Emerson Fisher 4194 Instruction Manual

Instruction Manual

D200156X012

4194HA, HB, HC Controllers

Fisherr 4194HA, HB, and HC Differential
Pressure Indicating Controllers

September 2014

Contents

1. Introduction

Scope of Manual 3.............................

Description 4.................................

Specifications 4...............................

Educational Services 4.........................

2. Installation, Mounting, and Connections

Controller Mounting Orientation 8...............

Pipestand Mounting 8.........................

Pressure Connections 8........................

Process Pressure Connections 10................

Supply Pressure 10............................

Vent Connection 11...........................

Remote Set Point (suffix letter M) Connection 11...
External Feedback Connection

(4194HB Controllers only) 11.................

3. 4194HA Proportional‐Only Controllers

Adjustments for 4194HA Controllers 12...........

Manual Set Point Adjustment 13.............

Remote Set Point (suffix letter M)

Adjustment 14..........................

Proportional Band Adjustment (PB ADJ) 14.....

Changing Controller Action 15...............

Switching The Auto/Manual Station

 (suffix letter E) 15.........................

Prestartup Checks for 4194HA Controllers 15......

Startup for 4194HA Controllers 16...............

Calibration for 4194HA Controllers 17............

General Calibration Instructions 17...........

Process Indicator Zero‐and‐Span

Calibration 17..........................

Remote Set Point (suffix letter M)

Zero‐and‐Span Adjustment 18.............

Flapper Alignment 19......................

Principle of Operation for 4194HA Controllers 20...

Overall Operation 20.......................

Remote Set Point Option

(suffix letter M) 21.......................

Auto/Manual Station Option

(suffix letter E) 21.......................

4. 4194HB Proportional‐Plus‐Reset
Controllers and 4194HC
Proportional‐Plus‐Reset‐Plus‐Rate
Controllers

Adjustments for 4194HB and HC Controllers 22....

Manual Set Point Adjustment 22.............

Remote Set Point (suffix letter M)

Adjustment 22..........................

Proportional Band Adjustment (PB ADJ) 22.....

Changing Controller Action 22...............

Reset (suffix letter B) Adjustment 23..........

Rate (suffix letter C) Adjustment 23...........

Anti‐Reset Windup (suffix letter F)

Adjustment 23..........................

Switching the Auto/Manual Station

(suffix letter E) 23.......................

Prestartup Checks for 4194HB and

HC Controllers 23...........................

Startup for 4194HB and HC Controllers 24.........

Calibration for 4194HB and HC Controllers 25......

General Calibration Instructions 25...........

Process Indicator Zero‐and‐Span

Calibration 26..........................

Remote Set Point (suffix letter M)

Zero‐and‐Span Calibration 27.............

Flapper Alignment 27......................

Anti‐Reset Windup Valve

(suffix letter F) Calibration 30..............

Principle of Operation for 4194HB and

HC Controllers 31...........................

Overall Operation 31.......................

Anti‐Reset Windup Option (suffix letter F) 34...
Remote Set Point Option (suffix letter M) 34...
Auto/Manual Station Option (suffix letter E) 34.

External Feedback Option 35................

5. Maintenance

Inspection and Maintenance 37..................

Troubleshooting 37............................

Changing Controller Action 41..................

Replacing the Differential Pressure Unit 42........

www.Fisher.com

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Replacing Controller Parts 43....................

Replacing the Process Differential

Pressure Scale 44........................

Replacing the Relay 44.....................

Replacing the Case and Cover 45.............

Replacing the Gauges 46....................

Replacing the Links 46......................

 Link 1 47................................

 Link 2 48................................

 Link 3 49................................

 Link 4 50................................

Replacing the Supply, Proportional, Reset,

Reset Valve, and Relief Tubing

Assemblies 51........................

Replacing the Proportional Band Adjustment

Knob, Nozzle Assembly, and Set Point

 Beam Assembly 52.....................

Replacing the Flapper Assembly and

Flexure Pivot Assembly 56................

Replacing the Proportional or Reset

Bellows 59.............................

Replacing the Reset Restriction Valve

(4194HB Controllers) 61..................

Replacing the Rate/Reset Valve Assembly

(4194HC Controllers) 61.................

Replacing the Differential Relief Valve

Assembly (suffix letter F) 62...............

Replacing the Relief Valve Tubing

Assembly (suffix letter F) 62...............

Calibration After Controller Maintenance 63.......

Process Indicator Zero‐and‐Span

Calibration 63..........................

Flapper Alignment 64......................

4194HA Proportional‐Only Controllers 65.....

4194HB Proportional‐Plus‐Reset and

4194HC Proportional‐Plus‐Reset‐

Plus‐Rate Controllers 65..................

Anti‐Reset Windup Valve (suffix letter F)

Calibration 67..........................

Remote Set Point (suffix letter M)

Maintenance 68............................

Remote Set Point Assembly

Replacement 69........................

Replacing Remote Set Point Parts 69..........

 Pivot Assembly A (Key 114) 69..............

 Pivot Assembly B (Key 115) 70..............

 Drive Flexure 71..........................

 Remote Set Point Tubing 71................

 Link A 71................................

 Link B 72................................

 Pressure Control Block for Remote

Set Point 72............................

Remote Set Point Maintenance Calibration 72.....

Remote Set Point Precalibration Procedures 72.

Setting Remote Set Point Travel Stops 73......

Aligning Remote Set Point Linkage 73.........

Remote Set Point Zero‐and‐Span

Adjustment 73..........................

Remote Set Point Linearity Adjustment 74.....

Replacing Auto/Manual Station

(suffix letter E) Parts 75......................

Disassembly of the Auto/Manual Station

Assembly of the Auto/Manual Station 75......

Replacing the Auto/Manual Station Switch

Body Assembly, Lever O‐Ring, Switch

Body O‐Ring, and the Tubing Assembly 76..
Replacing the Auto/Manual Station Switch

Range Spring, Diaphragm Assembly,

 Ball Seat, Tubing, and Ball 77.............

Replacing the Auto/Manual Station Loader

Valve Plug and Valve Plug Spring 78........

6. Parts

Parts Kits 79..................................

Parts Ordering 79.............................

Abbreviations Used In Parts List 79...............

Controller Parts 79............................

Process and Set Point Indicator Assembly 87.......

Remote Set Point Assembly 88..................

Indicator Assembly 89.........................

Auto/Manual Station (suffix letter E) 89...........

Controller Mounting Parts 92....................

Fittings 92................................

75....

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Instruction Manual

D200156X012

4194HA, HB, HC Controllers

September 2014

Section 11‐1‐

Introduction

Scope of Manual

This instruction manual provides installation, operating, calibration, maintenance, and parts ordering information for
the 4194HA, HB, and HC (high static pressure) differential pressure indicating controllers.

Portions of this manual apply only to specific 4194HA, HB, and HC controller configurations. These configurations are
indicated by letter suffixes in the type number that correspond to the mode and option designated in table 1‐2.

The specific controller type number (with letter suffixes) is located on the nameplate (figure 1‐1). Refer to table 1‐2 for
the definition of each 4194H controller type number.

Figure 1‐1. Fisher 4194H Differential Pressure Controller

NAMEPLATE

W5907

W5908

Do not install, operate, or maintain a 4194HA, HB, or HC controller without being fully trained and qualified in valve,
actuator, and accessory installation, operation, and maintenance. To avoid personal injury or property damage, it is

important to carefully read, understand, and follow all the contents of this manual, including all safety cautions and
warnings. If you have any questions about these instructions, contact your Emerson Process Management sales office

before proceeding.

3

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Description

The controllers described in this manual provide differential control with options as shown in table 1‐2.

