MRZS-U

Performs the following functions

Control and measurement

• ­ three phase or line voltages (main channel) from TV1 installed on the busbars;
• two-line voltages of auxiliary channel from ТSC or one line voltage from TV2, set at the input;
• zero phase-sequence voltage.

Relay protection functions:

• three-stage undervoltage protection PVmin operates with a time delay for tripping or by signal;
• three-stage overvoltage protection PVmax operates with a time delay for tripping or by signal;
• two-stage ground fault protection according to 3Uo
• two-stage reverse sequence voltage protection;
• maximum voltage protection of auxiliary channel operates with a time delay for tripping or by signal output;
• total protection of the minimum voltage of primary and secondary channels;
• arc protection (AC): the AC is started via a discrete input or from external fiber-optic arc protection sensors with the possibility of monitoring phase voltages;
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• universal protections (8 pcs.) with the possibility of starting on phase or line voltages, 3Uо, U1, U2, frequency, rate of change of frequency. At the same time, the trigger can act as an overshoot setpoint, and to decrease below the setpoint.

Automation functions:

• ACR with CHAPV - four degrees;
• ACB start up;
• Startup of the normal mode restoration (NMR) scheme at ACB

Monitoring, registration and alarm functions:

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• monitoring of serviceability of voltage circuits of main and auxiliary channels;
• detection of a disconnected circuit breaker TV
• emergency registrar of oscillograms 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 duration record - 50 sec.
• discrete signal recorder:
• 48 recent events;
• up to 43 records in each alarm with a fixed value;
• ­ maximal/minimal voltages (voltages of phases and 3Uo, U2), frequency.

Enhanced logic functions:

• ­ number of defined functions - 8;
• ­ number of defined triggers - 3;
• status of triggers is stored in non-volatile memory.
• transmission functions:
• communication 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;
• integrity check of sensors and arc protection circuit;
• six freely programmable buttons with the ability to operate in "key" mode;
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• control buttons for the switch; ;
• 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 of your choice:
• ­Interface of your choice:
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• Ethernet interface (RJ-45) - IEC 61850 exchange protocol (optional);
• Ethernet interface (optical ST) - IEC 61850 exchange protocol (optional).