The UFR1001E system-disconnection relay monitors voltage and frequency in single or three-phase networks. It complies with the conditions and all the requirements of G98 and G99 -protection, for feeding into the low voltage grid and for feeding into the medium voltage grid. When using with generators, the evaluation of feedback contacts for the period of a shut-down and during the synchronisation can be suppressed.
The UFR1001E has two channels which makes it more fail-safe; input circuitry, evaluation and output relay are provided in duplicate. Two processors monitor each other mutually. Feedback contacts are used to monitor the functioning of both output relays and the section switch. During an alarm both channels shut down, the cause is displayed, and it is reported through digital outputs, separate DC power supply required.


Applications include monitoring the network in generating plants, such as solar arrays, wind turbines, CHP Installations and diesel generator connected to the mains for Co-generation or peak lopping applications. Offering U/O Voltage and Frequency, as well as ROCOF the UFR1001E suits all installation types. The device complies with the requirements of the public utility power providers for conventional protection in low and medium voltage systems >30 kVA.
  • Pre-setting per G98 and G99, VDE-AR-N 4105, BDEW, ÖVE/ÖNORM E 8001-4-712
  • Under and overvoltage monitoring 40…520 V
  • Measurement 3 / 2 / 1 phases against N and/or phase-phase
  • Under and over frequency monitoring 45…65 Hz
  • Monitoring the voltage quality (10-minute average value)
  • Fail-safe, with monitoring of the connected section switch (can be switched off), 2 automatic restarts on error
  • Passive autonomous system detection in accordance with Chapter 6.5.3 and Appendix D2
  • Monitoring of Rate of Change of Frequency (ROCOF, df/dt) connectible
  • Supports the mains synchronisation when using generators
  • Self-test
  • Response time adjustable 0.05 … 130.0 s, individual setting for each limit
  • Reset time adjustable 0 … 999 s, individual setting for each limit
  • Reset time 5s at limit violation < 3s
  • Alarm counter for 100 alarms (with trip value, cause and rel. time stamp)
  • Record of the cumulative time of alarms
  • Standby input with counter and time memory
  • Test button, simulation function, measurement of the shut-down times
  • LEDs for alarm signals, measurement value allocation and relay status
  • Sealing facility and code protection for settings, values can also be read in the sealed state
  • Simple commissioning and programming through 6 basic programs with preset limits
  • Message outputs for general alarm and for forwarding the cause of switching to the upstream controller (transistor, max. DC 27 V, 20 mA)

Medium voltage

  • Per 2×2 limits for voltage and frequency: U<<, U<, U>, U>>, F<<, F<, F>, F>>
  • Hysteresis, response and reset value individually adjustable
  • Control voltage AC/DC 24-270 V
  • Distributor housing V6, 6 TE 105 mm wide, front-to-back size 55 mm