RXBA - Fuse supervisory relay

RXBA 4 is a static, three-phase relay that detects fuse failures by comparing the voltages on both sides of the fuse in each phase. It detects single-, two- or three-phase fuse failures in less than 8 ms, and is used to block high-speed distance protection relay tripping in case of fuse failure.

RXBA 4 can also be used to block other protection relays where fuse failure will cause unnecessary tripping such as undervoltage relays, underimpedance relays, etc.

• Detects failures on both main and pilot fuse groups
• Can be used with miniature circuit breakers
• Contact outputs for blocking and alarm of failures on main and pilot fuse group
• Needs no auxiliary supply
• LED indication of faulty fuse