MRZS -L

Performs the following functions

Control and measurement

• phase currents;
• zero sequence current, direct and reverse sequences;
• three phase or line voltages;
• zero sequence voltages, direct and reverse sequences;
• angles between all analog line measurements;
• network frequencies;
• active power with a sign and reactive power with a sign;
• full power and power factor;
• active energy - in two directions and reactive energy - in four quadrants
• phase and inter-phase active, and reactive resistances.

Relay protection functions:

• four-stage distance protection (DP) with sector characteristic, with an undirected first stage and the ability to choose the direction and width of the sector of the second, third and fourth stage; minimum resistance value - 0.01 Ohm;
• four-stage overcurrent protection (OCP), can be of two versions, optionally:
• 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 definite time delay with the possibility of voltage triggering or with a time-dependent delay (in accordance with IES 255-4 types A, B, C, RТ-80, RТV-1 characteristics), or directional OCP with an independent time delay;
• 3 stage with a definite time delay (overload protection) with the possibility of voltage triggering or directional OCP;
• 4 directi stage with a definite time delay (overload protection) with the possibility of voltage triggering or onal OCP.
• 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: with the choice of the direction of action and the possibility of switching to non-directional (with respect to the current 3Io or voltage 3Uo) or to a non-directional 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;
• two-stage overvoltage protection;
• circuit-breaker failure protection (CBFP) with current control: CBFP is initiated when cut-off tripping events or via a binary input. CBFP has two stages in response time.
• universal protection (8 ps.) with the possibility of starting with phase currents, 3Io, I1, I2, phase or line voltages, 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.

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 - 66 s.
• discrete signal recorder:
• 30 recent events;
• up to 43 records in each alarm with a fixed value: maximum phase current, voltage, frequente;
• technical metering electricity:
• active energy in two directions;
• reactive energy in four quadrants.

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).