2
TD_MRI1_06.05_GB
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 (t
I>
)
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 (t
I>>
)
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 U
E
(ER/XR-relay
type)
5.2.10 Pickup current for earth fault element (I
E>
)
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
(t
IE>>
)
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 (I
E>>
)
5.2.16 Trip delay for high set element of earth
fault supervision (t
IE>>
)
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 t
CBFP
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 testing and commissioning
6.1 Power-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
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
