Emerson Rosemount 5081FG, Reference Manual

Page: 80 / 105

Reference Manual
00809-0100-4882, Rev AB
May 2019
Rosemount 5081FG
6-4
Probe replacement may be conducted online as long as the process in which
the probe is mounted is operating at a negative, or slightly positive, pressure.
Refer to Section 5: Troubleshooting for more information.
Refer to Table 7-1 for replacement probe part numbers. Before replacing the
probe, verify that the reference air and calibration check gas lines are turned
off and disconnected from the probe.
1. Remove the end cap of the probe to expose the terminal block.
2. Refer to Figure 6-2. Disconnect the four wires (two oxygen signal wires
and two thermocouple wires) from the terminal block.
3. Disconnect the reference air and the calibration check gas lines.
4. Unscrew the probe from the stack and remove.
5. Using a replacement probe, refer to Mechanical Installation in Section 2:
Installation for mechanical installation instructions.
6. Refer to Electrical Installation in Section 2: Installation for electrical
installation instructions.
7. Refer to Pneumatic Installation in Section 2: Installation for reference air
and calibration check gas installation instructions.
Use heat resistant gloves and clothing when removing the probe. The probe can be as hot
as 1600
°
C (2912
°
F). This can cause severe burns.
Do not install or remove probes from a process where pressures are more than a few
inches of H
2
O positive pressure. Hot gases may escape from the stack and cause severe
personal injury.
Do not insert or withdraw a probe into or out of a hot process faster than 1 in. (25,4 mm) per
minute or instrument damage from thermal shock may occur.
Also, ash, slag, or other materials can build up on the probe body in some applications. If
this buildup is causing difficulty when withdrawing the probe, DO NOT FORCE. Rotate the
probe back and forth to attempt to loosen the material on the probe body. Or, wait until the
process cools down and access the buildup from inside the furnace.