Protection and Monitoring
Add simple bus protection using contact inputs and outputs from existing relays. Add secure pilot communications to existing two- and three-terminal line applications. Add local or remote trip- and close-coil monitoring capability.

User-Configurable Labels
Allow clear indication of system function and status.

Integration
Expand the I/O of SEL relays that are Mirrored Bits-compatible.

Flexible Communications
Connect between devices with the included RS-232 port, or select the optional SEL-2812–compatible fiber-optic port for communication with electrical isolation up to 4 km apart.

Safety
Replace control wiring to outside cabinets with fiber-optic cable to eliminate paths for dangerous voltages. All I/O terminals are behind the panel.

Dependability
Use the communications monitoring feature to alarm when fiber-optic control cabling has been damaged, disturbed, or altered. Fiber-optic links are far less susceptible to electrical interference.

Easy Installation and Service
Install the rack-mount, compact two-rack-unit chassis. The SEL-2507 includes screw-terminal connector (STC) blocks for easy replacement of the unit.