User manual WOODWARD SEG MRI1

[. . . ] MRI1 - Digital multifunctional relay for time overcurrent protection L1 L2 L3 E IP IQ RS SELECT/RESET t I> IE > CHAR I> UE > tI > ENTER t I> I>> tI>> TRIP E IE >> tI E >> PHASE EARTH I MRI1-IRER 1 Introduction and application 2 Features and characteristics 3 Design 3. 1 Connections 3. 1. 1 Analog input circuits 3. 1. 2 Output relays of MRI1-relays 3. 1. 3 Blocking input 3. 1. 4 External reset input 3. 2 Relay output contacts 3. 2. 1 Parameter settings 3. 3 LEDs 4 Working principle 4. 1 Analog circuits 4. 2 Digital circuits 4. 3 Directional feature 4. 4 Earth fault protection 4. 4. 1 Generator stator earth fault protection 4. 4. 2 System earth fault protection 4. 5 Earth-fault directional feature (ER/XR-relay type) 4. 6 Determining earth short-circuit fault direction 4. 7 Demand imposed on the main current transformers 5 Operation and setting 5. 1 Display 5. 2 Setting procedure 5. 2. 1 Pickup current for phase overcurrent element (I>) 5. 2. 2 Time current characteristics for phase overcurrent element (CHAR I>) 5. 2. 3 Trip delay or time multiplier for phase overcurrent element (tI>) 5. 2. 4 Reset setting for inverse time tripping characteristics in the phase current path 5. 2. 5 Current setting for high set element (I>>) 5. 2. 6 Trip delay for high set element (tI>>) 5. 2. 7 Relay characteristic angle RCA 5. 2. 8 Voltage transformer connection for residual voltage measuring (3pha/e-n/1:1) 5. 2. 9 Pickup value for residual voltage UE (ER/XR-relay type) 5. 2. 10 Pickup current for earth fault element (IE>) 5. 2. 11 WARN/TRIP changeover (E/X and ER/XR-relay type) 5. 2. 12 Time current characteristics for earth fault element (CHAR IE; (not for ER/XR-relay type) 5. 2. 13 Trip delay or time multiplier for earth fault element (tIE>>) 5. 2. 14 Reset mode for inverse time tripping in earth current path 5. 2. 15 Current setting for high set element of earth fault supervision (IE>>) 5. 2. 16 Trip delay for high set element of earth fault supervision (tIE>>) 5. 2. 17 COS/SIN Measurement (ER/XR-relay type) 5. 2. 18 SOLI/RESI changeover (SR-relay type) 5. 2. 19 Circuit breaker failure protection tCBFP 5. 2. 20 Nominal frequency 5. 2. 21 Display of the activation storage (FLSH/NOFL) 5. 2. 22 Adjustment of the slave address 5. 2. 23 Setting of Baud-rate (applies for Modbus Protocol only) 5. 2. 24 Setting of parity (applies for Modbus Protocol only) 5. 2. 25 Blocking the protection functions and assignment of the output relays 5. 3 Setting value calculation 5. 3. 1 Definite time overcurrent element 5. 3. 2 Inverse time overcurrent element 5. 4 Indication of measuring and fault values 5. 4. 1 Indication of measuring values 5. 4. 2 Indication of fault data 5. 4. 3 Fault memory (not for ER/XR types) 5. 5 Reset 6 Relay 6. 1 6. 2 6. 3 6. 4 6. 4. 1 6. 4. 2 testing and commissioning Power-On Testing the output relays and LEDs Checking the set values Secondary injection test Test equipment Example of test circuit for MRI1 relays without directional feature 6. 4. 3 Checking the input circuits and measured values 6. 4. 4 Checking the operating and resetting values of the relay 6. 4. 5 Checking the relay operating time 6. 4. 6 Checking the high set element of the relay 6. 4. 7 Example of a test circuit for MRI1 relay with directional feature 6. 4. 8 Test circuit earth fault directional feature 6. 4. 9 Checking the external blocking and reset functions 6. 4. 10 Test of the CB failure protection 6. 5 Primary injection test 6. 6 Maintenance 2 TD_MRI1_06. 05_GB 7 Technical data 7. 1 Measuring input circuits 7. 2 Common data 7. 3 Setting ranges and steps 7. 3. 1 Time overcurrent protection (I-Type) 7. 3. 2 Earth fault protection (SR-Type) 7. 3. 3 Earth fault protection (E/X-Type) 7. 3. 4 Earth fault protection (ER/XR-Type) 7. 3. 5 Switch failure protection 7. 3. 6 Interface parameter 7. 3. 7 Inverse time overcurrent protection relay 7. 3. 8 Direction unit for phase overcurrent relay 7. 3. 9 Determination of earth fault direction (MRl1-ER/XR) 7. 3. 10 Determination of earth fault direction (MRl1-SR) 7. 4 Inverse time characteristics 7. 5 Output contacts 8 Order form TD_MRI1_06. 05_GB 3 1 Introduction and application 2 Features and characteristics The MRl1 digital multifunctional relay is a universal time overcurrent and earth fault protection device intended for use in medium-voltage systems, either with an isolated/compensated neutral point or for networks with a solidly earthed/resistance-earthed neutral point. · The protective functions of MRI1 which are implemented in only one device are summarized as follows: · Independent (Definite) time overcurrent relay. · Inverse time overcurrent relay with selectable characteristics. · Integrated determination of fault direction for application to doubly infeeded lines or meshed systems. [. . . ] The selected assignment can be stored by pressing push button <ENTER> and subsequent input of the password. By pressing push button <SELECT/RESET>, LED I> lights up red. The output relays can now be assigned to this current element as tripping relays. By repeatedly pressing of the <SELECT/RESET> push button and assignment of the relays all elements can be assigned separately to the relays. The assignment mode can be terminated at any time by pressing the <SELECT/RESET> push button for some time (abt. Note: · The function of jumper J2 described in general description "MR Digital Multifunctional Relays" has no function. For relays without assignment mode this jumper is used for parameter setting of alarm relays (activation at pickup or tripping). · A form is attached to this description where the setting requested by the customer can be filled-in. This form is prepared for telefax transmission and can be used for your own reference as well as for telephone queries. Table 5. 