Emerson Fisher 4194HA Instruction Manual page 66

4194HA, HB, HC Controllers
July 2018
2. For a controller with manual set point, move the set point adjustment to 50 percent of the scale range. For a
controller with remote set point, adjust the remote set point pressure until the set point indicator is at 50 percent of
the scale range.
3. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36).
4. Adjust the reset adjustment to 0.01 minute per repeat.
5. If the controller has rate (4194HC controllers), turn the rate adjustment to OFF.
6. If the controller has the external feedback option (available with 4194HB controllers only), shut off the supply
pressure, connect the controller output to the external feedback connection, and turn on the supply pressure. See
figure 2‐2 for the location of the output and external feedback connections.
7. Adjust the process differential pressure to 50 percent of the input range. If pressure is not available to pressure the
differential pressure unit to 50 percent of range, an alternate method is to disconnect link 1 at the drive arm and
tape the process indicator at 50 percent of the input range. This method should only be used if pressure is not
available to pressure the differential pressure unit to 50 percent.
Note
In steps 8 through 12, the controller output will not stabilize because of the high controller gain. The controller output gauge is
adequate to check the output pressure during this procedure.
8. Set the proportional band between DIRECT and REVERSE.
9. Adjust flapper leveling screw number 2 until the controller output is relatively stable at any value within the output
range.
10. Adjust the proportional band to 20 percent DIRECT (direct action). Adjust flapper leveling screw number 3 until the
controller output is relatively stable at any value within the output range.
11. Adjust the proportional band to 20 percent REVERSE (reverse action). Adjust flapper leveling screw number 1 until
the controller output is relatively stable at any value within the output range.
12. Repeat steps 8 through 11 until the controller output remains relatively stable with no adjustments of the flapper
leveling screws.
Note
Steps 13 through 19 check the flapper alignment.
13. Adjust the proportional band to 100 percent DIRECT (direct action).
14. Apply pressure to the differential pressure unit or, if link 1 was disconnected, remove the tape from the process
indicator and move the indicator until it aligns with the right‐hand edge of the set point indicator (as shown in
figure 5‐1).
Controller output should be within 0.14 bar (2 psig) of the supply pressure.
15. Pressure the differential pressure unit or, if disconnected, move the process indicator to the left‐hand edge of the
set point indicator (as shown in figure 5‐1).
Controller output pressure should go to 0 psig.
16. Adjust the proportional band to 100 percent REVERSE (reverse action).
17. Pressure the differential pressure unit or, if disconnected, move the process indicator to align with the right‐hand
edge of the set point indicator. The controller output should be 0 psig.
66
Instruction Manual
D200156X012