D 4194HA controllers: Proportional‐only control

D 4194HB controllers: Proportional‐plus‐reset control

D 4194HC controllers: Proportional‐plus‐reset‐plus‐rate control

4194HA, HB, or HC controllers show process differential pressure and set point on an easy‐to‐read process scale. The
controller output is a pneumatic signal that operates a final control element.

Specifications

Specifications for 4194HA, HB, and HC controllers are listed in table 1‐1.

Educational Services

For information on available courses for 4194HA, 4194HB, and 4194HC controllers, as well as a variety of other
products, contact:

Emerson Process Management
Educational Services, Registration
Phone: [phone] or [phone]
e‐mail: [e-mail]
http://www.emersonprocess.com/education

4

Instruction Manual

D200156X012

Table 1‐1. Specifications

4194HA, HB, HC Controllers

September 2014

Available Configurations

See table 1‐2

Input Signal (Differential Pressure Sensing Element
Range)

Differential Pressure Range: See table 1‐3
Maximum Safe Working Pressure: See table 1‐3

Output Signal

Proportional‐Only, Proportional‐Plus‐Reset, or
Proportional‐Plus‐Reset‐Plus‐Rate Range: 0.2 to 1.0

bar (3 to 15 psig) or 0.4 to 2.0 bar (6 to 30 psig)

(1)

Action: Field‐reversible between direct

(increasing
differential pressure increases output pressure) or
reverse

(1)

(increasing differential pressure decreases

output pressure)

Process Scale

Standard scale is matched to the range of the
differential pressure sensing element. Linear, square
root, and optional scales

(2)

available

Process Connections (To Differential Pressure Unit)

Standard: 1/4 NPT internal stainless steel
(all input ranges)

Optional: 1/2 NPT internal stainless steel

Supply And Output Connections

1/4 NPT internal

Supply Pressure Requirements

See table 1‐4

Supply Pressure Medium

Air or natural gas
Air: Supply pressure must be clean, dry air that meets

the requirements of ISA Standard 7.0.01.
Natural Gas: Natural gas must be clean, dry, oil‐free,

and noncorrosive. H

S content should not exceed 20

2

ppm.
A maximum 40 micrometer particle size in the air

system is acceptable. Further filtration down to 5
micrometer particle size is recommended. Lubricant
content is not to exceed 1 ppm weight (w/w) or
volume (v/v) basis. Condensation in the air supply
should be minimized.

-continued-

Remote Set Point Pressure Ranges

0.2 to 1.0 bar (3 to 15 psig) or

0.4 to 2.0 bar (6 to 30 psig)

Controller Adjustments

Proportional Band: 5 to 500% of process scale range

Reset: Adjustable from 0.01 to more than 74 minutes

per repeat (from 100 to less than 0.0135 repeats per
minute)

Rate: Adjustable from 0 to 20 minutes

Set Point: Continuously adjustable from 0 to 100% of

the scale range

Controller Performance

Repeatability: 0.4% of output span

Dead Band: Less than 0.2% of process scale range

Steady‐State Air Consumption

(3)

Without Auto/Manual Station

0.2 to 1.0 Bar (3 to 15 Psig) Output:

0.09 m

0.4 to 2.0 Bar (6 to 30 Psig) Output:

0.13 m

3

/hr (3.5 scfh)

3

/hr (5.0 scfh)

With Auto/Manual Station (suffix letter E)

0.2 to 1.0 Bar (3 to 15 Psig) Output:

0.28 m

2.0 to 4.0 Bar (6 to 30 Psig) Output:

0.28 m

Delivery Capacity

0.2 to 1.0 Bar (3 to 15 Psig) Output:

6.4 m

0.4 to 2.0 Bar (6 to 30 Psig) Output:

9.4 m

Exhaust Capacity

3

/hr (10.0 scfh)

3

/hr (10.0 scfh)

3

/h (240 scfh)

3

/h (370 scfh)

(3)

(3)

0.2 to 1.0 Bar (3 to 15 Psig) Output:

3

/h (186 scfh)

5.0 m

0.4 to 2.0 Bar (6 to 30 Psig) Output:

3

/h (295 scfh)

7.9 m

Operative Ambient Temperature Limits

(4)

–40 to 70°C (–40 to 160°F)

5

4194HA, HB, HC Controllers

September 2014

Table 1‐1. Specifications (continued)

Instruction Manual

D200156X012

Hazardous Area Classification

Complies with the requirements of ATEX Group II
Category 2 Gas and Dust

Differential Pressure Unit: 21.5 kg (47 lb)

Total Weight (controller and differential pressure
unit): 26 kg (57 lb) (with a Barton 199 Differential

Pressure Unit)

Declaration of SEP

Housing

Designed to NEMA 3 and IEC 529, IP54 specifications

Fisher Controls International LLC declares this
product to be in compliance with Article 3 paragraph
3 of the Pressure Equipment Directive (PED) 97 / 23 /

Mounting

Controller is mounted on a pipestand. See figure 2‐1.

EC. It was designed and manufactured in accordance
with Sound Engineering Practice (SEP) and cannot
bear the CE marking related to PED compliance.

Approximate Weight

Controller: 4.5 kg (10 lb) without the differential
pressure unit

NOTE: Specialized instrument terms are defined in ANSI/ISA Standard 51.1 − Process Instrument Terminology.

1. With Barton 199 differential pressure unit. For ranges other than those listed in table 1‐3, contact your Emerson Process Management sales office.

2. Consult your Emerson Process Management sales office for additional information.

3. Normal m

4. Also for transportation and storage limits.

3

/hr: normal cubic meters per hour (0°C and 1.01325 bar absolute). Scfh: standard cubic feet per hour (60°F and 14.7 psia).

However, the product may bear the CE marking to
indicate compliance with other applicable EC
Directives.

Table 1‐2. Available Configurations

CONTROLLER

4194HA

4194HB

4194HC

1. Reverse‐acting constructions are designated by an R added to the type number.

(1)

4194HA
4194HAE
4194HAM
4194HAME

4194HB
4194HBE
4194HBF
4194HBFE
4194HBM
4194HBME
4194HBFM
4194HBFME

4194HC
4194HCE
4194HCF
4194HCFE
4194HCM
4194HCME
4194HCFM
4194HCFME

Proportional‐Only

X
X
X
X

MODES OPTIONS

Proportional‐Plus‐

Reset

X
X
X
X
X
X
X
X

Proportional‐Plus‐

Reset‐Plus‐Rate

X
X
X
X
X
X
X
X

Anti‐Reset

Windup

X
X

X
X

X
X

X
X

Remote Set

Point

X
X

X
X
X
X

X
X
X
X

Internal Auto/

Manual Station

X

X

X

X

X

X

X

X

X

X

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Instruction Manual

D200156X012

4194HA, HB, HC Controllers

September 2014

Table 1‐3. Process Sensor (Barton 199) Range and Pressure Ratings

DIFFERENTIAL PRESSURE RANGE

(1)

SAFE WORKING PRESSURE

Bar Psig

0 to 15 (0 to 1)
0 to 30 (0 to 2)
0 to 40 (0 to 2.8)
0 to 50 (0 to 3.4)

68.9 1000 Stainless steel

0 to 60 (0 to 4)
0 to 75 (0 to 5)

0 to 15 (0 to 1)
0 to 30 (0 to 2)

Psig (bar)

0 to 40 (0 to 2.8)
0 to 50 (0 to 3.4)

172 2500 Steel

0 to 60 (0 to 4)
0 to 75 (0 to 5)

0 to 15 (0 to 1)
0 to 30 (0 to 2)
0 to 40 (0 to 2.8)
0 to 50 (0 to 3.4)

414 6000 Steel

0 to 60 (0 to 4)
0 to 75 (0 to 5)

0 to 20 (0 to 50)
0 to 25 (0 to 62)
0 to 50 (0 to 124)

68.9 1000 Stainless steel
0 to 75 (0 to 186)
0 to 100 (0 to 248)

0 to 20 (0 to 50)
0 to 25 (0 to 62)

Inches w.c. (mbar)

0 to 50 (0 to 124)

172 2500 Steel
0 to 75 (0 to 186)
0 to 100 (0 to 248)

0 to 20 (0 to 50)
0 to 25 (0 to 62)
0 to 50 (0 to 124)

414 6000 Steel
0 to 75 (0 to 186)
0 to 100 (0 to 248)

1. Differential pressure ranges are in English units of measurement; metric equivalents are shown here for reference only. Consult your Emerson Process Management sales office for special
differential pressure ranges.

