Emerson Rosemount 6888A, Reference Manual

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The thermal pad (F) will most likely remain attached to the mounting plate.
5. Disconnect the two wire harness connectors from the back of the transmitter board
and remove the plastic cover and transmitter board.
Replacement transmitter boards come in two configurations:
a. Transmitter board with thermal pad and mounting screws
b. Transmitter board, thermal pad, plastic cover, mounting plate, and mounting
screws
6. If only the transmitter board is being replaced, carefully unsnap the plastic cover
from the old transmitter board and then snap it onto the new board.
The cover goes in one way only with the screw terminals for the power and signal
wiring fitting into the openings in the cover.
If the transmitter board, plastic cover, and mounting plate are being replaced, the
plastic cover should already be snapped onto the transmitter board.
7. Remove the old thermal pad from the mounting plate. Attach the new thermal pad
to the mounting plate 1 in. up from the flat edge of the pad.
Do not reassemble without the thermal pad in place. If the transmitter board, plastic
cover, and mounting plate are being replaced, the thermal pad should already be in
place on the mounting plate.
8. If the mounting pad is being replaced, remove the four screws (H) securing the plate
to the housing. Install the new mounting plate using four screws.
Replacement screws are provided if any become lost or damaged.
9. Reconnect the two wire harness connectors to the back of the transmitter board.
The connectors are different and individually keyed to prevent misconnection.
10. Carefully push the wire harnesses through the hole in the mounting plate and align
the transmitter board with plastic cover over the three standoffs on the mounting
plate.
11. Install the three screws to secure the board to the mounting plate.
Replacement screws are provided if any become lost or damaged.
12. Reconnect the power and signal wires to the transmitter board.
13. Reinstall the cover to the transmitter housing.
14. Reapply power to the transmitter. Prior to using the transmitter for measurement
purposes, perform one of the following:
• Transmitter without Rosemount 6888Xi: Recalibrate the transmitter. See
Chapter 3 .
• Transmitter with Rosemount 6888Xi: When initialization is complete, the
transmitter begins to heat up, but an alarm condition is shown on the
Rosemount 6888Xi. Synchronize the calibration parameters via the Rosemount
6888Xi as follows:
a. Press DIAG once to view the alarms. A
Probe Changed
alarm appears.
b. Press EXIT once to enter the Diagnostic menu.
Maintenance and service
Reference Manual 101