Used as protection of the feeder cable and overhead lines (networks with compensated and uncompensated capacitive currents). Especially convenient for operation on overhead lines with a cable insertion or cable lines using protection in ombination - earth faults + phase failure without a short to ground (single-phase current conditions).
Performs the following functions:
Provides control and measurement of the following values:
- phase currents at a frequency of 50 Hz with a nominal value Iн = 5 A in the range from 0.1 to 30 Iн;
- zero-phase-sequence current from 0.01 to 2 A.
Relay protection functions:
- three-stage overcurrent protection (OCP), can be of two versions, optionally:
- 1) three-stage OCP with current indefinite time delay;
- 2) three-stage OCP, where the first and third stages with a current indefinite time delay and the second - with a current definite time delay, has a characteristic of the relay RT-80. The operating time of the second-stage OCP type RT-80 is determined by the formula: t-time of operation; I - input current; Iset - current setting of the second-stage of the OCP; Tset - is the set-point for the time of operation of the second stage of the OCP.
- Return rate of the fault detector not more than 0,95.
- single-stage negative phase-sequence protection (NPSP), responds to a negative sequence current.
- earth fault current protection 3Io, operates with or without shutdown delay or signal, non-directional, can be of two versions of choice:
- 1) protection reacts to the zero-sequence current of the industrial frequency 3I0;
- 2) protection reacts to the residual harmonic currents of the higher harmonics (HAEFPTOC).
- circuit-breaker failure protection (CBFP) with current control: circuit-breaker failure protection is initiated at OCP response to cut-off or via discrete input. The circuit-breaker failure protection has two stages in response time.
- switch 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. Automatic acceleration of the second stage overcurrent protection is entered at the command of the circuit breaker closing;
- single-stage autoreclosing (AR). The AR is started from OCP. If a blocking signal is present at the discrete input, the blockage of the AR is carried out, if it disappears, the AR blockage is removed;
- UFLS (FAR). When the "UFLS/FAR" signal appears on the discrete input, the circuit breaker is switched off. When the signal disappears at the input, the AR starts.
- number of defined functions - 5;
- the source commands of the functions being defined can be other defined functions, discrete inputs, discrete outputs, and protection operation.
Event logger of disturbance recorder oscillograms
- parameterizable recording time:
- pre-emergency process - from 0,1 to 5 s.
- emergency process - 1 to 20 s.
- total length of records - 150 s.
Discrete event recorder:
- 100 recent events;
- up to 50 entries in each accident with a discreteness in time - 1 ms;
- for each accident the following are recorded:
- all discrete signals during the time of presence of the trigger signal of the recorder;
- the maximum value of the phase current with the registration of the remaining currents at the moment of fixing the maximum current, when the protection is operating in phase currents;
- the maximum value of the current is 3Io with the registration of the remaining currents at the moment of fixing the maximum current, when the current protection is 3Io;
- the maximum value of the negative sequence current with the registration of the remaining currents at the moment of fixing the maximum current, with the operation of the negative sequence current protection.
Number of freely programmable inputs, outputs, indicators:
- discrete inputs - 5;
- discrete relay outputs - 6;
- LED indicators - 6.