Emerson FISHER FIELDVUE DLC3010 Instruction Manual page 74

DLC3010 Digital Level Controller
Service Tools
May 2018
TV is the value of Tertiary Variable. The TV is either the Temperature measured by an RTD located in the process
fluid, or the user-entered Process Temperature (if the Process Temperature Source setting is Manual Entry).
Analog Output indicates the current value for the analog output of the instrument being commanded by the
firmware, in milliamperes.
% Range indicates the current process variable in percent of span determined by the lower range value and the
upper range value.
Refer to figure 5‐1. If the digital level controller is setup for direct action the lower range value is less than the upper
range value. If the digital level controller is setup for reverse action the lower range value is greater than the upper
range value. Use the following equation to calculate the % Range values:
PV(%range) +
where:
PV = process variable in engineering units
EU
The LRV always represents the 0% range value and the URV always represents the 100% range value.
Note
In the DLC3010 the % Range signal that is reported via HART signalling is back-calculated from the Analog Output signal (instead
of the Analog Output being calculated from the % Range). Therefore, the % Range value reported in the HART interface will reflect
analog output saturation limits, fixed current mode, and alarm current values. However, the % Range value reported on the
instrument LCD is derived correctly and stays linear out to the sensor limits.
Figure 5‐1. PV % Range Indication for Direct and Reverse Action with a 32‐Inch Displacer Ranged for 8 to 24 Inches
150
130
110
90
70
50
30
10
–10
–30
–50
0 4 8
LRV
DIRECT ACTION
E0383
D Compensation—System gains that are adjusted for process temperature when table data and temperature source
are available.
74
* LRV)
(PV
EU
100
(URV * LRV)
12 16 20 24 28
URV
LEVEL (INCHES)
150
130
110
90
70
50
30
10
–10
–30
–50
32
0 4
URV
Instruction Manual
8 12 16 20 24
LRV
LEVEL (INCHES)
REVERSE ACTION
D102748X012
28 32