SEL 2505 Remote IO Module

The SEL 2505 remote io module has eight digital inputs, eight digital outputs, and a fiber-optic communications port. Use two optical fibers instead of 32 wires between outdoor or remote equipment and the control building to reduce costs, improve safety, and boost reliability. Or, connect an SEL-2505 to a fiber-optic port or transceiver on a protective relay to add digital I/O. Wire the SEL-2505 I/O to relay I/O to add  SEL Mirrored Bits teleportation.

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  • 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.
  • Integration
    Expand the I/O of SEL relays that are Mirrored Bits compatible without modification to the control panel face. Make I/O status from any relay available to SEL Mirrored Bits schemes.
  • Safety
    Replace control wiring to outside cabinets with fiber-optic cable to reduce dc ground exposure.
  • Dependability
    Use the communications monitoring feature to alarm when fiber-optic control cabling has been damaged, disturbed, or altered.
  • High Reliability and Rugged Design
    Built to the same high standards as SEL protective relays, the SEL-2505 withstands vibration, electrical surges, fast transients, and extreme temperatures, meeting stringent industry standards. The printed circuit boards are conformal-coated to provide an additional barrier to airborne contaminants, such as hydrogen sulfide, chlorine, salt, and moisture.
  • Savings
    Reduce project costs by using two fibers instead of 32 large-diameter wires, with less material expense, reduced trench and raceway requirements, and less labor for design, documentation, installation, testing, and maintenance.