Ensayos

MRI3-ITE(R) - Time overcurrent relay with thermal replica and earth current measuring

Contents 1 Introduction and Application 2 Features and characteristics 3 Design 3.1 3.1.1 3.1.2 3.2 3.2.1 3.2.2 3.2.3 3.3 Connections Analogue input circuits Output relays Relay output contacts Blocking input External reset input Fault recorder Front plate 5.4.7 5.4.8 5.4.9 5.4.10 5.4.11 5.4.12 5.4.13 5.4.145.4.15 5.4.16 5.4.17 5.4.18 5.4.19 5.4.20 5.4.21 5.4.22 5.4.23 5.4.24 5.5 5.5.1 5.5.2 5.5.3 5.5.4 5.6 5.7 5.7.1 5.8 5.8.1 5.8.2 5.8.3 5.8.4 5.9 5.9.1 5.9.2 Trip delay or time multiplier for phase overcurrent element (tI>) Reset setting for inverse time tripping characteristics in the phase current path Current setting for high set element (I>>) Trip delay for high set element (tI>>) Pickup valuefor residual voltage UE (ITER-relay type) Pickup current for earth fault element (IE>) WARN/TRIP changeover Time current characteristics for earth fault element (CHAR IE) (not ER device type) Trip delay or time multiplier for earth fault element (tIE>) Resetting time for inverse time earth fault element (not ER-relay type) Current setting for high set element of earth fault supervision (IE>>) Tripdelay for high set element of earth fault supervision (tIE>>) COS/SIN Measurement (ER - relay type) Block/Trip – time (only ITE-device type) Circuit breaker failure protection tCBFP Adjustment of the slave address Setting of Baud-rate (applies for Modbus Protocol only) Setting of parity (applies for Modbus Protocol only) Fault recorder Adjustment of the fault recorder Number of the faultrecordings Adjustment of trigger occurrences Pre-trigger time (Tpre) Adjustment of the clock Additional functions Blocking of the protective functions Indication of measuring and fault values Indication of measuring values Unit of the measuring values displayed Indication of fault data Fault memory Reset Erasure of fault storage Reset of the thermal replica register

4 Working principle 4.1 Analogcircuits 4.2 Digital circuits 4.3 Thermal replica 4.3.1 Definitions 4.4 Algorithm 4.5 Earth fault protection 4.5.1 Generator stator earth fault protection 4.5.2 System earth fault protection 4.6 Earth-fault directional feature (ER-relay type) 4.7 Demand imposed on the main current transformers 5 Operation and settings 5.1 Display 5.1.1 LEDs 5.2 Setting procedure 5.3 System parameter 5.3.1 Display ofmeasuring values as primary quantities (Iprim phase) 5.3.2 Display of earth current as primary quantity (Iprim earth) 5.3.3 Display of residual voltage UE as primary quantity (Uprim/Usec) 5.3.4 Voltage transformer connection for residual voltage measuring (3pha/e-n/1:1) 5.3.5 Nominal frequency 5.3.6 Display of the activation storage (FLSH/NOFL) 5.3.7 Parameter switch/external triggering of the faultrecorder 5.4 Protection parameters 5.4.1 Pickup value of the thermal overload protection IB,A and IB,T 5.4.2 Constant k 5.4.3 Energising delay (time )for the thermal overload 5.4.4 Time constant τ 5.4.5 Pickup current for phase overcurrent element (I>) 5.4.6 Time current characteristics for phase overcurrent element (CHAR I>)
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TD_MRI3-ITE(R)_05.04_GB

6 Relay testing and commissioning 6.1Power-On 6.2 Testing the output relays and LEDs 6.3 Checking the set values 6.4 Secondary injection test 6.4.1 Test equipment 6.4.2 Example of test circuit for MRI3-ITE 6.4.3 Checking the input circuits and measured values 6.4.4 Example of a test circuit with earth fault directional feature 6.4.5 Checking the operating and resetting values of the relay 6.4.6 Checking the relay operating time6.4.7 Checking the high set element of the relay 6.4.8 Checking the external blocking and reset functions 6.4.9 Testing the external blocking with Block/Trip function 6.4.10 Test of the CB failure protection 6.5 Primary injection test 6.6 Maintenance 7 Technical data 7.1 Measuring circuits 7.2 Common data 7.3 Setting ranges and steps 7.3.1 Systemparameter 7.3.2 Overload protection 7.3.3 Overcurrent...