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4194A, B, and C Series
b. To decrease the span further than the adjust-
ment screw allows, move both ends of link A (key
116) to the left.
c. Make fine adjustments with the remote set point
span adjustment screw.
8. Repeat the adjustments until the upper and lower
indications are aligned with the upper and lower limits
on the process scale.
9. Adjust the remote set point pressure for 50 percent
of the remote set point input range.
10. The set point indicator should indicate mid-scale
2 percent of the process scale span. If the error is
within 2 percent, proceed to step 11. If the error is
greater than 2 percent of the scale span, proceed to
the remote set point linearity adjustment procedure.
11. Adjust the set point indicator to mid-scale 1 per-
cent of the process scale span by loosening the zero
adjustment locking screw and turning the zero adjust-
ment screw. Tighten the locking screw.
12. Adjust the remote set point pressure to the upper
and lower limits of the remote set point input range
and make sure the set point indicator is still within 1
percent of the lower and upper limits of the process
scale.
13. Perform the appropriate flapper alignment proce-
dure and, if necessary, the process indicator zero and
span calibration procedure in section 3 or 4.
Remote Set Point Linearity Adjustment
Adjust the linearity by loosening and repositioning the
linearity adjustment screw in the curved slot on the
lever arm of pivot assembly B (key 115). Adjusting the
linearity affects the zero and span adjustment.
1. Adjust the remote set point pressure to 50 percent
of the remote set point input range. The set point indi-
cator should indicate mid-scale 1 percent of the pro-
cess scale span. If not, make fine adjustments by
loosening the zero adjustment locking screw and turn-
ing the zero adjustment screw.
2. Adjust the remote set point pressure to 0 percent of
the remote set point input range and note the indicator
position relative to the process scale lower limit.
3. Adjust the remote set point pressure to 100 percent
of the remote set point input range and note the indi-
cator position relative to the process scale upper limit.
4. If the greatest misalignment is positive (the set
point indicator is to the right of the process scale lim-
its), loosen the linearity screw and move it clockwise in
the slot. If the misalignment is negative, move the lin-
earity screw counterclockwise in the slot.
5. If misalignment is greater than 1 percent of the pro-
cess scale span at the lower and upper limits, with one
5–30
positive and the other negative, perform the remote
set point zero and span adjustment procedure to cor-
rect a span error.
6. Repeat steps 1 through 4 until lower, middle, and
upper indications are within 1 percent of the process
scale markings.
Auto/Manual Station (suffix letter E)
Maintenance
Replacing the Auto/Manual Station
Refer to figures 5-21 and 5-27 for key number loca-
tions.
This procedure also permits replace-
ment of the switch manifold O-rings
(key 312), the auto/manual tubing as-
sembly (key 138), and the frame gaskets
(keys 4 and 5).
Disassembly
1. Remove the controller assembly from the case by
performing steps 1 through 3 of the case and cover
replacement procedures.
2. Loosen the screw (key 316) that holds the auto/
manual station (key 273) to the controller frame.
3. Loosen the two screws (key 314 and 315) that hold
the auto/manual station to the auto/manual tubing as-
sembly (key 138).
4. Remove the auto/manual station from the controller
frame.
5. Remove the switch manifold O-rings (key 312).
6. Carefully loosen the nut on the relay nozzle tubing
assembly (key 18) where it connects to the auto/
manual tubing assembly (key 138). Loosen three
screws (keys 34 and 131), and remove the tubing as-
sembly and frame gaskets (keys 4 and 5).
7. Inspect the gaskets (keys 4 and 5) and O-rings
(key 312) for wear. Replace if necessary.
Assembly
8. Install the gaskets and the tubing assembly to the
frame. Start, but do not tighten, the three screws (keys
34 and 131) and the nut on the nozzle tubing assem-
bly (key 18).
9. Install the switch manifold O-rings (key 312), and
secure the auto/manual station to the controller frame
with the screw (key 316) and to the tubing assembly
(key 138) with two screws (keys 314 and 315). Do not
tighten any screws.
CAUTION
In the next step, take care to tighten the
two screws (keys 314 and 315) evenly.
Note
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