other functions operating. Respectively, at the completion of each module, these modules can be combined as desired rack mounted to a common inside. This structure provides maximum flexibility to better meet the needs of communication networks. Current release of modular high-capacity optical distribution frame, the use of panels and drawers, and other unique structure, the deployment of optical fiber splicing and line operation more convenient; addition, the use of vertical groove and intermediate distribution frames, effectively solve the pigtail laying and storage problems. So it is a large-capacity optical distribution frame of the most popular, but it is currently relatively high cost. Luckily, Fiber-MART can offer the most cost-effective large-capacity ODFs from 12 fibers to 144 fibers with rack mount, even lager such as 144 fibers, 216 fibers, 288 fibers, 360 fibers, 432 fibers, 504 fibers, and 576 fibers with floor mount are all available.

Optical distribution frame selection is an important and complex task, should be based around the local circumstances, take into account all factors, in earnest to understand, on the basis of repeated comparisons to choose the one that best meet the current needs and future development of optical distribution frames.