Emerson Rosemount OCX 8800, Инструкция по эксплуатации

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Instruction Manual
IM-106-880C, OI
Section 5:
Calibration
April 2017
D/A Trim Procedures -
HART
77
5.7 D/A Trim Procedures - HART
5.7.1 O
2
D/A trim procedure using HART
Use the following procedure to perform the O
2
D/A trim procedure using the Field
Communicator. If necessary, refer to Section 6, 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. Select O2 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 O2 output.
5. Remove the electronics housing cover.
6. Refer to Figure 2-6 . 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 at the Field
Communicator.
7. The Field Communicator displays Setting Fld dev output to 4 mA. Press OK. Read the O
2
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
O
2
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.