Fisher 4195 KB Series Instruction Manual page 52

CLINCH
NUT
W4191-1 / IL
Figure 5–16. Flapper leveling Screw and Clinch Nut
seat on the set point beam assembly as shown in fig-
ure 5–3.
6. Move the set point indicator to the mid-scale mark
on the process scale.
7. Apply process pressure to position the process
pointer at the mid-scale mark on the process scale.
8. Adjust the proportional band to 5 percent DIRECT.
Turn flapper leveling screw 3 (the screw nearest the
nozzle) until the nozzle just touches the flapper.
9. Adjust the proportional band to 5 percent RE-
VERSE. Turn flapper leveling screw 1 (the screw
nearest the nozzle) until the nozzle just touches the
flapper.
10. Flapper leveling screws 1 and 3 should protrude
the same distance from the clinch nuts. A clinch nut is
shown in figure 5–16.
11. If leveling screw 1 protrudes further than leveling
screw 3, turn the link 3 adjusting screw counterclock-
wise. If leveling screw 3 protrudes further than leveling
screw 1, turn the link 3 adjusting screw clockwise.
12. Repeat steps 8 through 11 until leveling screws 1
and 3 protrude an equal distance from the clinch nuts.
13. Perform the controller calibration procedures and,
if necessary, the appropriate remote set point calibra-
tion procedure in section 3 or 4.
Replacing Bourdon Tube Controller Link 4
1. Remove the two screws (key 6), and lift off the pro-
portional band indicator cover (key 36).
2. Disconnect link 4 from the bellows bracket (key 31)
and the flapper assembly (key 11).
FLAPPER LEVELING
SCREW
4195KA, KB, and KC Series
BELLOWS BRACKET
(KEY 31)
W4195 / IL
Figure 5–17. Position of Link 4 Adjustment Screws
3. Connect the replacement link to the flapper assem-
bly so that the two adjusting screws on the link are
nearest to the bellows bracket (key 31) and so that the
screw heads are facing the bottom of the controller as
shown in figure 5–17.
4. For controllers with reset (4195KB Series) or reset
and rate adjustments (4195KC Series), turn the reset
adjustment to the CLOSED (4195KB) or OFF
(4195KC) position. Turn the rate adjustment (4195KC
Series) to the OFF position.
The controller output must be 0 psig (0 bar). To be
sure the controller output is at 0 psig (0 bar), remove
supply pressure, set the reset adjustment to 0.01 min-
utes per repeat and wait 30 seconds; then, turn the
reset adjustment to the CLOSED (4195KB) or OFF
(4195KC) position.
5. Adjust the proportional band to 5 percent RE-
VERSE and move the set point indicator to the pro-
cess scale upper limit.
6. Disconnect link 1 from the Bourdon tube and move
the process pointer to the process scale lower limit.
Tape the process pointer in this position.
7. Apply the correct supply pressure to the controller.
The output of the controller should be within 2 psig
(0.14 bar) of the supply pressure. If not, adjust flapper
leveling screw 1 (the screw nearest the nozzle) until
the output is within 2 psig (0.14 bar) of supply pres-
sure.
8. Loosen the two adjusting screws on link 4. Connect
the free end of the link to the bellows bracket and al-
low the link to find its free length.
9. Tighten the two adjusting screws on the link.
10. Raise link 4 out of the hole in the bellows bracket
(key 31) and ensure that it drops back into the hole
under its own weight. If not, repeat steps 8 and 9.
LINK 4 ADJUSTMENT
SCREW HEADS
5–19