2. The Barton 199 differential pressure unit may be pressured to this value without permanent zero shift or structural damage to controller components.

(2)

HOUSING

MATERIAL

Table 1‐4. Supply Pressure Requirements

Output Signal Range Normal Operating Supply Pressure

Bar

Psig

1. If this pressure is exceeded, control stability may be impaired.

2. If this pressure is exceeded, damage to the controller may result.

0.2 to 1.0 1.4 2.8

0.4 to 2.0 2.4 2.8

Maximum Pressure to Prevent

(1)

Internal Damage

3 to 15 20 40
6 to 30 35 40

(2)

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4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Section 2 2‐2‐

Installation, Mounting, and Connections

WARNING

To avoid personal injury or property damage resulting from the sudden release of pressure:

D Always wear protective clothing, gloves, and eyewear when performing any installation operations.

D Personal injury or property damage may result from fire or explosion if natural gas is used as the supply medium and

preventive measures are not taken. Preventive measures may include, but are not limited to, one or more of the
following: Remote venting of the unit, re‐evaluating the hazardous area classification, ensuring adequate ventilation,
and the removal of any ignition sources. For information on remote venting of this controller, refer to page 11.

D Check with your process or safety engineer for any additional measures that must be taken to protect against process

media.

D If installing into an existing application, also refer to the WARNING at the beginning of the Maintenance section of this

instruction manual.

Controller Mounting Orientation

Mount the controller with the housing vertical, as shown in figure 2‐1, so the vent points down.

Pipestand Mounting

A 4194H controller mounts on a pipestand. Install with the vent opening facing down. Secure the mounting coupling
to the pipestand by three set screws as shown in figure 2‐1.

Pressure Connections

WARNING

To avoid personal injury or property damage resulting from the sudden release of pressure, do not install any system
component, including the differential pressure unit, where service conditions could exceed the limits given in this manual.
Use pressure‐relieving devices as required by government or accepted industry codes and good engineering practices.

Refer to figures 2‐1, 2‐2, and 2‐3 for the location of all input and output connections for the controller and differential
pressure unit. Also, refer to the differential pressure unit instruction manual for specific information about
connections and piping.

Supply, output, vent, and remote set point connections are 1/4 NPT. Use 1/4 or 3/8‐inch pipe or tubing for supply,
output, vent, and remote set point piping.

Process pressure connections are 1/4 or 1/2 NPT (optional). When installing process piping to the differential pressure
unit attached to the controller, follow accepted engineering, installation, and safety practices to insure the safe and
accurate transmission of the process differential pressure to the differential pressure unit. Install shutoff valves, vents,
drains, or seal systems as required by accepted practices.

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Instruction Manual

D200156X012

4194HA, HB, HC Controllers

September 2014

Figure 2‐1. Right Side View of Controller

SET SCREW

NOTE:
1 LOW PRESSURE CONNECTION ON A BARTON 199
DIFFERENTIAL PRESSURE UNIT.

W3635-1

(3 REQ'D)

BARTON 199
DIFFERENTIAL
PRESSURE UNIT

1/2 NPT
PRESSURE CONNECTION

1/4 NPT PRESSURE
CONNECTION

PIPESTAND MOUNTING
BRACKET

PIPESTAND

1

1

Figure 2‐2. Connections

1/4 NPT REMOTE SET
POINT CONNECTION

REMOTE SET POINT
CONNECTION

1/2 NPT

1

TOP VIEW

1/4 NPT

NOTE:
1 HIGH PRESSURE CONNECTION ON A BARTON 199 DIFFERENTIAL PRESSURE UNIT.

18A5903‐B
A3000-1

FRONT VIEW

1

LEFT SIDE VIEW

1/4 NPT VENT

1/4 NPT
2 HOLES

1/4 NPT
OPTIONAL EXTERNAL
FEEDBACK CONNECTION

SUPPLY PRESSURE

CONTROLLER
OUTPUT PRESSURE

BOTTOM VIEW

9

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Process Pressure Connections

Process pressures are piped to the connections on the ends of the differential pressure unit (figure 2‐3). Refer to the
differential pressure unit instruction manual for the high and low pressure connections.

Figure 2‐3. Simplified Control Loop Diagram

LOW

2

PRESSURE
CONNECTIONS

HIGH PRESSURE
CONNECTIONS

SUPPLY
PRESSURE

LOW PRESSURE
PIPING

OUTPUT
SIGNAL

HIGH PRESSURE PIPING

1

ORIFICE PLATE

NOTE:
1 TO ALLOW A REAR VIEW OF THE CONTROLLER/DIFFERENTIAL PRESSURE UNIT,
THE SCHEMATIC SHOWS PROCESS FLOW FROM RIGHT TO LEFT.
2 SEE FIGURE 2‐1 FOR LOW PRESSURE CONNECTIONS.

W5910

When installing process piping, follow accepted practices to ensure accurate transmission of the process pressures to
the differential pressure unit. Install a three‐valve bypass, shutoff valves, vents, drains, or seal systems as needed in the
process pressure lines.

If the instrument is located such that the adjacent process pressure lines will be approximately horizontal, the lines
should slope downward to the instrument for liquid‐filled lines and upward toward the instrument for gas‐filled lines.
This will reduce the chance of air becoming trapped in the sensor with liquid‐filled lines or of condensate becoming
trapped with gas‐filled lines. The recommended slope is 83 millimeters per meter (1 inch per foot).

Supply Pressure

WARNING

Severe personal injury or property damage may occur if the instrument supply medium is not clean, dry air or oil‐free,
noncorrosive gas. While use and regular maintenance of a filter that removes particles larger than 40 micrometer in
diameter will suffice in most applications, check with an Emerson Process Management field office and industry instrument
air quality standards for use with corrosive gas or if you are unsure about the proper amount or method of air filtration or
filter maintenance.

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Instruction Manual

D200156X012

Supply pressure must be clean, dry air or noncorrosive gas that meets the requirements of ISA 7.0.01. A maximum 40
micrometer particle size in the air system is acceptable. Further filtration down to 5 micrometer particle size is
recommended. Lubricant content is not to exceed 1 ppm weight (w/w) or volume (v/v) basis. Condensation in the air
supply should be minimized. Natural gas must be clean, dry, oil‐free, and noncorrosive. H
20 ppm.

Use a suitable supply pressure regulator to reduce the supply pressure source to 1.4 bar (20 psig) for an output signal
range of 0.2 to 1.0 bar (3 to 15 psig) and to 2.4 bar (35 psig) for an output signal range of 0.4 to 2.0 bar (6 to 30 psig).

4194HA, HB, HC Controllers

September 2014

S content should not exceed

2

Vent Connection

WARNING

Personal injury or property damage could result from fire or explosion of accumulated gas, or from contact with hazardous
gas, if a flammable or hazardous gas is used as the supply pressure medium. Because the controller case and cover
assembly do not form a gas‐tight seal when the assembly is enclosed, a remote vent line, adequate ventilation, and
necessary safety measures should be used to prevent the accumulation of flammable or hazardous gas. However, a remote
vent pipe alone cannot be relied upon to remove all flammable or hazardous gas. Vent line piping should comply with local
and regional codes and should be as short as possible with adequate inside diameter and few bends to reduce case pressure
buildup.

