Emerson Rosemount 3490 Series, Справочное руководство

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Figure 4-12: Transmitter Input Channel 1 for HART Input
B
P111
D900
A
D901
D902
D903
PV, SV,
TV or FV
P112
C
P114
D
(SV)
D801
(TV)
D802
(FV)
D803
SV, TV and FV
H
D800 E
P113
Scaled
P
ro
fil
es
F G
(PV)
I
P117
SV
P115 P116
TV
FV
D851
(CH1 O/P)
P111 = “Tx1 : PV”
J
P210
A. Txr HART Variables
B. Input Source Select
C. Apply Input Offset
D. Apply Input Scale
E. Profile Select
F. Non-Linear Profile
G. Post Scale NLP
H. Low Cut-off Check
I. Output Map
J. PV Damping
Optional damping of control unit PV ten times a second: D800 = [D800
((D800now - D800before)/(1+10
× P210))]
HART digital data is continuously read from the transmitter
The HART transmitter digitally communicates pre-calculated values of four HART variables
Primary Variable (PV), Secondary Variable (SV), Tertiary Variable (TV), and Fourth Variable
(FV) to the Rosemount 3490 Series Control Unit.
Selection of a HART variable as source for further processing
Parameter P111 selects one of the four HART variables (PV, SV, TV, or FV) on the
transmitter to be the source for further processing to get a result from Input Channel 1.
The unselected HART variables are mapped to control unit D80x parameters (see
Figure
4-12 ).
Note
In Figure 4-12 , the selected source is the HART Primary Variable (PV). Alternatively,
Tx1:
SV , Tx1: TV , or Tx1: FV can be selected.
Read-only parameters D80* are in the menu MONITOR
→
READINGS .
Applying the optional offset adjustment to the selected source
Parameter P112 is a positive, negative, or zero offset for adjustment of the selected HART
variable. As an example, this feature may be used to handle a standing level in a tank.
Note
P112 is in the menu:
SETUP
→
CONTROLLER
→
INPUT CHANNEL
→
Ch1 I/P Offset (on 3491/3) or SETUP
→
CONTROLLER
→
PV CALCULATION
→
CHANNEL 1
→
Ch1 I/P Offset
(on 3492)
Reference Manual Getting started
00809-0100-4841 January 2021
Emerson.com/Rosemount 67