The L30 is a cost-effective line current differential protection relay intended for sub-transmission and medium voltage lines and cables providing reliable and secure operation even under the worst case power system conditions. The L30 provides secure high-speed fault detection and clearance suitable for three-pole tripping applications. The L30 supports inter-relay communications via direct fiber as well as standard RS422, G.703 and C37.94 telecommunication interfaces. The L30 also provides synchrophasor measurements over Ethernet per IEEE C37.118.
       						
       						    					
       						
    							Applications
	- Overhead lines and underground cables of different voltage levels
 
	- Circuits with tapped transformer feeders
 
	- Suitable for three-terminal line configurations, with channel redundancy and direct transfer tripping (DTT)
 
	- Wide area system monitoring and control and using integrated protection and synchrophasor measurement
 
	- Applications requiring three-pole autoreclosing and independent synchrocheck supervision
 
Key Benefits
	- Proven current differential protection ensures secure  high-speed tripping
 
	- Increased sensitivity through dynamic charging current compensation and communication channel asymmetry compensation
 
	- Adaptive restraint characteristic provides excellent security against measurement errors including CT saturation
 
	- In-zone power transformer functionality enables savings on CTs and protection device requirements
 
	- Phasor Measurement Unit (synchrophasor) according to IEEE® C37.118 (2011) and IEC® 61850-90-5 support
 
	- Three independent fiber or copper Ethernet ports for simultaneous/dedicated network connections with advanced 1 microsecond time synchronization via LAN with IEEE 1588 support
 
	- Complete IEC 61850 Process Bus solution provides resource optimization and minimizes total P&C life cycle costs
 
	- Increase network availability by reducing failover time to zero through IEC 62439-3 "PRP" support
 
	- CyberSentry™ provides high-end cyber security aligned to industry standards and services (NERC® CIP, AAA, Radius, RBAC, Syslog) 
 
	- Advanced fault and disturbance recording, including internal relay operating signals, eliminating the need for external recording devices
 
Functional Block Diagram