These relays provide protection for synchronous generators from extensive damage by detecting loss-of-field excitation. Benefits * Accurate protection provided by true var measurement. * Minimized CT and PT costs as a result of low sensing burden. * Reduced battery load with low burden power supply. * Accurate, repeatable, and reliable operation. * Simple HMI provides clear and intuitive settings for easy configuration. * LED targets provide clear annunciation of status. * Easily perform in-case system and device tests using test paddles.