Emerson Rosemount OCX8800A - D;A Trim Procedures

5.5 D/A trim procedures
5.5.1 O
2
D/A trim using HART
®
Refer to the HART menu tree, Figure 5-3.
Note
To select a menu item, either use Up and Down to scroll to the menu item and
press Right or use the number keypad to select the menu item number.
To return to a preceding menu, press Left.
Procedure
1. From the DIAG/SERVICE menu, select D/A TRIM.
The Field Communicator displays O2 D/A Trim.
2. Press Right to start the procedure.
If you wish to exit the D/A Trim with no changes, select ABORT.
The Field Communicator displays: WARNING: Loop should be removed
from automatic control.
3. Remove the transmitter from any automatic control loops to avoid a
potentially dangerous operating condtion and press OK.
The Field Communicator displays Connect reference meter to O2 output.
4. Remove the electronics housing cover.
5. Connect a digital multimeter to read the milliamp output from the O
2
D/A
converter circuit. Connect the positive lead to the AOUT1+ terminal and
connect the negative lead to the AOUT1- terminal. Then press OK on the
Field Communicator.
Refer to Figure 2-4, Figure 2-5, and Figure 2-6.
The Field Communicator displays Setting Fld dev output to 4 mA.
6. Press OK. Read the O
2
miliamp output at the digital multimeter. Enter the
reading at the Field Communicator and press ENTER.
Select ABORT to exit without changes.
The Field Communicator displays Setting Fld dev output to 20 mA.
7. Press OK. Read the O
2
miliamp output at the digital multimeter. Enter the
reading at the Field Communicator and press ENTER.
Select ABORT to exit without changes.
The Field Communicator displays Setting Fld dev output to 4 mA.
8. Press OK.
The Field Communicator displays Fld dev output 4.00 mA equal to
reference meter?
9. Using Up or Down, select 1 Yes or 2 No and press ENTER.
If No, the process repeats from Step 5.
The Field Communicator displays Setting Fld dev output to 20 mA.
10. Press OK.
Manual Using HART
®
communications
00809-0500-4880 December 2022
Rosemount OCX8800A 89