Generator Relay

Provide proven primary and backup protection for utility and industrial generators to IEEE turbine protection standards. The SEL-300G Generator Relay is a comprehensive, multifunction relay intended for primary and/or backup protection for any size synchronous machine.

Applications

Complete Generator Protection—Connect the SEL-300G Generator Relay across large generators for complete primary and backup protection. Adding the neutral voltage connection provides 100 percent stator ground protection, based on third-harmonic voltage measurements. Connecting the neutral current input provides protection for solidly grounded or resistance-grounded machines.

Secure Remote Control and Monitoring—Use Modbus and ASCII communications capabilities for control, monitoring, and alarming. Control relay operation and initiate or block automation sequences from remote or local control systems.

Current Differential Protection—Apply sensitive percentage-restrained current differential elements and an unrestrained element, along with synchronism check and volts-per-hertz elements, to protect both the generator and the step-up transformer. The SEL-300G includes phase shift and magnitude difference compensation for current differential applications that include generator step-up transformers.

Overexcitation Detection—Detect overexcitation using volts-per-hertz elements in both the generator and step-up transformer. Choose from multiple curves and definite-time elements for alarm and tripping applications.