4195KA, KB, KC, and KS Controllers
Instruction Manual
Form 5207
April 2007
3-6
Remote Set Point (suffix letter M) Zero
and Span Calibration
Refer to figures 3-1 and 3-3 for adjustment
locations. Refer to figure 7-1 for key number
locations.
Note
Any adjustment of the remote set
point span adjustment screw requires
readjustment of the remote set point
zero adjustment screw.
1. Remove the two screws (key 6) and lift off the
proportional band indicator cover (key 36).
2. Set the proportional band between DIRECT and
REVERSE.
3. Apply remote set point pressure equal to the
lower range limit.
4. The set point indicator should indicate the
process scale lower limit. If not, loosen the remote
set point zero adjustment locking screw and adjust
the remote set point zero adjustment screw until the
set point indicator aligns with the process scale
lower limit. Tighten the zero adjustment locking
screw.
5. Apply remote set point pressure equal to the
upper range limit.
6. The set point indicator should indicate the
process scale upper limit. If not, adjust the remote
set point span adjustment screw to correct one-half
the error as follows: clockwise to increase span for a
low indication; counterclockwise to decrease span
for a high indication.
7. Repeat steps 3 through 6 until the error is
eliminated.
8. Apply remote set point pressure equal to the
mid-range value.
9. Make sure the set point indicator is within ±1
percent of the mid-scale mark and if so, proceed to
step 12. If the set point indicator is not within 1
percent, but is within ±2 percent of the mid-scale
mark, then proceed with step 10. If the set point
indicator is not within ±2 percent, proceed to the
remote set point calibration procedure in the
Maintenance section.
10. Loosen the remote set point zero adjustment
locking screw and adjust the remote set point zero
adjustment screw to correct for half the error at
mid-scale. Tighten the zero adjustment locking
screw.
11. Apply remote set point pressure equal to the
lower and upper range limits and make sure the set
point indicator is within ±1 percent.
12. If necessary, perform the process indicator zero
and span calibration procedure in this section.
Otherwise, perform the flapper alignment procedure
in this section.
Flapper Alignment
Note
Perform the process indicator zero
and span calibration procedure and,
for controllers with remote set point
(suffix letter M), the remote set point
zero and span calibration procedure
before the flapper alignment.
Flapper leveling screw numbers and adjustments
are shown in figure 3-3. Key number locations are
shown in figure 7-1.
Provide a means of measuring the controller output
pressure by connecting the controller output to a
pressure gauge (open-loop conditions must exist).
Provide a regulated supply pressure to the
controller. Do not exceed the normal operating
pressure in table 1-6. After performing the flapper
alignment procedure, go to the startup procedure.
1. For a controller with manual set point, move the
set point indicator to the mid-scale mark on the
process scale. For a controller with remote set point
(suffix letter M), adjust the remote set point pressure
until the set point indicator is at the mid-scale mark
on the process scale.
2. Apply process pressure equal to the mid-scale
value of the process scale span. If pressure is not
available to pressure the input element to the
mid-scale value, an alternate method is to
disconnect link number 1 at the input element and
tape the process pointer at the mid-scale mark on
the process scale. If the controller has a capsular
input element, note the hole from which link number
1 was removed for proper replacement. This method
should only be used if pressure is not available to
pressure the input element to the mid-scale value.
3. Remove the two machine screws (key 6) and lift
off the proportional band indicator cover (key 36).
4. Adjust the proportional band between DIRECT
and REVERSE.
5. The controller output should be 0.62 ±0.007 bar
(9 ±0.10 psig) for a 0.2 to 1.0 bar (3 to 15 psig)
output or 1.2 ±0.01 bar (18 ±0.2 psig) for a 0.4 to 2.0
bar (6 to 30 psig) output. If not, adjust flapper
leveling screw 2 (the screw nearest the nozzle) until
the output is within tolerance.
6. Set the proportional band to 30 percent DIRECT.
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