Rockwell Automation 2707-NP DTAM Programming Software - Manual (Page 31)

Chapter 3
Designing DTAM Plus and
DTAM Micro Applications
3–7
Scaling Formulas
The scaling formula for a DTAM display value is:
Displayed Value = m x Register Value + b
Where:
Display Maximum Value – Display Minimum Value
Register Maximum Value – Register Minimum Value
m =
Display Minimum Value – ( m x Register Minimum Value ) b =
The scaling formula for an entered valued is:
Register Value = m x Entered Value + b
Where:
Register Maximum Value – Register Minimum Value
m =
Register Minimum Value – ( m x Entry Minimum Value ) b =
Entry Maximum Value – Entry Minimum Value
Scaling example: Register Range = 0
! 4,095
Display Range = -100
! +300
Actual Register Value = 2,047
300 - (-100)
4,095 - 0
m =
-100 - (0.0977 x 0) = -100 b =
= 0.0977
Displayed Value = 0.0977 x 2,047 + (-100)
= 99.9919
= 100