Analog Channel Configuration - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.2.4.4
454
The measured admittance is compared to the admittance characteristic boundaries in
the admittance plane. The supported characteristics include overadmittance,
oversusceptance, overconductance or any combination of the three. The directionality
of the oversusceptance and overconductance criteria can be defined as forward,
reverse or non-directional, and the boundary lines can be tilted if required by the
application. This allows the optimization of the shape of the admittance characteristics
for any given application.
EFPADM supports two calculation algorithms for admittance. The admittance
calculation can be set to include or exclude the prefault zero-sequence values of Io and
Uo. Furthermore, the calculated admittance is recorded at the time of the trip and it can
be monitored for post-fault analysis purposes.
To ensure the security of the protection, the admittance calculation is supervised by a
residual overvoltage condition which releases the admittance protection during a fault
condition. Alternatively, the release signal can be provided by an external binary
signal.
The function contains a blocking functionality. It is possible to block function outputs,
timers or the function itself.

Analog channel configuration

EFPADM has two analog group inputs which must be properly configured.
Table 510: Analog inputs
Input
IRES
URES
See the preprocessing function blocks in this document for the
possible signal sources.
There are a few special conditions which must be noted with the configuration.
Table 511: Special conditions
Condition
URES calculated
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.
Description
Residual current (measured or calculated)
Residual voltage (measured or calculated)
Description
The function requires that all three voltage
channels are connected. Setting
must be "Wye" in that particular UTVTR.
1MRS759142 C
VT connection
REX640
Technical Manual