Fisher 4194A Series, Инструкция по эксплуатации

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4194A, B, and C Series
4–7
2. If necessary, remove the two machine screws (key
6) and lift off the proportional band indicator cover (key
36).
3. Provide regulated supply pressure to the controller.
Do not exceed the normal operating pressure in table
1-4.
4. For a controller with manual set point, move the set
point indicator to the mid-scale mark of the process
scale span. For a controller with remote set point (suf-
fix letter M), adjust the remote set point pressure until
the set point indicator is at mid-scale mark of the pro-
cess scale.
5. Set the reset adjustment to 0.01 minutes per re-
peat.
6. If the controller has rate (4194C Series), turn the
rate adjustment to OFF.
7. Apply process differential pressure equal to the
mid-scale value of the process scale span. If pressure
is not available to pressure the input element to the
mid-scale value, an alternate method is to disconnect
link number 1 at the input element and tape the pro-
cess pointer at mid-scale mark on the process scale.
Note the hole where link number 1 is connected to the
input element, then disconnect link 1. This method
should only be used if pressure is not available to
pressure the input element to the mid-scale value.
Note
Because of the high controller gain, the
controller output will not remain stable
in steps 8 through 12. The controller
output gauge is adequate to check the
output pressure during this procedure.
8. Set the proportional band between DIRECT and
REVERSE.
9. The controller output should be relatively stable at
any value within the output range. If not, adjust flapper
leveling screw 2 (the screw nearest the nozzle) until
the output is relatively stable.
10. Set the proportional band to 30 percent DIRECT.
The controller output should be relatively stable at any
value within the output range. If not, adjust flapper lev-
eling screw 3 (the screw nearest the nozzle) until the
output is relatively stable.
11. Set the proportional band to 30 percent RE-
VERSE. The controller output should be relatively
stable within the output range. If not, adjust flapper
leveling screw 1 (the screw nearest the nozzle) until
the output is relatively stable.
12. Repeat steps 8 through 11 until the controller out-
put remains relatively stable without further flapper
leveling screw adjustment.
Figure 4-4. Alignment of the Process Pointer with the Set
Point Indicator
W4039-1 / IL
W4038-1 / IL
Note
Steps 13 through 19 check the flapper
alignment.
13. Set the proportional band to 30 percent DIRECT.
14. Apply process differential pressure to the input
element or, if link 1 was disconnected, remove the
tape from the process pointer and move the pointer
until it aligns with the right-hand edge of the set point
indicator as shown in figure 4-4.
The controller output should be within 2 psig (0.14 bar)
of the supply pressure.
15. Apply process differential pressure to the input
element or, if disconnected, move the process pointer
until it aligns with the left-hand edge of the set point
indicator as shown in figure 4-4.
The controller output pressure should go to 0 psig.
16. Set the proportional band to 30 percent RE-
VERSE.
17. Apply process differential pressure to the input
element or, if disconnected, move the process pointer
until it aligns with the right-hand edge of the set point
indicator as shown in figure 4-4. The controller output
should be 0 psig.
18. Apply process differential pressure to the input
element or, if disconnected, move the process pointer
until it aligns with the left-hand edge of the set point
indicator as shown in figure 4-4. The controller output
should be within 2 psig (0.14 bar) of the supply pres-
sure.