Rockwell Automation 1746-NT4 Series B,D17466.6.1 SLC 500 4-Channel Thermocouple/mV Input Module User Manual - Manual (Page 59)

Publication 1746-UM007C-EN-P - July 2004
Channel Configuration, Data, and Status 5-7
Scaling Examples
Scaled-for-PID to Engineering Units
Equation: Engr Units Equivalent = SLOW + [ (SHIGH - SLOW) x
(Scaled-for-PID value displayed / 16384) ]
•
Assume type J input type, scaled-for-PID display type, channel
data = 3421.
•
Want to calculate °C equivalent.
•
From Channel Data Word Format table, SLOW = -210°C and
SHIGH = 760°C.
Solution: Engr Units Equivalent = -210°C + [ (760°C - (-210°C) ) x
(3421 / 16384) ] = -7.46°C.
Engineering Units to Scaled-for-PID
Equation: Scaled-for-PID Equivalent = 16384 x [ (Engineering Units
desired - SLOW) / ( SHIGH - SLOW ) ]
•
Assume type J input type, scaled-for-PID display type, desired
channel temp. = 344°C.
•
Want to calculate Scaled-for-PID equivalent.
•
From Channel Data Word Format table, SLOW = -210°C and
SHIGH = 760°C.
Solution: Scaled-for-PID Equivalent = 16384 x [ (344°C - (-210°C) )
/ ( 760°C - (-210°C ) ) ] = 9357.