ABB RELION REX640 - 5.1.5 Operation principle

See the preprocessing function blocks in this document for the possible
signal sources.
Improper analog channel configuration causes a validation error if the analog
channels are not completely configured or they do not match with certain settings.
For troubleshooting, check the contents of this chapter and also the preprocessing
blocks in this document. The configuration can be written to the protection relay
once the mismatch is corrected.
5.1.5 Operation principle
The function can be enabled and disabled with the
Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of INRPHAR can be described using a module diagram. All the
modules in the diagram are explained in the next sections.
BLOCK
t
Timer
BLK2H
I_2H_B /
I_1H_B
I_2H_A /
I_1H_A
I_2H_C /
I_1H_C
Level
detector
t
Timer
AND
t
Timer
AND
I3P
I_1H_A
I_1H_B
I_1H_C
I_2H_A
I_2H_B
I_2H_C
AND
Phase
selection
logic
I_1H_A
I_1H_B
I_1H_C
Figure 657: Functional module diagram
I_2H/I_1H
These modules calculate the ratio of the second harmonic (I_2H) and fundamental
frequency (I_1H) of the phase currents. The calculated value is compared to the set
Start value . If the calculated value exceeds the set Start value , the module output is
activated.
Level detector
The output of the phase-specific level detector is activated when the fundamental
frequency current I_1H exceeds the set Min operate current of the nominal current.
Timer
Once activated, Timer runs until the set Operate delay time value is exceeded. The
time characteristics is according to DT. When the operation timer has reached the
Operate delay time value, the Timer module output is activated. If the timer has
Protection related functions
1MRS759142 F
1158 REX640
Technical Manual