MRU3

Productomschrijving

Among other applications the relay can be used for detection of over- or undervoltages in power genrating plants and energy supply systems

• to protect generators against critical overvoltages in case of defective voltage regulators
• as undervoltage protection for motors
• as generator stator earth fault protection
• as over- and undervoltage protection with evaluating the symmetrical components (MRU1-2, detailed information on this type can be found in the relevant technical description)

There is also a similar protection relay IRU1 avail-able in a more simpler design, i.e. with less function, without display and without serial interface.

Features
• Microprocessor technology with watchdog,
• digital filtering of the measured values by using discrete Fourier analysis to suppress higher harmonics and d.c. components induced by faults or system operations,
• two parameter sets,
• voltage supervision each with two step under-/ and overvoltage detection,
• Completely independent time settings for voltage supervision
• display of all measuring values and setting parameters for normal operation as well as trip ping via a alphanumerical display and LEDs,
• display of measuring values as primary quantities
• 1-phase or 3-phase tripping criterion for the U step,
• Storage and display of tripping values in a fault memory (voltage-failure safe),
• recording of up to eight fault occurences with time stamp
• for blocking the individual functions by the external blocking input, parameters can be set according to requirement,
• suppression of indication after an activation (LED flash),
• free assignment for output relays,
• display of date and time,
• in compliance with VDE 0435, part 303 and IEC 255,
• serial data exchange via RS485 interface possible; alternatively with SEG Electronics RS485 ProOpen Data Protocol or Modbus Protocol.