ABB RELION REX640 Technical Manual page 173

1MRS759142 C
REX640
Technical Manual
Value maximum and Value minimum affect the scaled output range. The range of the
scaled input is defined with the settings Input minimum and Input maximum.
Depending on setting Num of knee points, the output can be scaled with up to five
linear curves. The knee points are defined by parameters Input knee point 1-4 and
Value knee point 1-4.
Example 1: VMMXU1 to mA output
VMMXU1
U3P HIGH_ALARM
BLOCK HIGH_WARNING
LOW_WARN
LOW_ALARM
U12-kV
U23-kV
U31-kV
U_INST_A
U_INST_B
U_INST_C
GUID-7FFF850A-E041-41F3-9CF9-1A72C49E83E7 V1 EN
Figure 58: Application example for VMMXU1 to mA output
The measured phase-to-phase voltage from VMMXU is connected to AO_VAL. Input
maximum value is set to "24" (kV) and Input minimum value is set to "18" (kV). The
input unit is not significant as long as the value range is in the same scale. Value
maximum is set to "20" mA and Value minimum to "4" mA. Num of knee points is set to
"0".
Output [mA]
Value maximum 20
12
Value minimum 4
18
Input minimum
GUID-B7597C96-9B41-475C-AD3F-AA1E98252966 V1 EN
Figure 59: Scaling of AO_VAL to mA output
Slot# – mA#
AO_VAL AI_VAL
HIGH_ALARM
HIGH_WARN
LOW_WARN
LOW_ALARM
21
Section 3
Basic functions
AO_VAL
24
Input maximum
167