Emerson Process Management 3051N User Manual
Reference Manual
00809-0100-4808, Rev CA
June 2008
June 2008
2-19
Rosemount 3051N
Recall Factory Trim
The Recall Factory Trim commands allow the restoration of the as-shipped
factory settings of the sensor trim and analog output trim.
factory settings of the sensor trim and analog output trim.
Recall Factory Trim—
Sensor Trim
Sensor Trim
Resets the transmitter sensor trim to the as-shipped factory settings. The
Recall Factory Trim—Sensor Trim command can be useful for recovering
from an inadvertent zero trim of an absolute pressure unit.
Recall Factory Trim—Sensor Trim command can be useful for recovering
from an inadvertent zero trim of an absolute pressure unit.
Recall Factory Trim—
Analog Output
Analog Output
Resets the transmitter analog output trim to the as-shipped
factory settings. The Recall Factory Trim—Analog Output Trim command can
be useful for recovering from an inadvertent zero trim on an absolute pressure
transmitter.
factory settings. The Recall Factory Trim—Analog Output Trim command can
be useful for recovering from an inadvertent zero trim on an absolute pressure
transmitter.
Analog Output Trim
The Analog Output Trim commands allow you to adjust the transmitter’s
current output at the 4 and 20 mA points to match the plant standards. This
command adjusts the digital to analog signal conversion (see Figure 2-7).
current output at the 4 and 20 mA points to match the plant standards. This
command adjusts the digital to analog signal conversion (see Figure 2-7).
Digital-to-Analog Trim
To perform a digital-to-analog trim with a HART Communicator, perform the
following procedure.
following procedure.
1.
From the
ONLINE
screen, select 1 Device setup, 2 Diag/Service,
3 Calibration, 2 Trim Analog Output, 1 Digital-to-Analog Trim. Select
OK
after you set the control loop to manual (see “Setting the Loop to
2.
Connect an accurate reference ammeter to the transmitter at the
CONNECT REFERENCE METER
prompt. To do so, connect the
positive lead to the positive terminal and the negative lead to the test
terminal in the transmitter terminal compartment, or shunt the
transmitter power through the reference meter at some point.
terminal in the transmitter terminal compartment, or shunt the
transmitter power through the reference meter at some point.
3.
Select
OK
after connecting the reference meter.
4.
Select
OK
at the
SETTING FLD DEV OUTPUT TO 4 MA
prompt. The
transmitter outputs 4.00 mA.
5.
Record the actual value from the reference meter, and enter it at the
ENTER METER VALUE
prompt. The communicator prompts you to
verify whether or not the output value equals the value on the
reference meter.
reference meter.
6.
Select 1 Yes if the reference meter value equals the transmitter
output value, or 2 No if it does not.
output value, or 2 No if it does not.
IF you select 1 Yes, THEN proceed to Step 7.
IF you select 2 No, THEN repeat Step 5.
7.
Select
OK
at the
SETTING FLD DEV OUTPUT TO 20 MA
prompt,
and repeat Steps 5 and 6 until the reference meter value equals the
transmitter output value.
transmitter output value.
8.
Select
OK
after you return the control loop to automatic control.
Digital-to-Analog Trim
Using Other Scale
Using Other Scale
The Scaled D/A Trim command matches the 4 and 20 mA points to a
user-selectable reference scale other than 4 and 20 mA (1 to 5 volts if
measuring across a 250 ohm load, or 0 to 100 percent if measuring from a
DCS, for example). To perform a scaled D/A trim, connect an accurate
reference meter to the transmitter and trim the output signal to scale as
outlined in the Output Trim procedure.
user-selectable reference scale other than 4 and 20 mA (1 to 5 volts if
measuring across a 250 ohm load, or 0 to 100 percent if measuring from a
DCS, for example). To perform a scaled D/A trim, connect an accurate
reference meter to the transmitter and trim the output signal to scale as
outlined in the Output Trim procedure.
HART Comm.
1, 2, 3, 4, 1
HART Comm.
1, 2, 3, 4, 2
HART Comm.
1, 2, 3, 2, 1
HART Comm.
1, 2, 3, 2, 2