ABB RELION REX640 Technical Manual page 174

Section 3
Basic functions
168
Example 2: mA input to mA output
Slot# – mA1
AO_VAL AI_VAL
HIGH_ALARM
HIGH_WARN
LOW_WARN
LOW_ALARM
Slot# – mA2
AO_VAL AI_VAL
HIGH_ALARM
HIGH_WARN
LOW_WARN
LOW_ALARM
GUID-7EDEF43D-037C-4A3C-A0E2-5624BABBC8E0 V1 EN
Figure 60: Application example for mA input to mA output
mA current is measured at channel 1. AI_VAL from measuring channel 1 is connected
to AO_VAL of output channel 2. Input maximum is set to "20" (mA) and Input
minimum to "-20" (mA). Value maximum is set to "20" mA and Value minimum is set
to "0" mA. Num of knee points is set to "2".
Output [mA]
Value maximum 20
Value knee
15
point 2
Value knee
5
point 1
Value minimum 0
-20
GUID-5B335082-F274-4327-AB79-874F22309EDF V1 EN
Figure 61: Scaling of AO_VAL to mA output with two knee points
Example 3: RTD input to mA output
Tap position is measured by the RTD channel 7. AI_VAL from channel 7 is connected
to AO_VAL of channel 1. Input maximum is set to "160" (ohm) and Input minimum to
"10" (ohm). Value maximum is set to "20" mA and Value minimum is set to "4" mA.
Num of knee points is set to "4".
-15
1MRS759142 C
AO_VAL
15 20
REX640
Technical Manual