Owner manual

Publication 1762-UM003A-EN-P - February 2003
Module Data, Status, and Channel Configuration 3-11
Figure 3.1 Linear Relationship Between Temperature and Proportional Counts
The value +32767 corresponds to the highest value for the device. For
example, if a 100Ω platinum 385 RTD is selected, the lowest
temperature of -200°C corresponds to -32768 counts. The highest
temperature of 850°C corresponds to +32767 counts. See Determining
Effective Resolution and Range on page 3-20.
Scaling Examples
+ 32,767
-32,768
850 ˚C
±200 ˚C
Counts
°C
EXAMPLE
Scaled-for-PID to Engineering Units x1
• input type = 200Ω Platinum RTD
•α = 0.00385°C
• range = -200 to +850°C S
LOW
= -200°C S
HIGH
= +850°C
• channel data = 3421(scaled-for-PID)
Engineering Units Equivalent = S
LOW
+ (S
HIGH
- S
LOW
) x (channel data/16383)]
Engineering Units Equivalent = -200°C + [(+850°C -(-200°C)) x (3421/16383)] =
19.25°C