SMC Networks ISA3 Series Operation Manual page 95

○Conversion formula of the process data and display value
(1) Conversion formula from the process data to the display value: Disp = a x PD + b
(2) Conversion formula from the display value to the process data: PD = (Disp – b) / a
Disp: Product display value and set value
PD: Process data measurement value
a: Inclination
b: Intercept
[Inclination and intercept according to the product type]
Type Inclination a
ISA3-F
ISA3-G
ISA3-H
[Inclination and intercept to the unit specification]
Unit Inclination a
kPa
bar
psi
[Calculation example]
(1) Conversion formula from the process data to the display value (process value)
(Units specification: kPa, PD = 1000)
Disp = a x PD + b
= 0.1 x 1000 + 0
= 100.0[kPa]
(2) Conversion formula from the display value (pressure value) to the process data
(Units specification: kPa, Disp = 120.0[kPa])
PD = (Disp – b) / a
= (120.0 – 0) / 0.1
= 1200
Intercept b
0.02 0
0.1 0
0.2 0
Intercept b
0.1 0
0.001 0
0.014504 0
-94-
4 How to use
No.PS※※-OMW0009-A