Terminal Board Assembly Removal And Replacement; Non-Field-Replaceable Items - Siemens 7MF4033 series User Manual

Calibration and Maintenance

7.4.4 Terminal Board Assembly Removal and Replacement

Perform this procedure to replace the terminal board assembly. The terminal board assembly usually can
be replaced at the installation site; if not, remove the transmitter for bench servicing.
Removal
1. Use the proper procedures to shut down the process.
2. Remove power from the transmitter and remove the enclosure cap at the "Field Terminals" end of the
enclosure to access the terminal board.
3. Retrieve the wrist strap from the maintenance kit and snap it on your wrist. Connect the ground clip
to the transmitter ground screw.
4. Mark and then disconnect the loop wiring using a medium-size Phillips blade screwdriver, disconnect
the wiring.
5. Remove two terminal board mounting screws and external tooth lockwashers.
6. Pull the terminal board straight out of the compartment.
7. Discard the defective board.
Installation
1. Retrieve the wrist strap from the maintenance kit and snap it on your wrist. Connect the ground clip
to the transmitter ground screw.
2. Remove the replacement terminal board assembly from its packaging.
3. Note the two long feed-thru pins in the transmitter enclosure. These two pins must enter two
receptacles on the circuit board side of the terminal board assembly. Carefully align the two mounting
holes in the terminal board with the threaded holes in the enclosure casting and gently press the
terminal board into place until it seats inside the enclosure. Do not use excessive force; do not bend
the two long feed-thru pins!
4. Insert two terminal board mounting screws and lockwashers and tighten to 12 in-lbs (1.4 Nm).
5. Connect loop wiring.
6. Install the enclosure cap by turning it clockwise until the O-ring contacts the enclosure. Turn the cap
one additional turn to compress the O-ring.
7. As necessary, reinstall the transmitter in the field.
8. Restore power to the transmitter. Calibration is not required.

7.5 NON-FIELD-REPLACEABLE ITEMS

Certain components are not replaceable except at the factory. These are:
•
Enclosure cap display
viewing glass:
•
RFI feed-thrus
7-16
Agency regulations do not permit field replacement of a broken or
damaged glass as this would invalidate the enclosure's explosion proof
rating. Replace the entire damaged enclosure cap assembly.
Potted
UMSITRPSD3-1
November 2005