IDEC FL1E SmartRelay - Manual (Page 140)

IDEC SmartRelay functions
126 IDEC SmartRelay Manual 
Mathematical rule
Actual value Ax = 
(internal value at input Ax • gain) + offset
Gain and offset calculation
The gain and offset is calculated based on the relevant high
and low values of the function.
Example 1:
The available thermocouples have the following technical
data: -30 to +70 C, 0 to 10 V DC (i.e. 0 to 1000 in IDEC
SmartRelay).
Actual value = (internal value • gain) + offset, thus
-30
= (0 • A) + B, i.e. offset B = -30
+70 = (1000 • A) -30, i.e. gain A = 0.1
Example 2:
A pressure sensor converts a pressure of 1000 mbar into a
voltage of 0 V, and a pressure of 5000 mbar into a voltage of
10 V.
Actual value = (internal value • gain) + offset, thus
1000
= (0 • A) + B, i.e. offset B = 1000
5000 = (1000 • A) +1000, i.e. gain A = 4