Emerson Rosemount OCX8800A - Page 223

Potential cause
Electronics package failure.
Recommended action
Replace electronics package.
9.3.9 O2 TC Open
Oxygen sensor heater thermocouple open.
Potential cause
O
2
thermocouple or thermocouple circuit open.
Recommended actions
1. Check O
2
thermocouple and circuit wires for breaks or loose
connections per Figure 9-2 and Figure 10-8.
2. Repair breaks or loose connections or replace failed thermocouple.
3. Perform procedure in Reset to continue operation.
9.3.10 COe TC Open
Combustibles sensor heater thermocouple open.
Potential cause
Combustibles sensor thermocouple open.
Recommended actions
1. Check thermocouple resistance (lead to ground) of reference and active
thermocouples per Figure 9-2 and Figure 10-10.
2. If either thermocouple is open or shorted to ground, replace
combustibles sensor.
9.3.11
SB TC Open
Sample block heater thermocouple open.
Potential cause
Sample block heater thermocouple or thermocouple circuit open.
Recommended actions
1. Check sample block thermocouple and circuit wires for breaks or loose
connections per Figure 9-2 and Figure 10-8.
2. Repair breaks or loose connections or replace failed thermocouple.
3. Perform Reset to continue operation.
Manual
Troubleshoot
00809-0500-4880 December 2022
Rosemount OCX8800A 223