CAUTION

When installing a remote vent pipe, take care not to over‐tighten the pipe fitting in the vent connection. Excessive torque
will damage the threads in the connection.

If a remote vent is required, the vent line must be as short possible with a minimum number of bends and elbows. Vent
line piping should have a minimum inside diameter of 19 mm (3/4 inches) for runs up to 6.1 m (20 feet) and a
minimum inside diameter of 25 mm (1 inch) for runs from 6.1 to 30.5 m (20 to 100 feet).

If a remote vent is not required, the vent opening (figure 2‐2) must be protected against the entrance of any foreign
material that could plug it. Check the vent periodically to be certain it is not plugged.

Remote Set Point (suffix letter M) Connection

If the controller has the remote set point option, connect the remote set point pressure to the top of the controller
case at the location shown in figure 2‐2. If pressure is supplied to the remote set point connection with a regulator, a
small bleed orifice should be placed between the regulator and remote set point connection to prevent pressure
variations due to regulator lock‐up.

External Feedback Connections (4194HB Controllers Only)

When a secondary controller in an override application has this option, reset windup is minimized in the secondary
controller. Connect the external feedback connection of the secondary controller to the output of the
customer‐supplied high or low select relay. See figure 2‐2.

11

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Section 3 3‐3‐

4194HA Proportional‐Only Controllers

Adjustments for 4194HA Controllers

Note

Some of the following procedures require adjusting the proportional band knob between DIRECT and REVERSE. If this is done, it
will be necessary to set the proportional band knob to 400 (direct or reverse action) before replacing the proportional band
indicator cover.

This section includes descriptions of adjustments and procedures for prestartup and startup. Location of adjustments
is shown in figure 3‐1. To better understand the adjustments and overall operation of the controller, refer to the
principle of operation and the schematic diagrams (figures 3‐3, 4‐2, and 4‐3). Unless otherwise noted, refer to figure
6‐1 for key number locations.

12

Instruction Manual

D200156X012

Figure 3‐1. Location of Controller Parts and Adjustments

DRIVE ARM
LOCKING SCREW

PIVOT BRACKET

DRIVE ARM

CONNECTING LINK 1

ZERO ADJUSTMENT

ZERO ADJUSTMENT
LOCKING SCREW

SPAN
ADJUSTMENT

SUPPLY PRESSURE
GAUGE

4194HA, HB, HC Controllers

September 2014

SET POINT
ADJUSTMENT

PROCESS
INDICATOR

PROPORTIONAL
BAND INDICATOR
COVER

PROPORTIONAL
BAND ADJUSTMENT
KNOB

OUTPUT
PRESSURE
GAUGE

SEE VIEW A

NOTE:
1 ON CONTROLLERS EQUIPPED WITH REMOTE SET POINT
OPTION, THIS IS THE REMOTE SET POINT INDICATOR.

W3688‐1

PROCESS SPAN
ADJUSTMENT

35A7374‐B

REMOTE SET POINT
SPAN ADJUSTMENT

SIDE VIEW OF SET POINT / PROCESS

INDICATOR ASSEMBLY

FRONT VIEW

SCREW 1

SCREW 2

SCREW 3

56A9752‐S SHT 1

SIDE VIEW OF CONTROLLER

SHOWING FLAPPER LEVELING SCREWS

Manual Set Point Adjustment

To adjust the set point, open the controller cover and move the set point indicator until the desired value on the
process differential pressure scale is below the line on the set point indicator. Move the adjustment to the right to
increase the set point and to the left to decrease it.

13

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Remote Set Point (suffix letter M) Adjustment

CAUTION

Do not manually move the set point indicator on controllers with remote set point. Moving the set point indicator could
damage the controller.

If the controller is equipped with the remote set point option (figure 3‐2), vary the remote set point pressure to
change the set point. Increase the pressure to increase the set point and decrease the pressure to decrease the set
point.

Figure 3‐2. Parts and Adjustments, Remote Set Point Option

PIVOT
ASSEMBLY A

36A9751‐C
B1668‐4

GUIDE FLEXURE

TIE BAR

REMOTE SET POINT ZERO ADJUSTMENT SCREW
ZERO ADJUSTMENT LOCKING SCREW

MOUNTING SCREW

LINK A

MOUNTING
SCREW

ADJUSTMENT
SCREW

PIVOT
ASSEMBLY B

LINK B

LINEARITY
ADJUSTMENT

FRONT VIEW

DRIVE FLEXURE

LOWER TRAVEL
STOP

UPPER TRAVEL
STOP

CAPSULES

SIDE VIEW

Proportional Band Adjustment (PB ADJ)

The proportional band adjustment determines the output sensitivity of the controller. The proportional band knob is
marked in percentages of process differential pressure required to drive the controller from zero output to full output.

For example, a typical 4194H unit offers 0.2 to 1.0 bar (3 to 15 psig) output. Furthermore, this controller comes
equipped with a differential pressure unit capable of sensing a process pressure differential ranging from 0 to 1.0 bar

14

Instruction Manual

D200156X012

(0 to 15 psig). Then, at a proportional band setting of 100 percent DIRECT, the controller output goes from 3 to 15
psig as the process pressure differential goes from 0 to 15 psig. If the proportional band setting is subsequently
changed to 50 percent DIRECT, the controller output would change from 3 to 15 psig as the process pressure
differential changed from 0 to 7.5 psig.

Adjusting the proportional band has minimal effect on the set point.

4194HA, HB, HC Controllers

September 2014

Changing Controller Action

Controller action is switchable from direct to reverse or vice versa by simply loosening the screws on the proportional
band indicator cover and moving the cover out so the proportional band knob can be rotated to the desired action.
The white portion of the adjustment enables direct controller action. The black portion enables reverse controller
action.

Switching The Auto/Manual Station (suffix letter E)

Note

Switching the controller between automatic and manual mode without balancing can disturb the process and cause controller
cycling.

Refer to figure 6‐5 if the controller has the auto/manual option.

To switch from automatic to manual mode, you must balance the manual output with the controller output.

Two balance methods are available to equalize the manual output with the controller output.

To switch from automatic to manual mode, carefully adjust the loader knob until the metal ball inside the plastic tube
moves into the switching zone. Then move the automatic/manual switch to MANUAL. Turn the loader knob clockwise
to increase the controller output or counterclockwise to decrease it.

To switch from manual to automatic mode, adjust the set point manually or with remote set point pressure to move
the ball into the switching zone. Turn the switch to AUTOMATIC and adjust the set point manually or with remote set
point pressure to control the output.

When the automatic/manual switch is in AUTOMATIC, adjusting the loader knob has no effect on the controller
output. When the automatic/manual switch is in MANUAL, changing the set point adjustment has no effect on the
controller output.

Prestartup Checks for 4194HA Controllers

Refer to figure 3‐1 for location of adjustments and refer to figure 6‐1 for location of key numbers.

When performing the checks, open loop conditions must exist. An open loop exists when the controller output does
not affect the input pressure or other control signal to the controller.

Note

If the controller has the auto/manual option (suffix letter E), be sure the controller is in the automatic mode before performing the
prestartup checks.

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1. Connect supply pressure to the supply pressure regulator and be sure it is delivering the proper supply pressure to
the controller. Provide a means of measuring the controller output pressure. Also, provide a means of applying
process differential pressure to the differential pressure unit.

