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2. Loosen the screw in the replacement link B and
adjust the length to match the link being replaced.
Tighten the screw.
3. Refer to figure 5–23 for the correct link orientation.
Attach the replacement link B to the pivot arm and to
the set point indicator in the same holes as noted in
step 1.
4. Perform the remote set point maintenance calibra-
tion procedure. Perform the appropriate process indi-
cator zero and span calibration and flapper alignment
procedures in section 3 or 4.
Remote Set Point (suffix letter M)
Maintenance Calibration
Refer to figure 5–23 for parts and adjustment loca-
tions. Refer to figures 5–24 and 5–30 for key number
locations.
Precalibration Procedure
1. Remove the two screws (key 6) and lift off the pro-
portional band indicator cover (key 36).
2. Set the proportional band adjustment between DI-
RECT and REVERSE.
3. Remove the two screws (key 103) and remove the
tie bar (key 106) from the remote set point assembly.
Aligning the Flexures
1. Apply remote set point pressure equal to 50 per-
cent of the remote set point pressure range.
2. The guide flexure (key 119) should be straight and
horizontal. If not, straighten the flexure by loosening
the machine screw (key 122) on the end of the flexure
that is attached to the top of the pivot assembly A (key
114) and allow the flexure to straighten itself. Tighten
the machine screw.
3. If the flexure is not horizontal, loosen the two ma-
chine screws (key 139) and raise or lower the pedestal
assembly (key 105) until the guide flexure is horizon-
tal. Retighten the machine screws (key 139) and en-
sure the diaphragm assembly extension (key 134) is
centered in the upper travel stop (key 83) hole.
4. The drive flexure (key 79) should be straight. If not,
proceed as follows:
a. Loosen the screw (key 118) on the adjustment
arm of pivot assembly A (key 114) and loosen the
screws holding the drive flexure.
b. Set the length of the adjustment arm so that the
drive flexure is parallel to the centerline of the dia-
phragm capsule assembly (key 80).
4195KA, KB, and KC Series
c. Tighten the screw (key 118) on the adjustment
arm.
See figure 5–20. The adjustment arm of
the remote set point pivot assembly A
turns on a bushing at each end of the
shaft supporting the adjustment arm. In
the next step, position the shaft so both
bushings ''float'' inside the bearings
and do not rest against the end of either
bearing.
d. Hold the pivot assembly A shaft in the middle of
the bushing end play. Be sure neither bushing is
resting against the inside end of either bearing.
e. Tighten the screws that hold the drive flexure in
place.
Setting the Travel Stops
1. Loosen the set screw (key 87) in the travel stop nut
(key 86).
Make sure the loose travel stop nut does
not bind on the diaphragm capsule ex-
tension (key 134) when pressurizing the
capsules (key 80). Damage to the cap-
sules may result.
2. Full span stop—Adjust the remote set point pres-
sure to 2-1/2 percent of span greater than the remote
set point input range upper limit.
Loosen the two screws (keys 139 and 140) that se-
cure the travel stop (key 83) to the mounting plate (key
111). Slide the travel stop until it is just touching the
end of the capsule stack. Tighten the travel stop
mounting screws to lock it into position.
3. Zero Stop—Adjust the remote set point pressure
to 2-1/2 percent of span less than the remote set point
input range lower limit.
Slide the travel stop nut (key 86), along the diaphragm
capsule extension (key 134) until it is just touching the
travel stop (key 83). Tighten the set screw (key 87) to
lock the travel stop nut in position.
Aligning the Linkage
1. Adjust the remote set point pressure to 50 percent
of the remote set point input range.
2. Set the linearity adjustment screw in the center of
the slot on the lever arm of pivot clevis assembly B
(key 115). See figure 5–23 for the linearity adjustment
location.
Note
Note
5–33
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