ABB ACSM1 Series, Manual

Page: 383 / 510

Standard function blocks
383
FUNG-1V
(10072)
Illustration
Execution time 9.29 µs
Operation The output (Y) at the value of the input (X) is calculated with linear interpolation from
a piecewise linear function.
Y = Y
k
+ (X - X
k
)(Y
k+1
- Y
k
) / (X
k+1
- X
k
)
The piecewise linear function is defined by the X and Y vector tables (XTAB and YTAB).
For each X-value in the XTAB table, there is a corresponding Y-value in the YTAB table.
The values in XTAB and YTAB must be in ascending order (i.e. from low to high).
XTAB and YTAB values are defined with the DriveSPC tool.
The balancing function (BAL) permits the output signal to track an external reference
and gives a smooth return to the normal operation. If BAL is set to 1, output Y is set to
the value of the balance reference input (BALREF). The X value which corresponds to
this Y value is calculated with linear interpolation and it is indicated by the balance
reference output (BALREFO).
If the X input is outside the range defined by the XTAB table, the output Y is set to the
highest or lowest value in the YTAB table.
If BALREF is outside the range defined by the YTAB table when balancing is activated
(BAL: 0 -> 1), the output Y is set to the value of the BALREF input and the BALREFO
output is set to the highest or lowest value in the XTAB table.
The ERROR output is set to 1 when the number of the XTAB and YTAB inputs are
different. When ERROR is 1, the FUNG-1V block will not function. XTAB and YTAB
tables can be defined in the
DATA CONTAINER block (page 382 ) or the REG-G block
(page 389 ).
Inputs The input data type is selected by the user.
Balance input (BAL): Boolean
Balance reference input (BALREF): DINT, INT, REAL, REAL24.
X value input (X): DINT, INT, REAL, REAL24
X table input (XTAB): DINT, INT, REAL, REAL24
Y table input (YTAB): DINT, INT, REAL, REAL24
FUNG-1V
(DINT) 60
TLA1 1 msec (1)
BAL
BALREF
X
XTAB
YTAB
Y
Y(60)
BALREFO
BALREFO(60)
ERROR
ERROR(60)
X1 X2 X3 X4
Y1
Y2
Y3
Y4
X
Interpolated Y
X table
(XTAB) Y table
(YTAB)
X1 Y1
X2 Y2
X3 Y3
… …
X9 Y9