ABB RELION REX640 Technical Manual page 1353

1MRS759142 C
REX640
Technical Manual
making the number negative, the remaining bits are identical to those of the coded
positive number.
The tap position validity is set to good in all valid cases. The quality is set to bad in
invalid combinations in the binary inputs. For example, when the "BCD2INT" mode
is selected and the input binary combination is "0001101", the quality is set to bad. For
negative values, when the SIGN_BIT is set to TRUE (1) and the input binary
combination is "1011011", the quality is set to bad.
If the tap changer has auxiliary contacts for indicating the extreme positions of the tap
changer, their status can be connected to END_POS_R and END_POS_L inputs. The
END_POS_R (End position raise or highest allowed tap position reached) status refers
to the extreme position that results in the highest number of the taps in the tap changer.
Similarly, END_POS_L (End position lower or lowest allowed tap position reached)
status refers to the extreme position that results in the lowest number of the taps in the
tap changer. TAP_POS output is dedicated for transferring the validated tap position
for the functions that need tap position information, for example OLATCC and
TRxPTDF. It includes both the actual position information and the status of reached
end positions, assuming that inputs END_POS_R and END_POS_L are connected.
Table 1293: Truth table of the decoding modes
Inputs
SIGN_ BI5 BI4
BIT
... ...
1 0 0
1 0 0
1 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
Table continues on next page
BI3 BI2 BI1
...
0 0 1
0 0 1
0 0 0
0 0 0
0 0 0
0 0 1
0 0 1
0 1 0
0 1 0
0 1 1
0 1 1
1 0 0
1 0 0
1 0 1
1 0 1
1 1 0
1 1 0
1 1 1
1 1 1
Section 8
Measurement functions
TAP_POS outputs
BI0 NAT2I BCD2I
NT NT
... ... ...
1 -3 -3
0 -2 -2
1 -1 -1
0 0 0
1 1 1
0 2 2
1 3 3
0 4 4
1 5 5
0 6 6
1 7 7
0 8 8
1 9 9
0 10 9
1 11 9
0 12 9
1 13 9
0 14 9
1 15 9
GRAY2
INT
...
-2
-3
-1
0
1
3
2
7
6
4
5
15
14
12
13
8
9
11
10
1347