2. For a controller with remote set point (suffix letter M), connect regulated pressure of 0.2 to 1.0 bar (3 to 15 psig)
or 0.4 to 2.0 bar (6 to 30 psig) to the remote set point connection at the top of the controller case.

3. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36).

4. Set the proportional band between DIRECT and REVERSE.

5. Adjust the process differential pressure until the controller indicates 50 percent of the input range. The process
indicator should point out the process differential pressure within ±1 percent of the input span.

6. If the process indicator is out of calibration, refer to the process indicator zero‐and‐span adjustment procedures in
the Calibration section. Also, check the accuracy of the process indicator at other points on the scale.

7. For controllers with manual set point, move the set point indicator to 50 percent of the scale range. For controllers
with remote set point (suffix letter M), adjust the remote set point pressure until the set point moves to 50 percent
of the scale range.

8. The output of the controller should be:

D 0.62 ±0.007 bar (9 ±0.1 psig) for a 0.2 to 1.0 bar (3 to 15 psig) output

D 1.2 ±0.01 bar (18 ±0.2 psig) for a 0.4 to 2.0 bar (6 to 30 psig) output

9. Adjust the proportional band to 20 percent DIRECT. The output of the controller should remain essentially the
same.

D 0.62 ±0.017 bar (9 ±0.25 psig) for a 0.2 to 1.0 bar (3 to 15 psig) output

D 1.2 ±0.03 bar (18 ±0.5 psig) for a 0.4 to 2.0 bar (6 to 30 psig) output

10. Adjust the proportional band to 20 percent REVERSE. The output of the controller should remain essentially the
same.

D 0.62 ±0.017 bar (9 ±0.25 psig) for a 0.2 to 1.0 bar (3 to 15 psig) output

D 1.2 ±0.03 bar (18 ±0.5 psig) for a 0.4 to 2.0 bar (6 to 30 psig) output

11. If the controller output is out of tolerance in steps 8, 9, or 10, the flapper needs to be aligned. Refer to the flapper
alignment procedure.

12. If the controller output is within tolerance, replace the proportional band cover and go to the startup procedure.

Startup for 4194HA Controllers

Perform the prestartup checks and, if necessary, calibrate the controller prior to this procedure.

Note

When performing the startup procedure, keep in mind the initial settings are guidelines. They will vary depending on the actual
process being controlled.

1. Be sure the supply pressure regulator is delivering the proper supply pressure to the controller.

2. For controllers with:

D manual set point:

Move the set point indicator to the desired set point.

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D remote set point:

a. See figure 2‐2 for the location of the remote set point connection. Connect an adjustable pressure source to

the remote set point connection.

b. Adjust the pressure source until the set point indicator reaches the desired set point. Remember: Increasing

the remote set point pressure increases the set point of direct‐acting controllers.

3. Set the proportional band adjustment to 100 percent for fast processes. For slow processes, calculate the
proportional band percentage from the equation below:

4194HA, HB, HC Controllers

September 2014

Proportional
Band
Adjustment

For example:

4. Create a load upset by momentarily changing the set point. Check for system cycling. If the system does not cycle,
lower the proportional band setting (thus raising the gain) and disturb the system again by changing the set point.
Continue this procedure until the system cycles. At this point, double the proportional band setting (proportional
band setting X 2).

200 AllowableOvershoot

+

PressureSpan

200 2Psig

30Psig

^ 13%

Calibration for 4194HA Controllers

WARNING

To avoid personal injury or property damage resulting from the sudden release of pressure, do not exceed the operating
limits given in this manual.

General Calibration Instructions

Note

If the controller has the auto/manual option, be sure the controller is in the automatic mode before performing calibration.

If the prestartup checks revealed faulty controller operation, perform the calibration described in this section. These
instructions are valid for either shop or field calibration, provided open process loop conditions exist. Unless otherwise
noted, key numbers are found in figure 6‐1.

Process Indicator Zero‐and‐Span Calibration

Before starting this procedure:

D Provide a regulated process differential pressure to the differential pressure unit.

D Provide a regulated supply pressure to the controller. Do not exceed the normal operating pressure in table 1‐4.

Note

Any change in process indicator span will require readjustment of the process indicator zero adjustment screw.

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Refer to figure 3‐1 for location of adjustments.

1. Remove two screws (key 6) and lift off the proportional band indicator cover (key 36).

2. Set the proportional band between DIRECT and REVERSE.

3. The process indicator should be aligned with the indicator subassembly as shown in figure 5‐6. If not, loosen the
zero adjustment locking screw and adjust the fine zero adjustment to align the process indicator and indicator
subassembly. See figure 6‐4.

4. Adjust the process differential pressure until the controller indicates 50 percent of the input range.

5. The process indicator should point to 50 percent of the process scale range. If not, loosen the drive arm locking
screw (key 331, figure 6‐2) that holds the drive arm (key 322) to the shaft extension (key 321) and readjust the drive
arm on the shaft until the process indicator points to 50 percent of the process scale range. Tighten the drive arm
locking screw.

6. Adjust the process differential pressure to the lower limit of the input span. Note the position of the process
indicator.

7. If necessary, adjust the process indicator to the lowest limit of the input scale by loosening the zero adjustment
locking screw and turning the zero adjustment screw.

8. Adjust the process differential pressure to the upper limit of the input span. Note whether the process indication is
above or below the upper limit of the process scale.

9. Adjust the span screw as follows: Clockwise to increase span for a low indication or counterclockwise to decrease
span for a high indication. Adjust the span screw to correct one‐half the error.

10. Repeat steps 6 through 9 until the error is eliminated.

11. Adjust the process differential pressure to 50 percent of the input range. The process indicator should point to the
mid‐scale value within ±1 percent of the input span. If the process indicator does not point to the proper value,
select the appropriate instructions, below:

D If the process indicator error at mid‐range is greater than ±1 percent but not greater than ±2 percent, turn the

zero adjustment screw to bring the process indicator within ±1 percent at mid‐range. Then, check the process
indicator accuracy at the lower and upper scale limits, to verify it is within ±1 percent of the input span.

After adjusting the process indicator to ±1 percent at the low, mid‐range, and upper scale limits, proceed with
step 12.

D If the process indicator error at mid‐range is greater than ±2 percent, loosen the two screws in the drive arm (key

322, figure 6‐2) and lengthen or shorten the drive arm approximately 6.3 mm (1/4‐inch). Then, repeat steps 6
through 11.

After adjusting the process indicator to ±1 percent at the low, mid‐range, and upper scale limits, proceed with
step 12.

12. Perform the flapper alignment procedure. Install the proportional band indicator cover (key 36) and tighten the two
screws (key 6).

Remote Set Point (suffix letter M) Zero‐and‐Span Adjustment

Refer to figure 3‐1 for location of adjustments. Refer to figures 6‐1 and 6‐2 for key number locations.

Note

Any adjustment of the set point span adjustment screw will require readjustment of the set point zero adjustment screw. Refer to
figure 3‐1.

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4194HA, HB, HC Controllers

September 2014

1. Remove two screws (key 6) and lift off the proportional band indicator cover (key 36).

2. Set the proportional band between DIRECT and REVERSE.

3. Adjust the set point pressure to the low limit of the set point input range. Note the position of the set point
indicator. Loosen the set point zero adjustment locking screw and adjust the zero adjustment screw (figure 3‐1)
until the set point indicator aligns with the lowest scale limit.

When the set point indicator is properly aligned with the low scale limit, tighten the zero adjustment locking screw.

4. Adjust the set point pressure to the upper limit of the input span. Note whether the indication is above or below the
upper limit of the process scale.

5. Adjust the span screw as follows: Clockwise to increase span for a low indication; counterclockwise to decrease span
for a high indication. Adjust the span screw to correct one‐half the error.

