Rosemount 4600, Reference Manual

Page: 51 / 68

Reference Manual
00809-0100-4022, Rev AA
July 2002
4-9
Model 4600
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 4-1 on
page 4-3).
Digital-to-Analog Trim
HART Communicator
To perform a digital-to-analog trim with a HART Communicator, perform the
following procedure.
1. From the
Home
screen, enter the fast key sequence shown. Select OK
after setting the control loop to manual, see “Setting the Loop to Manual”
on page 3-2.
2. Connect an accurate reference ammeter to the transmitter at the
Connect Reference Meter
prompt. Connect in series with the signal
loop, or shunt 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 4.0 mA.
5. Record the actual value from the reference meter, and enter it at the
Enter Meter Value
prompt. The HART Communicator prompts you to
verify whether or not the output value equals the value on the reference
meter.
6. Select 1: Yes, if the reference meter value equals the transmitter output
value, or 2: No if it does not.
a. If 1 is selected: Yes, proceed to Step 7.
b. If 2 is selected: No, 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.
8. Select
OK
after the control loop is returned to automatic control.
Fast Keys
1, 2, 3, 2, 1