Emerson Rosemount OCX 8800, Instruction Manual

Page: 103 / 306

Section 5:
Calibration
April 2017
Instruction Manual
IM-106-880C, OI
78
COe D/A trim procedure using
HART
5.7.2 COe D/A trim procedure using HART
Use the following procedure to perform the COe D/A trim procedure using the Field
Communicator. If necessary, refer to
Section 6, Field Communicator , Field Communicator,
for the HART menu tree.
NOTE:
To select a menu item, either use the up and down arrow keys to scroll to the menu item and
press the right arrow key or use the number keypad to select the menu item number.
To return to a preceding menu, press the left arrow key.
1. From the DIAG/SERVICE menu, select D/A TRIM. Press the up or down arrow to select COe D/A
Trim.
2. Press the right arrow key to start the procedure. (If you wish to exit D/A Trim with no
changes, select ABORT.)
3. The Field Communicator displays WARNING: Loop should be removed from automatic
control. Remove the Hazardous Area OCX 8800 from any automatic control loops to
avoid a potentially dangerous operating condition and press OK.
4. The Field Communicator displays Connect reference meter to Combustibles output.
5. Remove the electronics housing cover.
6. Refer to Figure 2-6 . Connect a digital multimeter to read the milliamp output from the
COe D/A converter circuit. Connect the positive lead to the AOUT2+ terminal and
connect the negative lead to the AOUT2- terminal. Then, press OK at the HART
communicator.
7. The Field Communicator displays Setting Fld dev output to 4 mA. Press OK. Read the
COe milliamp output at the digital multimeter. Enter the reading at the Field
Communicator and press ENTER. (Select ABORT to exit without changes).
8. The Field Communicator displays Setting Fld dev output to 20 mA. Press OK. Read the
COe milliamp output at the digital multimeter. Enter the reading at the Field
Communicator and press ENTER. (Select ABORT to exit without changes).
9. The Field Communicator displays Setting Fld dev output to 4 mA. Press OK.
10. The Field Communicator displays Fld dev output 4.00 mA equal to reference meter?
Using the up or down arrow, select 1 Yes or 2 No and Press ENTER. If No, the process
repeats from step 6.
11. The Field Communicator displays Setting Fld dev output to 20 mA. Press OK.
12. The Field Communicator displays Fld dev output 20.00 mA equal to reference meter?
Using the up or down arrow, select 1 Yes or 2 No and Press ENTER. If No, the process
repeats from step 7.
13. The Field Communicator displays NOTE: Loop may be returned to automatic control.