6. Repeat steps 3 through 5 until the error is eliminated.

7. Adjust the remote set point pressure to 50 percent of the remote set point range.

8. Make sure the remote set point indicator is within ±1 percent of the mid‐scale mark and, if so, proceed to step 10. If
the set point indicator is not within ±1 percent but is within ±2 percent of the mid‐scale mark then proceed with
step 9. If the set point indicator is not within ±2 percent, proceed to the remote set point calibration in Section 5.

9. Loosen the zero adjustment locking screw and adjust the zero screw to correct for one‐half the error. Tighten the
locking screw.

10. Adjust the remote set point pressure to the lower and upper range limits and make sure the set point indicator is
within ±1 percent.

11. Install the proportional band indicator cover and tighten the two screws.

12. If necessary, proceed to the process indicator zero‐and‐span calibration procedure in this section. Otherwise,
proceed to the flapper alignment procedure in this section.

Flapper Alignment

Note

Perform the process indicator zero‐and‐span calibration procedure and, if necessary, the remote set point calibration procedure
before the flapper alignment.

Flapper leveling screw numbers and adjustments are shown in figure 3‐1.

Provide a means of applying supply pressure to the controller. Also, provide an accurate means of measuring output
pressure.

Apply process differential pressure to the differential pressure unit. Refer to figures 2‐1 and 2‐2 for the differential
pressure unit connections.

1. For a controller with manual set point, move the set point indicator to 50 percent of the scale range. For a controller
with remote set point (suffix letter M), adjust the remote set point pressure until the set point indicator is at 50
percent of the scale range.

2. Apply differential pressure equal to 50 percent of the input range.

Note

If a pressure source is not available to pressure the input element (differential pressure unit) to 50 percent of range, an alternate
method is to disconnect link 1 at the drive arm and tape the process indicator at 50 percent of the input range. Note the hole from
which link 1 was removed for proper replacement.

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This method should only be used if pressure is not available to drive the differential pressure unit to 50 percent.

3. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36). Adjust the
proportional band adjustment between DIRECT and REVERSE.

4. The controller output should be 0.62 ±0.007 bar (9 ±0.1 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 number 2.

5. Adjust the proportional adjustment to 20 percent DIRECT (direct acting).

6. The controller output should be 0.62 ±0.02 bar (9 ±0.25 psig) or 1.2 ±0.04 bar (18 ±0.5 psig). If not, adjust flapper
leveling screw number 3.

7. Adjust the proportional band adjustment to 20 percent REVERSE (reverse acting).

8. The controller output should be 0.62 ±0.02 bar (9 ±0.25 psig) or 1.2 ±0.04 bar (18 ±0.5 psig). If not, adjust flapper
leveling screw number 1.

9. Repeat steps 5 through 8 until the output of the controller remains in tolerance without further leveling screw
adjustments.

10. If link 1 was disconnected, remove the tape and reconnect link 1 to the drive arm.

11. Set the proportional band adjustment to 400 percent in the desired controller action. Replace the proportional
band indicator cover (key 36) and install the machine screws (key 6).

Principle of Operation for 4194HA Controllers

Overall Operation

Refer to the schematic diagram in figure 3‐3.

Figure 3‐3. Schematic for Fisher 4194HA Controller

SET POINT

PROCESS POINTER

REMOTE SET POINT
CONNECTED HERE

INPUT ELEMENT
CONNECTED HERE

CONNECTING
LINK

SUPPLY PRESSURE

OUTPUT PRESSURE

NOZZLE PRESSURE

46A9764‐C
B1907

INDICATOR

PROPORTIONAL
BELLOWS

BEAM

FLAPPER

RESET BELLOWS (VENTED)

NOZZLE

PROPORTIONAL
BAND ADJUSTMENT

SUPPLY
PRESSURE

FEEDBACK
LINK

FEEDBACK
MOTION

DIRECT ACTION
QUADRANT

FLAPPER DETAIL

OUTPUT PRESSURE
TO FINAL CONTROL
ELEMENT

REVERSE ACTION
QUADRANT

FLAPPER
PIVOT

INPUT MOTION

RELAY

20

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The process differential pressure input element is connected to the process indicator and to the flapper by connecting
links. As the process differential pressure increases (in a direct‐acting controller), the flapper moves toward the nozzle,
restricting flow through the nozzle and increasing nozzle pressure. When this occurs, relay action increases the output
pressure (delivery) of the controller. Output pressure is fed back to the proportional bellows. The action of the
proportional bellows counteracts the flapper movement that resulted from the process differential pressure change
and backs the flapper away from the nozzle until equilibrium is reached.

The set point adjustment changes the distance between the nozzle and flapper as does a change in process differential
pressure except that when the set point is changed, the nozzle moves with respect to the flapper.

The proportional band adjustment knob positions the nozzle on the flapper. Increasing (widening) the proportional
band moves the nozzle to a position on the flapper where less input and more feedback motion occurs, which
decreases the gain of the controller. Decreasing (narrowing) the proportional band moves the nozzle toward a
position where more input and less feedback motion occurs, which increases the gain. The controller action is
changed from DIRECT to REVERSE by turning the proportional band adjustment knob to position the nozzle on the
flapper quadrant to a point where the direction of the flapper motion versus input motion is reversed (see flapper
detail in figure 5‐11). With the controller in the reverse‐acting mode, an increase in process differential pressure
causes a decrease in output pressure.

4194HA, HB, HC Controllers

September 2014

Remote Set Point Option (suffix letter M)

The capability to adjust the controller set point from a remote location is available with all 4194H controllers. This
option is designated by the suffix letter M in the type number.

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 adjustment via a 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 Option (suffix letter E)

Controllers with the auto/manual option (designated by the suffix letter E in the type number) have piping on the
output side of the relay as shown in figure 4‐5. Supply pressure to the relay is also applied to the manual loader. The
manual loader, functioning as a regulator, applies pressure to one side of the plastic tube and to the auto/manual
switch. Output pressure from the relay registers on the other side of the plastic tube as well as in the auto/manual
switch.

When the auto/manual switch is in the MANUAL position, the output of the manual loader is channeled through the
auto/manual switch and becomes the output of the controller. When the auto/manual switch is in the AUTO position,
the output of the relay is channeled through the switch to become the output of the controller.

Before the auto/manual switch is operated, the output of the relay must equal the output of the manual loader to
avoid bumping the process. Adjusting the set point varies the pressure on the left‐hand side of the plastic tube.
Adjusting the manual loader knob varies the pressure on the right‐hand side. When the pressures are equal, the metal
ball is centered in the tube. Pressure imbalance forces the ball to one end of the tube where it forms a seal, blocking air
flow through the tube.

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Section 44‐4‐

4194HB Proportional‐Plus‐Reset Controllers And 4194HC
Proportional‐Plus‐Reset‐Plus‐Rate Controllers

Adjustments for 4194HB and HC Controllers

This section includes descriptions of adjustments and procedures for prestartup and startup.

Location of adjustments is shown in figure 3‐1. To better understand the adjustments and overall operation of the
controller, refer to the principle of operation and the schematic diagrams (figures 4‐2 through 4‐6). Unless otherwise
noted, key numbers given in this section can be found in figure 6‐1.

When placing the controller into operation use the following procedure for adjustment. Refer to figure 3‐1 for
locations of adjustments.

Manual Set Point Adjustment

To adjust the set point, open the controller cover and move the set point indicator until the indicator is at the desired
value on the process differential pressure scale. Move the adjustment indicator to the right to increase the set point
and to the left to decrease it. Adjusting the set point does not affect the proportional band setting.

If the controller is equipped with the optional external or internal set point adjustment, turn the adjustment knob
clockwise to increase the process set point and counterclockwise to decrease the process set point.

