ABB 266 Operating Instruction page 62

266 Models - FOUNDATION Fieldbus
If not, a configuration error shall be set in BLOCK_ERR and the actual mode of the block shall go to Out of Service. Write checks may
also be implemented, but they may force the order of entry of the x terms.
If the curve has m points, m<21, the non-configured points, [xm+1; ym+1], [xm+2; ym+2], ... [x21; y21] shall be set to +INFINITY to
mark them as unused. Since x1 is the smallest specified value for the input and xm is the largest, the output shall be at y1 when the
input is smaller than x1 and at ym when the input is larger than xm. Since the ends of the y curve act as limits, the OUT status shall
show when either limit is active.
Reversing path 2:
A reverse function swaps the interpretation of IN_2 and OUT_2, which provides a way to do back calculation using the same curve. If
the parameter SWAP_2 is set true, the block shall provide:
IN_1 = x and OUT_1 = y while IN_2 = y and OUT_2 = x
If the function is not monotonic in y and SWAP_2 is true, then BLOCK_ERR shall indicate a configuration error and the actual mode go
to Out of Service as above for x. A function is called monotonic when y values always increase or decrease when x values increase, e.g.
the function does not present peaks, valleys, or flat spots.
If SWAP_2 = false, IN_1 and IN_2 have the same engineering units defined in X_RANGE and OUT_1 and OUT_2 use the units defined in
Y_RANGE.
If SWAP_2 = true, OUT _1 and IN_2 have Y_RANGE and OUT_2 and IN_1 have X_RANGE.
Configuration hints
The minimum configuration for having the SC working and/or moving out from the OOS needs at least the following settings:
– Set SWAP_2 different by 0
– Set at least one X and Y pairs
– Set the X values monotonically increasing or the Y values monotonically increasing or decreasing
62 OI/266/FF/ADD-EN Rev. B | 2600T Series Pressure transmitters