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Sigree Presentation

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Sep 19th 2012

THE PRESENTATIONIntroduction This presentation has 2 parts Part 1 :is about giving a broad idea about the concepts of Optical Fiber and OF Cables, (OPGW, Lashed cables, ADSS, Under Ground & Duct Cables ) without going into the deep technicalities. Part 2 :is about fiber communication in Electrical Utilities and its applications.

Sep 19th 2012

Part 1

1.1 Fiber Optic Technology

Sep 19th 2012

WHAT ARE OPTICAL FIBERS ?Optical Fibers are thins long (km) strands of ultra pure glass (silica) or plastic that can to transmit light from one end to another without much attenuation or loss.

Fiber Construction

Fiber cables consists of 3 parts 1-Core: it is where the light propagates and have the biggest refractive index. 2-Clad:part of the light wave propagate and have lower refractive index value 3-Caut:the output coverSep 19th 2012

Light Propagation Light propagates due to total internal reflection Light > critical angle will be confined to the core Light < critical angle will be lost in the cladding

Fiber TypesCladding Core

LED Laser Muliti Mode

Cross section

Cladding Core

Laser Single Mode

Multi-Mode 50/62.5um core, 125um clad Atten-dB/km: 3dB @ 850nm

Single-Mode 9um core, 125um cladding Atten-dB/km: 0.4/0.3dB 1310nm/1550nm

Fiber Types

2006, VDV Works LLC

Factors that affect the Light wave through propagation

1. Refractive index n for core and clade. 2. Fiber attenuation 3. Dispersion

Sep 19th 2012

Fiber Attenuation ( reduces the power of the signal)The two main loss mechanisms in fiber is absorption and scattering, 1-Light absorption: As light passes through fiber it is absorbed and converted into heat, due to molecular resonance, for example hydrogen and hydroxide resonance occurs at 1244 nm and 1383 nm. 2-Rayleigh scattering: Scattering causes the dispersion of light energy in all directions, and one of the directions is the backward direction in this case the scattering is called "backscattering". Forward light scattering (Raman scattering) and backward light scattering (Brillouin scattering) are two additional types of scattering those can occur under high power conditions.Sep 19th 2012

Attenuation Vs. WavelengthAttenuation depends on fiber type and wavelength of the transmitted signal

Dispersion (reduces the effective bandwidth available for transmission )There are three types of dispersion:1- Modal Dispersion (MD) for multimode fiber. Modal Dispersion typically occurs in multimode fiber, due to its large core diameter, for example 62.5 um, it carries many modes those travel through different paths thus a short pulse that consists of many modes will spread because each mode will reach the destination in a different time.

Sep 19th 2012

Dispersion2- Chromatic Dispersion (CD). Chromatic Dispersion is about the difference in speed between the various wavelengths contained in a light pulse, each light pulse consists of many wavelengths, each wavelength travels on its own speed down the fiber, thus it reaches the destination in a different time than other wavelengths, which results in the pulse broadening phenomena, please see the below figure:

Sep 19th 2012

Dispersion3- Polarization Mode Dispersion (PMD).(significant for speeds more than 10Gb/s for single mode fiber. Different polarizations travels through different paths thus different lengths down the fiber which leads to different arrival time at the destination, this difference in speed comes from the fact that a fiber core is perfectly a circle all the fiber length, also mechanical stresses twisting, bending, and temperature variations all cause PMD to change, that`s why its not a fixed value like the CD.

Sep 19th 2012

Fiber Optic Link Power Budget

2006, VDV Works LLC

Part 1

1.2 Fiber Optic Cable Types

Sep 19th 2012

VARIOUS TYPES OF

OPTICAL FIBER CABLESAerial types: 1. OPGW Cable

2.3.

ADSS type OF CableLASHED type OF Cable

UNDERGROUND types 1. 2. BURRIED type OF Cables DUCT Type OF Cable

Submarine types: Nepco have 2 fiber submarine cables (each of 12 fiber strands) laid between Aqaba to Taba at Egypt crossing Aqaba Gulf (13km) with the power cable that connects the power Grid between Jordan and Egypt at 400kv level .

