Logix 3400MD Digital Positioner FCD LGENIM3404-00 – 9/09
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calibrated. The actuator pressure sensor calibration is performed using
a 375 Handheld Communicator or Host configuration software.
In the standard model, the pressure sensor board is replaced by a
plate that plugs the actuator pressure sensor ports. This plate can be
replaced by a pressure sensor board to field-upgrade a standard model
to an advanced model.
Removing the Pressure Sensor Board (Advanced Model)
To replace the pressure sensor board, refer to Figures 12, 16 and 21
and proceed as outlined below. The following tools are required:
• Phillips screwdriver
0
WARNING:
Observe precautions for handling electrostatically
sensitive devices.
1. Make sure the valve is bypassed or in a safe condition.
2. Disconnect the power and air supply to the unit.
3. Remove the main cover.
4. Remove the plastic board cover by removing the three retaining
screws (see Figure 16).
5. Disconnect the ribbon cable on the pressure sensor board from the
PCB assembly (see Figure 12). Lifting the main board may make
this easier.
6. Remove the two screws holding the pressure sensor board to the
housing. Lift the metal stiffener plate off the pressure sensor board
and set aside for future use.
7. Remove the pressure sensor board.
Removing the Pressure Sensor Plug Plate (Standard Model)
To upgrade a standard model to an advanced model, the pressure
sensor plug plate must be removed and replaced by a pressure sensor
board. The main PCB electronics automatically senses the presence of
the pressure sensor board. If present, the actuator pressure sensors
are used in the positioner control algorithm to enhance valve stability.
For optimal performance, the actuator pressure sensors need to be
calibrated. The actuator pressure sensor calibration is performed using
a Handheld Communicator or host configuration software. To upgrade
a standard model to an advanced model, refer to Figures 12, 16 and 21
and proceed as outlined below. The following tools are required:
• Phillips screwdriver
1. Make sure the valve is bypassed or in a safe condition.
2. Disconnect the power and air supply to the unit.
3. Remove the main cover.
4. Remove the plastic board cover by removing the three retaining
screws (see Figure 16).
5. Remove the two screws holding the pressure sensor plug plate to
the housing. Lift the metal stiffener plate off the pressure sensor
plug plate and set aside for future use.
6. Remove the pressure sensor plug plate and discard.
Installing the Pressure Sensor Board (Advanced Model)
The pressure sensor board is installed on the advanced model only. To
install the pressure sensor board, refer to Figures 12, 16 and 22 and
proceed as outlined below. The following tools are required:
• Phillips screwdriver
• Torque wrench
0
WARNING:
Observe precautions for handling electrostatic
sensitive devices.
1. Verify that the two pressure sensor O-rings (item 15) are in place in
the housing.
2. Set the pressure sensor board assembly in place so that the O-rings
make contact with the faces of the pressure sensors.
3. Place the metal stiffener plate (item 12) on top of the pressure
sensor board over the pressure sensors and align the two holes in
the pressure sensor plate with the threaded bosses in the housing.
4. Insert two screws through the stiffener plate and pressure sensor
board into the threaded holes in the housing and tighten evenly, to 8
in-lb.
5. Connect the ribbon cable on the pressure sensor board to the main
PCB assembly.
6. Install the plastic board cover. Insert the three retaining screws
through the plastic cover into the threaded boss and tighten evenly,
using a Phillips screwdriver. Do not overtighten.
7. Reinstall all covers.
8. Reconnect power and air supply to the positioner. Use the Host
software or a handheld communicator to perform a pressure
sensor calibration.
8.9 User Interface Board
The user interface board provides a connection point inside the
explosion-proof housing for all hookups to the positioner.
Replacing the User Interface Board
To replace the user interface board, refer to Figures 6, 12, 16 and 22
and proceed as outlined below. The following tools are required:
• Phillips screwdriver