STATUS OF TELECOMMUNICATIONS SYSTEM AND O&M PRACTICES IN ELECTRIC POWER INDUSTRY OF SERBIA (EPS) Danilo Lalović, Senior Engineer for Telecommunications

1. Deregulation in energy sector Reorganization process of integral Serbian electric power industry was completed in the past establishing two independent technical business systems: JP Electric Power Industry of Serbia JP Serbian Transmission System (EMS)-in charge of Electric Power Transmission and Transmission System operator

2. Company Information Electric Power Industry of Serbia (EPS) is public enterprise which is vertically organized and composed of 11 Economic Associations. Main activities are : Electric power generation Electric power distribution and distribution system management Coal production, processing and transport Electric power trade

3. New Telecommunications System of EPS Project of building new Telecommunications system is mostly finalized. Main requirements have been achieved to fulfill the communications needs for technical and business management systems of the company. Telecommunications links to the neighboring electric power industries are established. Spare capacity in the backbone network can be utilized in the future for entering into the market providing commercial services.

4. Project Implementation Status EPS Backbone network is based on OPGW cables and currently there are around 6000 km of the cables deployed on high voltage (400 kV, 220 kV and 110 kV) and middle voltage (35 kV) transmission lines. Generally cables are composed of 48 fibers in mixed structure, half of them are according the ITU-T G.652 and the other half according the ITU-T G.655B Recommnedation. There are currently 80 telecommunications nodes installed in the network providing the services for utility needs. Building of the new Telephone exchange network based on IP technology is finalized. The core IP network is based on MPLS routers and communications between them is through SDH network.

The telecommunications network is based on SDH technology and has mesh structure covering all the important substations and power plants in EPS. The current capacity on most of the links is STM-16. The number of deployed nodes (80) will increase over time as we approach distribution companies and start solving regional communications needs. Network management is centrally organized from one location. However there exists also disaster recovery servers system on back up location which can take over the management of the network at any time. 5. EPS Telecommunications Network

Optical Structure of EPS Backbone

SDH Network Architecture

6. Telecom Policy and Organization The main policy is to build dedicated telecom network with the highest possible availability and reliability for utility services. Telecom entity organization is established within EPS as centralized in-house unit but with the idea to transform it into EPS daughter company in the future. The telecom organization is not currently integrated with IT unit. The organization is currently engaging 5 professionals with the tendency to grow over time as the system develops. The model of outsourcing is used for running the telecom organization. In house unit is taking full responsibility for realization of telecom services as well as their monitoring and eventual rectification of the occurred problems. There is also an idea to become Telecom Operator for State Institutions as well as to enter Telecom Market and provide commercial services.

7. Operation and Maintenance Practice The model of outsourcing comprises of the following categories of activites: Help Desk Services Corrective Maintenance Preventive Maintenance Operational Services

Operation and Maintenance Practice Help Desk 5x8 Contractor is obligated to provide practical guidance for EPS personal during normal working hours. Service is realized as help desk and communication is done by or by phone. Contractor is responsible to provide support with less than ten minutes response time for the 1.st line supported personal and less than 30 minutes for specialist personnel support

Operation and Maintenance Practice Corrective maintenance Severeity level 1 Defect or fault situation defined as critical alarm in the NMS or problem that affects critical services like SCADA services. Problem resolving starts 30 minutes after notification Within 8 h on-site

Operation and Maintenance Practice Corrective Maintenance Severeity level 2 Problems defined as major alarms in the network. NBD (Next Business day) on site. Severity level 3 Minor alarms, warnings, within one week on-site Remote support Off site problem solving

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Operation and Maintenance Practice Spare Parts are maintained in EPS store and its availability is EPS responsibility. Preventive Maintenance At each individual site this includes General observation and reporting of equipments hardware conditions General observation and reporting of equipment room’s conditions with regard to temperature, clean air and status of anti rodent protection Cleaning of ef equipment fans 48 V Power System Control The interval between periodic preventive actions at each site is six months.

Operation and Maintenance Practice Software upgrades includes upgrade of system software components with new software releases and service packs. Backup services include periodic backup actions like backup of node configuration files. It is performed periodically. If some configuration changes are done, then backup will be performed simultaneously, if not, then backup interval will be one week.

Operation and Maintenance Practice Operation and administration services cover daily activities in the network necessary for services setup and network monitoring like: Provisioning which includes Creation of new network services (connections) by means of software commands executed at the SDH and/or FMUX NMS. Modifying or removing of network services (connections) by means of software commands executed at the SDH and/or FMUX NMS

Operation and Maintenance Practice Operation Services Network reconfiguration which includes: Hardware reconfiguration services - moving cards or nodes between sites, installation and testing of new cards Software reconfiguration services - reconfiguration of initial network parameters like addresses, routing plans, management parameters, synchronization On site set up services which include activities on site, like patch-cabling and customer equipment cabling (connection to the network).

Operation and Maintenance Practice Operational Services Network monitoring Network monitoring includes continuous monitoring of network by NMS with objective to quickly detect faults and defect situation and initiate corrective actions. Administration of NMS system (maps, users, security…).

Main Risks The most frequent problem in the network appears to be rodent attack and we have to improve anti rodent protection in telecom facilities. Optical fiber breakage or damage is seldom. However the repair is dependent on switching off the power line and might be time consuming to get the permit for the works. There is also an idea to implement Optical Fiber Monitoring System which could bring better control and improve reliability of optical network through preventive actions. Problems with power supply systems sometimes cause difficulties for Telecom System. Remote monitoring of 48 V power supply system and its inclusion into NMS could bring benefits through preventive actions.

Future Development EPS currently mainly outsources Operation and Maintenance and telecom unit is under staffed for this activity. We forsee certain growth of telecom organisation, in charge of network with extensive coverage, in order to balance outsourcing activites to the extent of running the network and perform basic O&M activites, This is necessary in order to secure sufficient knowledge and expertise within in house unit which can provide future development and upgrade of the network as well as to avoid situation of complete dependence on outsource expertise. Vendors expertise and support has to be a part of O&M model.