PCX: All Editions
New Feature: Square Root Breakpoint
Some flow transmitters are set up to react in a Linear fashion at the lowest part of their range to prevent outsized reactions near zero.
Default: 0.0 %
At 0% the entire range reacts with a Square Root response at any value in the range. E.g.
25% of Input Range correlates to 50% of Output Range
16% of Input Range correlates to 40% of Output Range
1.25% of Input Range correlates to around 11.18% of Output Range
1.0% of Input Range correlates to around 10% of Output Range
0.64% of Input Range correlates to around 8% of Output Range
0.01% of Input Range correlates to 1% of Output Range
0% of Input Range correlates to 0% of Output range.
Common: 0.9%, 1.0%
For many common Flow transmitters, the lowest non-zero portions of the flow react linearly. This breakpoint allows for one logical step where test points <= the Breakpoint % are treated as Linear and the balance of the range is treated as square root. In a scenario where the breakpoint is 1.0%:
25% of Input Range correlates to 50% of Output Range
16% of Input Range correlates to 40% of Output Range
1.25% of Input Range correlates to around 11.18% of Output Range
*1.0% of Input Range correlates to 1.0% of Output Range
*0.64% of Input Range correlates to 0.64% of Output Range
*0.01% of Input Range correlates to 0.01% of Output Range
*0% of Input Range correlates to 0% of Output range.
Note the points indicated with * above are at or below the breakpoint, so they react in a linear fashion.
This helps with values very close to zero from having incorrect expected reactions in square root flow transmitters, which is commonly pre-programmed into leading documenting process calibrators.