Bourdon Tube Travel Stop Installation And Adjustment - Fisher 4195 KB Series Instruction Manual

4195KA, KB, and KC Series
11. For a controller with reset, adjust the reset adjust-
ment to 0.01 minutes per repeat. The rate adjustment
(4195KC) should remain in the OFF position.
12. The controller output should be within 2 psig (0.14
bar) of the supply pressure. If not, adjust flapper level-
ing screw 1 (the screw nearest the nozzle) until the
output is within 2 psig (0.14 bar) of supply pressure.
13. Remove the tape from the process pointer and
connect link 1 to the Bourdon tube.
14. Perform the controller calibration procedures and,
if necessary, the appropriate remote set point calibra-
tion procedure in section 3 or 4.
Bourdon Tube Travel Stop Installation
and Adjustment
The process indicator should be cali-
brated before installing or adjusting
travel stops. Refer to the appropriate
process indicator zero and span calibra-
tion procedure in section 3 or 4.
Refer to figure 5–18 for adjustment locations and fig-
ure 5–24 for key number locations.
The lower travel stop is necessary only if the operating
range lower limit is greater than 0 psig (elevated zero)
For example: The process scale limits may be 0 to
300 psig, but the range of operation is 150 to 300 psig.
In this example the elevated zero is 150 psig and the
lower travel stop would be adjusted for 5 percent of
the process scale span less than 150 psig
(150 – (0.05 X 300) = 135 psig).
1. Remove the two screws (key 6), and lift off the pro-
portional band indicator cover (key 36).
2. Set the proportional band between DIRECT and
REVERSE.
3. Install the upper travel stop (key 73) or upper and
lower travel stops (keys 73 and 74) with the machine
screws (keys 75 and 76). Do not tighten the machine
screws (key 75) that secure the upper travel stop. If
only the upper travel stop is installed, go to step 10.
Otherwise proceed with step 4.
4. If the operating range lower limit is 0 psig, and a
lower travel stop is installed, adjust the lower travel
stop adjustment so it does not interfere with the Bour-
don tube. Tighten the lower travel stop adjustment
lock nut and proceed to step 10. If the operating range
lower limit is other than 0 psig (elevated zero), perform
steps 5 through 15.
5–20
Note
LOWER TRAVEL STOP
ADJUSTMENT LOCK NUT
LOWER TRAVEL STOP
(KEY 74)
56A9752-U SHT 4
A6945 / IL
Figure 5–18. Bourdon Tube Controller Travel Stop Adjustment
5. If the process scale lower limit is other than 0 psig,
adjust the process pressure to 5 percent of the pro-
cess scale span less than the operating range lower
limit (see example at the beginning of this procedure).
6. Adjust the lower travel stop adjustment (shown in
figure 5–18) until it touches the Bourdon tube.
7. Tighten the lower travel stop adjustment lock nut.
8. Increase the process pressure to the operating
range lower limit.
9. The Bourdon tube should not touch the lower travel
stop. If it does, repeat steps 5 through 8.
10. Apply process pressure to the controller equal to
105 percent of the process scale span.
11. Slide the upper travel stop (key 73) until it touches
the Bourdon tube.
12. Tighten the machine screws (key 75).
13. Decrease the process pressure to 100 percent of
the process scale span.
14. The Bourdon tube should not touch the upper
travel stop. If it does, repeat steps 10 through 13.
15. Adjust the proportional band to 400 percent in the
desired action and install the proportional band indica-
tor cover (key 36). Tighten the two screws (key 6).
MOUNTING
SCREW
(KEY 76)
MOUNTING
SCREWS (KEY 75)
LOOSEN THESE
SCREWS TO
ADJUST
UPPER TRAVEL
STOP
MOUNTING
SCREW
(KEY 76)
UPPER
TRAVEL
STOP
(KEY 73)
LOWER TRAVEL
STOP ADJUSTMENT