Direct Or Reverse Action; Operating Information; Initial Considerations - Emerson Fisher 4200 Instruction Manual

4200 Transmitters
March 2011
4. Stroke the actuator or other device to the mid‐stroke position.
Note
On units with position switches, the (R) terminal on TB3 must be connected to the power supply negative (-) terminal as shown in
figure 9 to attain correct potentiometer alignment.
5. Apply power to the instrument.
6. While the device is in mid‐stroke position, insert a screwdriver blade into the slot in the end of the potentiometer
shaft (see figure 15), or turn the coupler (key 52, figure 19 or key 100E, figures 22 and 23) to turn the
potentiometer shaft until the DVM reads 1.25 ±0.05 volts DC. This establishes the electrical center of the
potentiometer.
7. Tighten the appropriate set screw. Check that the DVM reading has remained at 1.25 ±0.05 volts DC.
Note
For sliding‐stem applications, tighten the set screw (key 26, figure 15) in the operating arm (key 30) to a torque of 3.39 to 3.95
NSm (30 to 35 lbfSin).
8. Remove the power from the transmitter power supply.
9. Remove the DVM leads from TP3 and TP4 (transmitter signal) or TP5 and TP6 (position switch signal).
10. Refer to the direct or reverse action procedures.

Direct or Reverse Action

Direct action means, when looking at the slotted end of the potentiometer shaft, a clockwise rotation of the shaft
produces an increasing output signal from the transmitter.
Reverse action means, when looking at the slotted end of the potentiometer shaft, a clockwise rotation of the shaft
produces a decreasing output signal from the transmitter.
The transmitter produces a direct or reverse action output signal depending on the location of the potentiometer
wires inserted in terminal block number 1 (TB1) mounted on the transmitter printed wiring board. Refer to figure 6 for
the location of the wires and the wire color sequence for direct action.
For reverse action, exchange the positions of the brown and red wires.
Arrange wires on the terminal block (TB1) for either direct or reverse action to match the application requirements;
then repeat the potentiometer alignment procedures.
Refer to the Calibration section to adjust the zero and span of the transmitter and/or position switch circuits.

Operating Information

Initial Considerations

If the transmitter is ordered with an actuator, the transmitter is factory calibrated to the length of travel specified on
the order. If the transmitter is ordered separately, adjust the zero and span as described in the Calibration section so
that the transmitter operates properly in your specific application.
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Instruction Manual
D200354X012