Calculate the equivalent Process Variable for any given percentage of signal ( 0 to 100%). We need Transmitter Span, Lower Range Value and Upper Range Value.
Percentage to Process Variable Conversion
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Formula:
Process Variable = Span(X/100) +LRV
Span = (URV) – (LRV)
Where
X is Percentage of signal
URV is Upper Range of value
LRV is Lower range of value
Example:
A pressure gauge is ranged -1 to 1 bar; calculate the Measured Variable for 40 % of signal
Span = (URV) – (LRV) = 2 Bar
Process Variable = Span(X/100) +LRV
Process Variable = (2)(40/100)+(-1)
Process Variable = -0.2 Bar
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