Emerson Rosemount 3051S Reference Manual page 44

Rosemount 3051S ERS System
Module Assignments
Fast Keys
3-12
Strapping Table Method
Scaled Variable can also be configured by inputting a traditional "level vs.
volume" strapping table. The steps for using the Strapping Table method are
described below:
1. Select the unit of measure that the Level data will be inputted.
2. Enter in a text string (up to 5 characters: A-Z, -, %, /, *, and "space") to
define the unit of measure for the volume data. Examples include
GALNS or LITER.
3. Define the specific gravity of the process fluid.
4. Define the number of strapping table points that will be inputted.
5. Enter the first Level value (in engineering units) and the corresponding
Volume value.
6. Repeat Step 5 for the number of strapping table points defined in Step 4.
7. A Scaled Variable configuration will automatically be generated based on
the provided strapping table information. Verify and modify the Scaled
Variable configuration if necessary.
8. To have the 4-20 mA signal of the ERS system output the Scaled
Variable measurement, map Scaled Variable to the HART Primary
Variable and configure the Upper and Lower Range Values.
The ERS system calculates DP by taking the pressure measurement from the
P transmitter and subtracting the pressure measurement from the P
2, 2, 6 HI
transmitter.
ERS transmitters are shipped from the factory preconfigured such that the
primary sensor (4-20 loop termination and optional LCD) is assigned as the
P device, and the secondary sensor (junction box housing) is assigned as
HI
the P device. In installations where the primary transmitter is installed on
LO
the P process connection (such as at the top of a tank), these designations
LO
may be switched electronically using a Field communicator.
Changing the P
1. View the neck label on each ERS transmitter and note the serial number
and pressure location (P
2. Using a Field communicator, view the serial number and the assigned
pressure location for either "Module 1" or "Module 2."
3. If the currently assigned P
installation as recorded from Step 1, change the P
using either of the following commands:
•
Set Module 1 = P
• Set Module 1 = P
View the DP measurement from the ERS system and verify the calculation is
of positive magnitude. If the DP measurement is of negative magnitude, use
the other Module Assignment command from Step 3.
and P Module Assignments
HI LO
vs. P ) of the transmitter.
HI LO
/ P designations do not reflect the actual
HI LO
, Module 2 = P
HI
, Module 2 = P
LO
Reference Manual
00809-0100-4804, Rev AA
January 2011
/ P assignments
HI LO
LO
HI
LO