Proportional counts to engineering units, Engineering units to proportional counts – Rockwell Automation 1746-NT4 Series B,D17466.6.1 SLC 500 4-Channel Thermocouple/mV Input Module User Manual User Manual
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Publication 1746-UM007C-EN-P - July 2004
5-8 Channel Configuration, Data, and Status
Proportional Counts to Engineering Units
Equation: Engr Units Equivalent = SLOW + { (SHIGH - SLOW)
x [ ( Proportional Counts value displayed + 32768) / 65536 ] }
•
Assume type E input type, proportional counts display type,
channel data = 21567.
•
Want to calculate °F equivalent.
•
From Channel Data Word Format table, SLOW = -454°F and
SHIGH = 1832°F.
Solution: Engr Units Equivalent = -454°F + { [1832°F - (-454°F) ]
x [ ( 21567 + 32768) / 65536 ] } = 1441.3°F
Engineering Units to Proportional Counts
Equation: Proportional Counts Equivalent = { 65536 x [ ( Engineering
Units desired - SLOW ) / ( SHIGH - SLOW ) ] } - 32768
•
Assume type E input type, proportional counts display type,
desired channel temp. = 1000°F.
•
Want to calculate Proportional Counts equivalent.
•
From Channel Data Word Format table, SLOW = -454°F and
SHIGH = 1832°F.
Solution: Proportional Counts Equivalent = { 65536 x [ ( 1000°F -
(-454°F) ) / (1832°F - (-454°F ) ) ] } - 32768 = 8916.