2: Default settings of blocking functions Assignment of the output relays: Unit MRI1 has five output relays. The fifth output relay is provided as permanent alarm relay for self supervision is normally on. Output relays 1 - 4 are normally off and can be assigned as alarm or tripping relays to the current functions which can either be done by using the push buttons on the front plate or via serial interface RS485. The assignment of the output relays is similar to the setting of parameters, however, only in the assignment mode. By pressing push button <SELECT/RESET> in blocking mode again, the assignment mode is selected. TD_MRI1_06. 05_GB 21 Relay function 1 I> (V) tI> (V) I>> (R) tI> (R) I>> (V) tI>> (V) I>> (R) tI>> (R) IE> (V) tIE> (V) IE> (R) tIE> (R) IE>> (V) tIE>> (V) IE>> (R) tIE>> (R) tCBFP alarm tripping alarm tripping alarm tripping alarm tripping alarm tripping alarm tripping alarm tripping alarm tripping tripping X Output relays 2 3 X X 4 X X X X X X X X X X X X X Displayindication _2__ 1___ _2__ 1___ __3_ 1___ __3_ 1___ ___4 1___ ___4 1___ ___4 1___ ___4 1___ ____ Lighted LED I>; green tI>; green I>>; red tI>>; red I>E>; green tIE>>; green IE>>; red tI>>; red IE>; green tIE>; green IE>; red tIE>; red IE>>; green tIE>>; green IE>>; red tIE>>; red (V) = advance direction; (R) = reverse direction This way, a tripping relay can be set for each activation and tripping direction. Table 5. 3: Example of assignment matrix of the output relay (default settings). 22 TB MRI1 09. 00 E 5. 3 Setting value calculation 5. 4 Indication of measuring and fault values 5. 3. 1 Definite time overcurrent element 5. 4. 1 Indication of measuring values Low set element I> The pickup current setting is determined by the load capacity of the protected object and by the smallest fault current within the operating range. The pickup current is usually selected about 20% for power lines, about 50% for transformers and motors above the maximum expected load currents. The delay of the trip signal is selected with consideration to the demand on the selectivity according to system time grading and overload capacity of the protected object. High set element I>> The high set element is normally set to act for near-by faults. A very good protective reach can be achieved if the impedance of the protected object results in a well-defined fault current. In case of a line-transformer combination the setting values of the high set element can even be set for the fault inside the transformer. The time delay for high set element is always independent to the fault current. The following measuring quantities can be indicated on the display during normal service: · Apparent current in phase 1 (LED L1 green) · Active current in Phase 1 (LED L1 and IP green) * · Reactive current in Phase 1 (LED L1 and IQ green)* · Apparent current in phase 2 (LED L2 green) · Active current in Phase 2 (LED L2 and IP green) * · Reactive current in Phase 2 (LED L2 and IQ green)* · Apparent current in phase 3 (LED L3 green) · Active current in Phase 3 (LED L3 and IP green) * · Reactive current in Phase 3 (LED L3 and IQ green)* · Apparent earth current (LED E green) · Active earth current (LED E and IP green) * · Reactive earth current (LED E and IQ green) * · Residual voltage UR (LED UE) only at ER/XR-relay type · Angle between IE and UE * only in case that the directional option is built in. (For MRI1-XR/X relays the indicated measuring values refer to % of IN) 5. 3. 2 Inverse time overcurrent element Beside the selection of the time current characteristic one set value each for the phase current path and earth current path is adjusted. [. . . ] In actual service, for example, the measured current values on the MRI1 relay display may be compared phase by phase with the current indications of the ammeter of the switchboard to verify that the relay works and measures correctly. In case of a MRI1 relay with directional feature, the active and reactive parts of the measured currents may be checked and the actual power factor may be calculated and compared it with the cos -meter indication on the switchboard to verify that the relay is connected to the power system with the correct polarity. 6. 4. 10 Test of the CB failure protection For testing the tripping time a test current of about 2 times the rated current to be injected. The timer is started upon tripping of the relay of a protection function (I>, I>>, IE>, IE>>) and stopped as soon as the relay for the CB failure protection has picked up. The tripping time ascertained by the timer should not deviate more than 1% or, at short trip delay, less than 10 ms from the set tripping time. [. . . ]