Rerange; Rerange With A Communicator Only - Emerson Rosemount 3051N Reference Manual

Reference Manual
00809-0100-4808, Rev CA
June 2008
FIGURE 2-5. Square Root
Output Transition Point.
Full Scale Output
(mA dc)

Rerange

Rerange with a
Communicator Only
HART Comm. 1, 2, 3, 1, 1
Full Scale
Flow (%)
Sq. Root Curve
Transition
Point
Slope=42
Slope=1
The Range Values command sets the 4 and 20 mA points (lower and upper
range values). Setting the range values to the limits of expected readings
maximizes transmitter performance. In practice, you may reset the transmitter
range values as often as necessary to reflect changing process conditions.
You may use one of three methods to rerange the transmitter. Each method is
unique; examine all three closely before deciding which method to use.
Reranging using only the communicator changes the values of the analog 4
and 20 mA points independently without a pressure input.
NOTE
Changing the lower or upper range point results in similar changes to the
span.
To rerange using only the communicator, enter the fast-key sequence above,
select 1 Keypad input, and follow the on-line instructions. Or enter the values
directly from the ONLINE screen.
Rosemount 3051N
Sq. Root
Curve
Transition Point
Linear Section
2-9