Instruction Manual
D200156X012
4194HA, HB, HC Controllers
July 2018
2
Replacing Controller Parts
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Replacing the Process Differential
Pressure Scale
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Replacing the Relay
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Replacing the Case and Cover
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Replacing the Gauges
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Replacing the Links
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Link 1
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Link 2
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Link 3
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Link 4
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Replacing the Supply, Proportional, Reset,
Reset Valve, and Relief Tubing
Assemblies
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Replacing the Proportional Band Adjustment
Knob, Nozzle Assembly, and Set Point
Beam Assembly
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Replacing the Flapper Assembly and
Flexure Pivot Assembly
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Replacing the Proportional or Reset
Bellows
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Replacing the Reset Restriction Valve
(4194HB Controllers)
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Replacing the Rate/Reset Valve Assembly
(4194HC Controllers)
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Replacing the Differential Relief Valve
Assembly (suffix letter F)
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Replacing the Relief Valve Tubing
Assembly (suffix letter F)
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Calibration After Controller Maintenance
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Process Indicator Zero‐and‐Span
Calibration
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Flapper Alignment
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4194HA Proportional‐Only Controllers
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4194HB Proportional‐Plus‐Reset and
4194HC Proportional‐Plus‐Reset‐
Plus‐Rate Controllers
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Anti‐Reset Windup Valve (suffix letter F)
Calibration
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Remote Set Point (suffix letter M)
Maintenance
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Remote Set Point Assembly
Replacement
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Replacing Remote Set Point Parts
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Pivot Assembly A (Key 114)
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Pivot Assembly B (Key 115)
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Drive Flexure
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Remote Set Point Tubing
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Link A
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Link B
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Pressure Control Block for Remote
Set Point
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Remote Set Point Maintenance Calibration
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Remote Set Point Precalibration Procedures
.
Setting Remote Set Point Travel Stops
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Aligning Remote Set Point Linkage
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Remote Set Point Zero‐and‐Span
Adjustment
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Remote Set Point Linearity Adjustment
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Replacing Auto/Manual Station
(suffix letter E) Parts
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Disassembly of the Auto/Manual Station
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Assembly of the Auto/Manual Station
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Replacing the Auto/Manual Station Switch
Body Assembly, Lever O‐Ring, Switch
Body O‐Ring, and the Tubing Assembly
. .
Replacing the Auto/Manual Station Switch
Range Spring, Diaphragm Assembly,
Ball Seat, Tubing, and Ball
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Replacing the Auto/Manual Station Loader
Valve Plug and Valve Plug Spring
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6. Parts
Parts Kits
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Parts Ordering
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Abbreviations Used In Parts List
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Controller Parts
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Process and Set Point Indicator Assembly
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Remote Set Point Assembly
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Indicator Assembly
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Auto/Manual Station (suffix letter E)
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Controller Mounting Parts
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Fittings
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