Remote Set Point (suffix letter M) Adjustment

CAUTION

Do not manually move the set point indicator on a controller with remote set point. Doing so could damage the controller.

If the controller is equipped with the remote set point option, vary the remote set point pressure to change the set
point. Increase the pressure to increase the set point and decrease the pressure to decrease the set point.

Proportional Band Adjustment (PB ADJ)

Locate the proportional band adjustment. Rotate the adjustment until the desired value is beneath the PB ADJ white
indicator mark. Adjusting the proportional band has a minimal effect on the set point.

Changing Controller Action

Switch controller action from direct to reverse or vice‐versa by simply loosening the screws on the proportional band
indicator cover and pulling the cover outward so the proportional band adjustment can be rotated to the desired
action (figure 5‐2).

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The white portion of the adjustment produces direct controller action. The black portion produces reverse controller
action.

After changing the action, tighten the screws on the proportional band indicator cover.

4194HA, HB, HC Controllers

September 2014

Reset (suffix letter B) Adjustment

Locate the reset adjustment. Rotate the adjustment clockwise to decrease the minutes per repeat or counterclockwise
to increase the minutes per repeat. Increasing the minutes per repeat provides a slower reset action.

Rate (suffix letter C) Adjustment

Locate the rate adjustment. Rotate the adjustment clockwise to decrease the minutes (faster rate action) or
counterclockwise to increase the minutes (slower rate action).

Anti‐Reset Windup (suffix letter F) Adjustment

If the arrow on the relief valve points toward the top of the controller case, as shown in figure 3‐1, the valve opens
when output pressure falls. If the arrow points in the opposite direction, the valve opens when output pressure rises.
Turn the adjusting screw counterclockwise to increase differential relief pressure; clockwise to decrease it. Differential
relief pressure is factory set at 0.3 bar (5 psi). Maximum differential relief pressure is 0.5 bar (7 psi). The minimum is 0.1
bar (2 psi).

Switching the Auto/Manual Station (suffix letter E)

Note

Switching the controller between automatic and manual mode without balancing can disturb the process and cause controller
cycling.

Refer to figure 6‐5 if the controller has the auto/manual station option.

Two balance methods are used to equalize the manual output pressure with the controller output pressure. To switch
from automatic to manual mode, carefully adjust the loader knob until the metal ball inside the plastic tube moves
into the switching zone. Then move the automatic/manual switch to MANUAL. Turn the loader knob clockwise to
increase the controller output or counterclockwise to decrease it.

To switch from manual to automatic mode, slide the set point indicator to move the ball into the switching zone. Turn
the switch to AUTO and move the set point indicator to control the output.

When the automatic/manual switch is in AUTO, adjusting the loader knob has no effect on the controller output.
When the automatic/manual switch is in MANUAL, changing the set point adjustment has no effect on the controller
output.

Prestartup Checks for 4194HB and HC Controllers

Refer to figure 3‐1 for location of adjustments and to figure 6‐1 for location of key numbers.

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When performing the checks, open loop conditions must exist. An open loop exists when the controller output does
not affect the input pressure or other control signal to the controller.

Note

If the controller has the auto/manual option (suffix letter E), be sure the controller is in the automatic mode before performing
prestartup checks. If the controller has the external feedback option, connect the controller output connection to the external
feedback connection (figure 2‐2). Disconnect after completing the prestartup checks.

1. Provide a means of measuring the controller output pressure by connecting the controller output to a pressure
gauge. Connect supply pressure to the supply pressure regulator and be sure it is delivering the proper supply
pressure to the controller. Do not exceed the normal operating pressure in table 1‐4.

2. For a controller with remote set point (suffix letter M), connect regulated pressure of 0.2 to 1.0 bar or 0.4 to 2.1 bar
(3 to 15 psig or 6 to 30 psig) to the remote set point connection at the top of the controller case.

3. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36).

4. Adjust the set point a minimum of 20 percent of input span above the process indicator.

5. Turn the reset adjustment to 0.01 minutes per repeat.

6. Turn the rate adjustment to OFF.

7. Adjust the proportional band knob to 5 percent DIRECT (direct action).

8. If necessary, connect a pressure source to the differential pressure unit and adjust the process indicator to the last
scale mark on the left side of the scale. If the last scale mark is 0 psig, a pressure source is not required.

9. The controller output pressure should be 0 psig.

10. Rotate the proportional band to 5 percent REVERSE (reverse action).

11. The controller output should be within 0.14 bar (2 psig) of the supply pressure.

12. If the controller output is within tolerance, adjust the proportional band adjustment to 400 percent in the desired
action, secure the proportional band indicator cover (key 36) with the two machine screws (key 6), and go to the
startup procedure. If the controller output pressure is not within tolerance, go to the calibration procedure for
4194HB and HC controllers for recalibration.

Startup for 4194HB and HC Controllers

Calibrate the controller prior to this procedure.

Note

When performing the startup procedure, keep in mind the initial settings are guidelines. They will vary depending on the actual
process being controlled.

1. Be sure the supply pressure regulator is delivering the proper supply pressure to the controller.

2. Move the set point adjustment to the desired set point.

3. Set the reset adjustment to 0.05 minutes per repeat for fast processes. Set it to 0.5 minutes per repeat for slow

processes. For controllers with rate, set the rate adjustment to OFF.

4. Set the proportional band adjustment to 100 percent for fast processes. For slow processes, calculate the

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Instruction Manual

D200156X012

proportional band percentage from the equation below:

4194HA, HB, HC Controllers

September 2014

Proportional
Band
Adjustment

For example:

5. If the controller is used with a control valve, return the control valve to service by slowly opening the upstream and
downstream manual control valves in the pipeline. Close the manual bypass valve, if one is used.

6. Tune the various controller actions.

D Tuning proportional action: Create a load upset by momentarily changing the set point. Check for system

cycling. If the system does not cycle, lower the proportional band setting (thus raising the gain) and disturb the
system again by changing the set point. Continue this procedure until the system cycles. At this point, double
the proportional band setting (proportional band setting X 2).

D Tuning reset action: Disturb the system. If the system does not cycle then speed up the reset by changing the

setting to a lower value (faster reset) and disturb the system again. Continue this procedure until the system
cycles. When the system cycles, multiply the reset time setting by a factor of three (reset time 3) and slow down
the reset by changing the setting to the higher value. The reset is now tuned.

D Tuning rate action: For a controller with rate (4194HC controllers), adjust the rate toward the lowest setting until

cycling occurs. When the system cycles, multiply the rate value by a factor of three (reset time X 3) and slow
down the rate by changing the setting to the higher value. The rate is now tuned.

7. Check the stability of the recommended proportional band setting by introducing a disturbance and monitoring
the process.

8. Once stable control is attained, the process indicator and set point adjustment indicator should be in line. If they are
aligned, return the set point to the desired value. If they are not, readjust the set point to the desired control point
on the process scale and proceed with step 9.

9. If the process indicator is within ±5 percent of the set point indicator, turn the link 3 adjustment (see figure 5‐3 for
location) until the process indicator aligns with the set point indicator. Turn the link 3 adjustment screw clockwise
to increase the process indication or counterclockwise to decrease it. If the process indicator is misaligned with the
set point adjustment by more than ±5 percent of the scale span, perform the calibration procedure for 4194HB and
HC controllers.

200 AllowableOvershoot

+

PressureSpan

200 2Psig

30Psig

^ 13%

Calibration for 4194HB and HC Controllers

WARNING

To avoid personal injury or property damage resulting from the sudden release of pressure, do not exceed the operating
limits given in this manual.

General Calibration Instructions

Note

If the controller has the auto/manual option, be sure the controller is in the automatic mode before performing calibration.

