Woodward
Manual MRIK3-C EN
68
DOK-TD-MRIK3-C Rev. A
7.4.5
Test circuit for MRIK3 relay with earth-current directional
recognition (ER/XR models)
Figure 7.2: Test circuit
For testing relays MRIK3-ICER/XR with earth fault directional feature, current and voltage input
signals with adjustable phase shifting are required. Figure 7.2 shows an example of a single phase
test circuit with adjustable voltage and current energizing the MRIK3 relay under test.
For testing a relay with earth fault directional feature, one of the input energizing quantity (voltage)
shall be applied to the relay with a constant value within its effective range. The other input energiz-
ing quantity (current) and phase angle shall be appropriately varied.
With the aid of phase angle indicated on the display the correct function of the relay MRIK3-
ICER/XR can be checked (ER-relay type).
Parameters I
E>
and I
E>>
should be set to EXIT.
The following measured values are shown:
Measured value
LED
Earth current
E, I
E>
Active share
E, I
P
reactive share
E, I
Q
Earth voltage
E, U
E>
Angel E,
I
E>
, U
E>
