Flowserve 3400IQ Digital Positioner - Manual (Page 61)

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Logix 3400IQ Digital Positioner FCD LGENIM3401-00 – 06/06
flowserve.com
4. Remove the plastic board cover by removing the three retaining screws (see Figure 16).
5. Remove the retaining screw from the main PCB assembly.
6. Remove the five wire connections from the main PCB assembly and lift the main PCB out of the
housing (see Figure 16).
7. Reinstall the five wire connections (see Figure 12) on the new main PCB.
8. Install the new main PCB into the housing. Insert the retaining screw through the board into the
threaded boss and tighten, using a Phillips screwdriver. Do not over tighten.
9. 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 (see Figure
16).
10. Reinstall all covers.
11. Reconnect power and air supply to the positioner and reconfigure the positioner being sure to
perform a stroke calibration.
8.8 Pressure Sensor Board
On advanced model Logix 3400IQ positioners, a pressure sensor board is installed in the positioner.
The pressure sensor board contains two pressure sensors that measure the pressure on output ports
1 and 2. 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 375 Handheld Communicator or Host
configuration software.
In the standard model, the pressure sensor board is replaced by a plate that plugs the actuator pres-
sure 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 11, 15 and 21 and proceed as outlined below.
The following tools are required:
• Phillips screwdriver
c 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).