25

4194HA, HB, HC Controllers

September 2014

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D200156X012

If the prestartup checks or startup reveal faulty controller operation, perform the calibration described in this section.
These instructions are valid for either shop or field calibration, if open process loop conditions exist.

Unless otherwise noted, key numbers refer to figure 6‐1.

Process Indicator Zero‐and‐Span Calibration

Provide a regulated process differential pressure to the differential pressure unit. Also, plug the controller output
connection and provide a regulated supply pressure to the controller. Do not exceed the normal operating pressure in
table 1‐4.

Refer to figure 3‐1 for location of adjustments.

Note

Any adjustment of the process indicator span adjustment screw requires readjustment of the process indicator zero adjustment
screw.

1. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36).

2. Set the proportional band adjustment between DIRECT and REVERSE.

3. Adjust the process differential pressure until the input to the differential pressure unit is equal to the lowest limit of
the scale range.

4. If necessary, adjust the process indicator to the lowest limit of the process scale by loosening the zero adjustment
locking screw and turning the zero adjustment screw.

5. Adjust the process differential pressure until the input to the differential pressure unit is equal to the highest limit of
the scale range.

6. Note whether the process indicator is above or below the upper limit of the process scale.

7. Adjust the process indicator span adjustment screw as follows: Clockwise to increase the span for a low indication;
counterclockwise to decrease the span for a high indication. Adjust the span adjustment screw to correct for
approximately one‐half the error.

8. Repeat steps 3 through 7 until the error is eliminated.

9. Adjust the process differential pressure until the input to the differential pressure unit is equal to 50 percent of the
process scale range. The process indicator should point to the 50 percent process scale mark within ±2 percent of
span.

D If the error is greater than ±2 percent, perform the appropriate maintenance calibration procedure in the

Maintenance section.

D If the error is less than ±2 percent but more than ±1 percent, proceed with step 10.

10. Adjust the process indicator to within ±1 percent of the 50 percent scale mark by loosening the zero adjustment
locking screw and turning the zero adjustment screw. This distributes the error over the entire scale range and
brings all points within ±1 percent of the process input span.

11. Adjust the process differential pressure to 0 percent of the scale range.

12. The process indicator should indicate a zero scale reading, ±1 percent of the scale span.

13. Adjust the process differential pressure to 100 percent of the scale range.

14. The process indicator should point to the full scale reading, ±1 percent of the process scale span.

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Instruction Manual

D200156X012

4194HA, HB, HC Controllers

September 2014

15. If the error is greater than ±1 percent, repeat steps 3 through 14.

16. Perform the flapper alignment procedure.

Remote Set Point (suffix letter M) Zero‐and‐Span Calibration

Refer to figure 3‐1 for location of adjustments. Refer to figures 6‐1 and 6‐3 for key number locations.

Note

Any adjustment of the remote set point span adjustment screw will require readjustment of the set point zero adjustment screw.
See figure 3‐1.

Provide a regulated process differential pressure to the differential pressure unit. Also, plug the controller output
connection and provide a regulated supply pressure to the controller. Do not exceed the normal operating pressure in
table 1‐4.

1. Remove two screws (key 6) and lift off the proportional band indicator cover (key 36).

2. Set the proportional band adjustment between DIRECT and REVERSE.

3. Apply remote set point pressure equal to the low limit of the set point input range. Note the position of the set
point indicator. Loosen the set point zero adjustment locking screw and adjust the zero adjustment screw (figure
5‐6) until the set point indicator aligns with the lowest scale limit.

Properly align the set point indicator with the low scale limit. Tighten the zero adjustment locking screw.

4. Adjust the remote set point pressure to the upper limit of the input span. Note whether the indication is above or
below the upper limit of the process scale.

5. Adjust the span screw (figure 3‐1) as follows: Clockwise to increase span for a low indication; counterclockwise to
decrease span for a high indication. Adjust the span screw to correct one‐half the error.

6. Repeat steps 3 through 5 until the error is eliminated.

7. Adjust the remote set point pressure to 50 percent of the remote set point range.

8. Make sure the remote set point indicator is within ±2 percent of the mid‐scale mark, then proceed with step 9. If the
set point indicator is not within ±2 percent, proceed to the Remote Set Point Maintenance Calibration procedure in
Section 5.

9. Loosen the zero adjustment locking screw. Adjust the zero screw to correct for half the error.

10. Adjust the remote set point pressure to the lower and upper range limits. Make sure the set point indicator is within
±1 percent.

11. Install the proportional band indicator cover (key 36) and tighten two screws (key 6).

12. If necessary, proceed to the process indicator zero‐and‐span calibration procedure in this section. Otherwise,
proceed to the flapper alignment procedure in this section.

Flapper Alignment

Note

Perform the process indicator zero‐and‐span calibration procedure and, if necessary, the remote set point calibration procedure
before the flapper alignment.

If the controller has the external feedback option, connect the external feedback connection to the controller output connection.

27

4194HA, HB, HC Controllers

September 2014

Instruction Manual

D200156X012

Flapper leveling screw numbers and adjustments are shown in figure 3‐1.

Provide a regulated process differential pressure to the differential pressure unit. Also, plug the controller output
connection and provide a regulated supply pressure to the controller. Do not exceed the normal operating pressure in
table 1‐4.

Note

4194HB and HC controllers with the anti‐reset windup option (suffix letter F) are supplied with two O‐rings (key 52,
figure 6‐1/CONTROLLER COMMON PARTS), valve cover (key 51, figure 6‐1/VIEW E, 4194HB controllers or VIEW E, 4194HC
controllers), and two machine screws (key 53, figure 6‐1/VIEW E, 4194HB controllers or VIEW E, 4194HC controllers). Use these
parts in the next step.

1. For 4194HB and HC controllers with the anti‐reset windup option (suffix letter F), remove the differential relief valve
(key 55, figure 6‐1/VIEW E, 4194HB controllers, Option F or VIEW E, 4194HC controllers, Option F). Install the two
O‐rings (key 52) and valve cover (key 51) provided with the controller. Secure the valve cover over the two O‐rings
with the two machine screws (key 53) also provided.

2. For a controller with manual set point, move the set point indicator to 50 percent of the scale range. For a controller
with remote set point (suffix letter M), adjust the remote set point pressure until the set point indicator is at 50
percent of the scale range.

3. Remove the two machine screws (key 6) and lift off the proportional band indicator cover (key 36).

4. Adjust the reset adjustment to 0.01 minute per repeat.

5. If the controller has rate (4194HC controllers), turn the rate adjustment to OFF.

6. If the controller has the external feedback option (available with a 4194HB controller only), shut off the supply
pressure, connect the controller output to the external feedback connection, and turn on the supply pressure. See
figure 2‐2 for the location of the output and external feedback connections.

7. Adjust the process differential pressure to 50 percent of the input range. If pressure is not available to pressure the
differential pressure unit to 50 percent of range, an alternate method is to disconnect link 1 at the drive arm and
tape the process indicator at 50 percent of the process differential pressure input range.

Note

In steps 8 through 12, the controller output will not stabilize because of the high controller gain. The controller output gauge is
adequate to check the output pressure during this procedure.

8. Set the proportional band between DIRECT and REVERSE.

9. Adjust flapper leveling screw number 2 until the controller output is relatively stable at any value within the output
range.

10. Adjust the proportional band to 20 percent direct acting. Adjust flapper leveling screw number 3 until the controller
output is relatively stable at any value within the output range.

11. Adjust the proportional band to 20 percent reverse acting. Adjust flapper leveling screw number 1 until the
controller output is relatively stable at any value within the output range.

12. Repeat steps 8 through 11 until the controller output remains relatively stable with no adjustments of the flapper
leveling screws.

Note

Steps 13 through 19 check the flapper alignment.

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