Sep 19th 2012

Sep 19th 2012

Sep 19th 2012

Aerial FIBRE OPTIC CABLE INSTALLATIONOPGW

WRAP AROUND

ADSSSep 19th 2012

UNDERGROUND / BURRIED type OF Cables

Sep 19th 2012

DUCT Type OF Cable

Sep 19th 2012

Part 1

1.3 Fiber Optic Splicing

Sep 19th 2012

Fiber Splicing1. Fusion Splicing: through splice machine using electrodes, Nepco has different types of splice machines like Fujikura 40s , 50 s & 60 s 2. Mechanical Splicing: for connectors

Sep 19th 2012

Splicing at the Field

Sep 19th 2012

Fiber Optic Connectors & Splices Connectors Demountable terminations for fiber Connect to transmitters and receivers

Splices Permanent termination of two fibers 2006, VDV Works LLC

Part 1

1.4 Fiber Optic Testing

Sep 19th 2012

Fiber Optic TestingFiber testing is made through two main ways1. Laser source and power meter test : the motive of this test is to check the continuity of the fiber from end to end.

Sep 19th 2012

End to End Testing Both units must be referenced with the test jumpers Confirm power source is connected to test fiber Reading is only accurate if both units at same wavelength

Fiber Testing2. OTDR test: this test is done to check the quality of the trace including splice points , bending locations , optical reflection loss (ORL) and determine the location of any fault if exist through calculating the time and speed of the light

Sep 19th 2012

OTDR Trace

Sep 19th 2012

TEST AND MEASUREMENT INSTRUMENTS

OTDR

OPTICAL TALK SETS

POWER METER,Sep 19th 2012

TOOL KIT

LASER SOURCE, ATTENUATOR

Introduction to OTDR OTDR stands for Optical Time Domain Reflectometer, the main function of an OTDR is to detect, locate and measure all the events (splices, connectors, bending, etc..), an report the location of each event with accuracy ranges from 4 cm to 40 meters. An OTDR utilizes the idea of a RADAR you can think of it as a one dimensional RADAR, using OTDR we get a full report of losses as well as reflective events (connectors and mechanical splices) tied to the distance or the geographical information of an optical fiber link. OTDR makes use of the small signals those travel back the fiber, even by backscattering or by reflection comparing their power levels and arrival time with its sent signals it can generate a nice report of what events are on a fiber link.

Sep 19th 2012

Optical Fiber Standards IEC 60793-1 and -2: Optical fibers (includes several parts) IEC 60794-1, -2, and -3: Optical fiber cables G.651: Characteristics of 50/125 m multimode gradedindex optical fiber G.652: Characteristics of singlemode optical fiber and cable G.653: Characteristics of singlemode dispersion shifted optical fiber and cable G.654: Characteristics of cut-off shifted singlemode optical fiber and cable G.655: Characteristics of non-zero dispersion shifted singlemode optical fiber and cable G.656: Characteristics of non-zero dispersion shifted fiber for wideband transportSep 19th 2012

Part 2

2.1 Fiber Optic at Electric Utilities

Sep 19th 2012

Why Fiber at Electric Utilities1. It is there: As mentioned before ,OPGW fiber cables are installed on most of the OHLs in the transmission network because of its law cost .

2. Immunity to EMI , electric substations are full of noise and harmonics generated through switching operations .Sep 19th 2012

Why Fiber at Electric Utilities3. Greater Bandwidth: you can go up to 10ths of Gb/s using fiber cables which opens the door for vast number of applications and services

4. Lower attenuation: which means longer distances for the working sections connecting far places together into one network .Sep 19th 2012

Why Fiber at Electric Utilities5. Great revenues through fiber leasing.

Sep 19th 2012

National Electric Power Company Communication StrategyNEPCO communication strategy is based on diversity in communication equipment and media to ensure high availability rates without interruption for vital services, i.e digital power line carriers (PLC) which uses the phase conductor of the OHL for transmitting signals and data between substations is used as backup in case fiber cut occurs. NEPCO has built fiber rings and installed high speed TDM SDH multiplexers with rates starting from STM-1 level(155Mb/s) up to STM-16 (622Mb/s) to operate on the OPGW network in a single managed platform covering most of the substations.

Sep 19th 2012

Electric Utilities Communication NeedsMany communication needs for higher bandwidth have emerged in the past years for the power sector increasing the quality of the grid and they are as follows, 1. Powerful control center that controls all the substations in the network through Remote Terminal Units (RTUs) connected through communication channels in a secure and reliable way , SCADA system communication protocols has been developed from hundreds of baud rate up to Ethernet (100Mb/s), Nepco recently upgraded most of the SCADA communication channels through its fiber optic network

Sep 19th 2012

Electric Utilities Communication Needs

Sep 19th 2012

Electric Utilities Communication Needs2. Metering systems developed quickly and trends to remote readin

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