Efacec, the largest electricity solution corporation in Portugal, is a multinational corporation that employs around 4000 people and processes over 1000 million Euros in orders annually. Efacec has a presence in over 50 countries and exports half of its production. Sonelgaz, the electricity generation, transmission, and distribution company owned by the government of Algeria, looked to Efacec to supply automation systems for four new substations. Sonelgaz had two transmission substations and two distribution substations that all needed to establish communications between the central units, the bay control units, and the digital protection relays while meeting the IEC 61850 standard. Efacec chose Moxa’s PowerTrans PT-7728 series IEC 61850-3 compliant Ethernet switches to provide the necessary communications backbone and IP connectivity for the substation automation systems.

‧ Non-stop operation for mission-critical applications
‧ Network devices that are IEC 61850-3 and IEEE 1613 compliant 
‧ Modular rackmount capacity and rear cabling with front display for ease of installation and maintenance

To obtain the benefits of IEC 61850, the underlying communications backbone must operate reliably in harsh substation environments. This is why IEC 61850 also specifies environmental criteria for EMI immunity. Efacec chose Moxa's products to construct a rugged substation backbone because Moxa's PowerTrans products are designed for substation environments and have passed IEC 61850-3 and IEEE1613 certification testing conducted by KEMA, a well respected independent consulting and testing laboratory for certification services in the energy and utility markets.

Moxa's PT-7728 IEC 61850-3 compliant Ethernet switches are deployed in a 400kV transmission substation automation system to connect with protection relays and other intelligent electronic devices (IED), together forming a Gigabit ring topology protected by the RSTP protocol to guarantee recovery in the event of network failure. The PT-7728 comes equipped with four Gigabit ports that provide the power needed for a redundant Gigabit Ring backbone, and leaves a spare Gigabit port for uplink to the core switches. Additionally, several PT-7728 Ethernet switches are connected to the SCADA monitoring local server and the substation redundant central units, to give system operators an efficient way to monitor operations at the field sites. Also, the modular rack mount design with rear cabling and front display is easy to install and maintain.

By having a highly reliable and future-proof communications network designed specifically for substation environments, Sonelgaz is able to reap the benefits of IEC 61850 and achieve the project goals associated with the substation modernization program.

‧ The PowerTrans PT-7728 series supports the demands of power substation automation systems as described in the IEC-61850 directive
‧ Non-stop operation is the key criterion for mission-critical applications. The PowerTrans supports dual, isolated, redundant power supplies with 88 to 300VDC power inputs
‧ Modular rack mount capability, rear cabling access, and an easily readable product front display were all crucial for this project.