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LOCKING
NUT
SCREW AND WASHER
(KEYS 19 AND 20)
NOTES:
1
SCREW INSERTED INTO THE ADJUSTABLE SET POINT PIVOT ASSEMBLY.
2
SCREW INSERTED INTO THE RELAY NOZZLE TUBING ASSEMBLY.
W4195 / IL
Figure 5-6. Adjustable Set Point Pivot Assembly
Locking Nut Location
firmly against the relay nozzle tubing assembly. With
the nozzle centered on the flapper, tighten the ma-
chine screw (key 19). Ensure that the nozzle is still
centered on the flapper.
27. Insert the pivot of the adjustable set point pivot
assembly (key 17) into the hole in the set point beam
assembly (key 23).
28. Insert the screw, with washer (keys 19 and 20),
through the frame (key 3) and start it into the adjust-
able set point pivot assembly (key 23), but do not
tighten.
29. Squeeze the adjustable set point pivot assembly
against the set point beam assembly. Check to be
sure the nozzle is still centered on the flapper and
tighten the machine screw (key 19). If necessary, loos-
en both machine screws (key 19) to allow slightly mov-
ing the adjustable set point pivot assembly, set point
beam assembly and the relay nozzle tubing assembly
as a unit to center the nozzle on the flapper. After cen-
tering the nozzle, tighten the two machine screws.
30. Turn the proportional band adjustment knob to 5
percent DIRECT. Refer to figure 5-6 to locate the lock-
ing nut on the adjustable set point pivot assembly.
Loosen the locking nut and back out the set screw
slightly so that the set point beam assembly falls un-
der its own weight when pivoted upward. Also, main-
tain a minimum side play between the adjustable set
point pivot assembly and the nozzle tubing assembly.
Tighten the locking nut.
31. At the frame manifold (key 135), tighten the nut
that secures the tubing from the relay nozzle tubing
ADJUSTABLE SET POINT
PIVOT ASSEMBLY
SCREW AND WASHER
2
(KEYS 19 AND 20)
1
4194A, B, and C Series
assembly (key 18). Apply full supply pressure with the
nozzle capped and check for leaks. Remove supply
pressure.
32. Install the set point beam bias spring (key 28) into
the frame bore and onto the spring seat on the set
point beam assembly.
33. Attach link 3 to the set point beam shoe as shown
in figure 5-3.
34. For controllers with reset or rate adjustment
(4194B or 4194C series), turn the reset adjustment to
the CLOSED (4194B) or OFF (4194C) position. Set
the rate adjustment to the OFF position.
The controller output must be 0 psig (0 bar). To be
sure the controller output is 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 (4194B) or OFF
(4194C) position.
35. Apply the correct supply pressure (refer to table
1-4) to the controller and provide an accurate means
of measuring the controller output pressure.
36. Perform the appropriate process indicator zero
and span calibration procedure and, if necessary, the
remote set point zero and span calibration procedure
in section 3 or 4. When calibration is complete, contin-
ue with step 37 below.
The following procedure (steps 37
through 43) matches the process point-
er motion to the set point indicator mo-
tion so the controller will control at set
point at all positions on the process
scale.
37. Set the proportional band to 40 percent RE-
VERSE or DIRECT depending on the desired control-
ler action.
38. Adjust the set point to the lower limit on the pro-
cess scale.
39. Disconnect link 1 from the input element, noting
the hole from which it is removed and tape the pro-
cess pointer to the lower limit on the process scale.
The output pressure may be anywhere between 3 and
15 psig (0.2 to 1.0 bar) for a 3 to 15 psig (0.2 to 1.0
bar) output signal range or between 6 and 30 psig (0.4
to 2.0 bar) for a 6 to 30 psig (0.4 to 2.0 bar) output
signal range. If the output is not within the specified
range, adjust the flapper leveling screw nearest the
nozzle until the output is within the range specified.
Record the output pressure.
40. Adjust the set point to the upper limit on the pro-
cess scale.
Note
5–9
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