Fisher 4194B Series Instruction Manual page 29

SET POINT
INDICATOR
PROCESS POINTER
REMOTE SET POINT
CONNECTED HERE
INPUT ELEMENT
CONNECTED HERE
CONNECTING
LINK
BEAM
SUPPLY PRESSURE
OUTPUT PRESSURE
NOZZLE PRESSURE
RESET PRESSURE
PROPORTIONAL PRESSURE
46A9764-B
C0593-3 / IL
termined value. Anti-reset windup reduces overshoot
of the process differential pressure that can result from
large or prolonged deviation from set point.
Remote Set Point (suffix letter M)
Operation
The capability to adjust the controller set point from a
remote location is available with all 4194B and C Se-
ries controllers. This option is designated by the suffix
letter M in the type number.
RESET BELLOWS
PROPORTIONAL
BELLOWS
FLAPPER
NOZZLE
TO
PROPORTIONAL
BELLOWS
DIFFERENTIAL
RELIEF VALVE
Figure 4-6. 4194C Series Controller Schematic
4194A, B, and C Series
PROPORTIONAL
BAND ADJUSTMENT
SUPPLY
PRESSURE
RATE VALVE
RESET VALVE
TO
RESET
TO-
BELLOWS
NOZZLE
RATE VALVE
RESET VALVE
A control pressure is applied to the capsular element
within the remote set point assembly. The expansion
and contraction of the capsule moves the set point
indicator via connecting linkage. Increasing the control
pressure to the capsule increases the set point setting
and decreasing the control pressure reduces the set
point setting.
Auto/Manual Station (suffix letter E)
Operation
A controller with the auto/manual station (designated
by the suffix letter E in the type number) has piping on
REVERSE ACTION
QUANDRANT
FEEDBACK
LINK
FEEDBACK
MOTION
DIRECT ACTION
QUADRANT
INPUT MOTION
OUTPUT PRESSURE
TO FINAL CONTROL
ELEMENT
RELAY
OUTPUT
RELAY
SUPPLY
PRESSURE
FLAPPER
PIVOT
4–11