MRZS-F

Performs the following functions

Control and measurement

• phase currents at a frequency of 50 Hz with a nominal value Iн = 5 A in the range from 0.1 to 30 Iн;
• current of one phase of 0.4 kV connection - from 0.5 to 150A;
• zero sequence current from 0.01 to 2 A;
• currents of positive and reverse sequences;
• three phase or line voltages - up to 150 V;
• zero phase-sequence voltage up to 150 V;
• angles between all analog line measurements;
• network frequencies;
• active power with a sign;
• reactive power with a sign;
• full power;
• power factor;
• inter-phase active and reactive resistances.

Relay protection functions:

• four-stage overcurrent protection (OCP), has the following stages:
• 1 stage with definite time delay (current pinch-off), or with the possibility of a voltage triggering, or directional OCP with an independent time delay;
• 2 stage with an indefinite time delay with the possibility of voltage triggering or with a definite time delay (in accordance with IЕС 255-4 types A, B, C, characteristics RТ-80, RТV-1), or directional OCP with indefinite time delay;
• 3 stage with a definite time delay (overload protection) with the possibility of voltage triggering or directional OCP;
• 4 stage with a definite time delay (overload protection) with the possibility of voltage triggering or directional OCP.
• Blocking of OCP the throws of current of magnetizing;
• two-stage single-phase overcurrent protection 0.4 kV, 1st stage with indefinite time delay, 2nd stage with definite or indefinite time delay in accordance with IEC 255-4;
• negative phase-sequence protection (NPSP), reacts to the ratio of the negative sequence current to the direct sequence current (phase failure monitoring (PFM));
• arc fault protection (AFP): AFP launch is carried out through a discrete input or from external fiber-optic arc protection sensors with the ability to control phase currents, voltages in any combination or 3Io;
• directional ground fault protection DGFP: angle between the current 3Io and the voltage 3Uo (the current is behind the voltage) corresponding to the middle of the operating zone is equal to 90 deg; protection operation region by the angle from 0 ± 10 degrees to 180 ± 10 degrees; operates on the forward or reverse power direction;
• indirected ground fault protection by 3Iо, (analogue of the relay PTZ-51) or by the sum of the higher harmonics 3Io;
• three-stage directional ground fault protection according to design 3Io (GFP) with the possibility of simultaneous operation in two directions with different sets of settings.
• two-stage undervoltage protection ЗНmin;
• two-stage overvoltage protection ЗНmax;
• zero-sequence voltage protection 3Uo (РНН) operates with or without time delay;
• circuit-breaker failure protection (CBFP) with current control: breaker failure protection is initiated at OCP response to cut-off or via discrete input. The breaker failure protection has two stages in response time.
• universal protection (8 ps.) with the possibility of starting by phase currents, current 3Io, the sum of the higher harmonics 3Io, 11, 12, design current 3Io, 0.4 kV current, phase or line voltages, 3Uo, U1, U2, active, reactive and full power. In this case, the fault detector can operate both on the excess of the setpoint and on a decrease below the setpoint.
• deshunting function of two current circuits.

Automation functions:

• circuit breaker control. The circuit breaker can be switched on and off both from the device and via a discrete input (pulsed). If there is a command to cut off the circuit breaker, the on signal is blocked;
• acceleration of protection. The automatic acceleration of the OCP of the second stage is entered at the command of the circuit-breaker;
• four-time recloser (AR). The AR is started from the OCP. If a blocking signal is present at the discrete input, the inhibition of the reclosure is carried out, if it disappears, the inhibition of reclosure is removed;
• UFLS with FAR - 2 stages.

Monitoring, registration and alarm functions:

• determining the fault location;
• circuit breaker closing and opening monitoring;
• control of commutation life of switch;
• emergency registrar of oscillograms of currents with recording of discrete signals:
• parameterizable duration of pre-emergency and emergency recording;
• resolution capability of the recorder by analog signals - 1,25 ms;
• total recording time - 50 s.
• discrete signal recorder:
• 30 recent events;
• up to 43 records in each alarm with a fixed value:
• maximum phase current;
• maximum current 3Iо;
• maximum voltage 3Uо;
• maximum phase or line voltage;
• minimum phase or line voltage;
• maximum ratio of the negative sequence current to the positive sequence current;
• maximum rated current 3Iо;
• minimum frequency for UFLS1 or UFLS2 operation;
• frequencies at the time of the FAR1 or FAR2 commands;
• statistics recorder: records the last 400 changes of all discrete signals;
• technical metering of electricity:
• active energy in two directions;
• reactive energy in four quadrants.

Short-circuit current auxiliary power supply. If the power supply of the device at the power input of 220 V (or 110 V) The device can be powered from current transformers of phases A and C. In this case, the magnitude of the current must be 4 A or more for one of the phases or for the total of two phases.

Supply of two discrete inputs from internal power source (DIР)

Enhanced logic functions:

• number of defined functions - 8;
• number of defined triggers - 4;
• status of triggers is stored in non-volatile memory;
• transfer functions;
• logical elements AND, OR, NOT, EXCLUSIVE-OR.

Enhanced logic allows to complement existing functions and create new ones.

Service functions:

• freely assignable inputs;
• freely assignable outputs;
• freely assignable LEDs;
• four groups of settings for all protections;
• monitoring the integrity of the sensors and the arc protection path;
• multilingual menu - 3 languages supported;
• six freely programmable buttons with the ability to operate in key mode;
• switch control buttons;
• work with an external computer is carried out through the USB port.

Interfaces and communication protocols:

• Interface RS 485 - Communication protocol Modbus RTU;
• Interface USB;
• Interface by choice:
• Interface Ethernet (RJ-45)- Communication protocol IЕС 61850 (optional);
• Interface Ethernet (optic)- Communication protocol IЕС 61850 (optional).