ABB RELION REX640, Technical Manual, Page: 304 / 1960

3.22.6 Real not equal comparator NER
3.22.6.1 Function block
Figure 178: Function block
3.22.6.2 Functionality
The real not equal comparator function NER compares the real input
REAL_IN1
with
the real input
REAL_IN2
and activates the binary output
OUT
if
REAL_IN1
is outside
the region of
REAL_INT2
+
TOLR
and
REAL_IN2
-
TOLR
. That is, if
REAL_IN1
<
(
REAL_IN2
-
TOLR
) or
REAL_IN1
> (
REAL_IN2
+
TOLR
),
OUT
= 1, else
OUT
= 0.
If inputs
REAL_IN1
or
REAL_IN2
are outside the range, then
OUT
is set to 0.
Not equal region
RTOLR
REAL_IN2-TOLR
REAL_IN2
Max 2097151.000
Min -2097152.000
Not equal region
Figure 179: Region of NER comparison
NER requires a positive value for
TOLR
, otherwise it may not function
properly. The
TOLR
value can be set using SETRGAPC.
NER function blocks do not have the hysteresis feature. Oscillating
outputs should be avoided when comparing analog signals that have
closely varying values.
Basic functions 1MRS759142 F
304 REX640
Technical Manual