Emerson Fisher 3660, Fisher 3661 Instruction Manual

Instruction Manual

D101402X012

Fisherr 3660 and 3661 Positioners

3660 and 3661 Positioners

January 2013

Contents

Introduction 2.................................

Scope of Manual 2.............................

Description 2.................................

Specifications 2...............................

Educational Services 2.........................

Installation 5..................................

Hazardous Area Classifications and Special

Instructions for “Safe Use” and Installation

in Hazardous Locations for 3661 Positioner 5....

CSA 5....................................

FM 6.....................................

ATEX 6...................................

IECEx 7...................................

Positioner Mounting 8.........................

Mounting on 1250, 1250R, 3024S

and GX Actuators 8......................

Mounting on Baumannt Actuators 12........

Mounting on 657 and 667 Actuators 13.......

Feedback Lever Assembly and

Range Spring Installation 16..................

Pressure Connections 19.......................

Supply Connection 19......................

Output Connection 21......................

Instrument Connection 21..................

Diagnostic Connections 21..................

Vent Connection 22...........................

Electrical Connections for 3661 Positioners 22.....

Calibration 23..................................

Split Range Operation 25.......................

3660 Bypass Operation 26.......................

Principle of Operation 27........................

Maintenance 28................................

Changing the Positioner Action 29...............

Changing the Range Spring 29..................

Changing the Input Signal Range on

3660 Positioners 29.........................

Removing the Positioner from the Actuator 29.....

Center‐Bolt Mounting on 1250, 1250R,

3024S and Baumann Actuators 29.........

Clamp Mounting on 1250, 1250R

and 3024S Actuators 30..................

Mounting Bracket/U‐Bolt Mounting on

657 and 667 Actuators 30................

Figure 1. Fisher 3660 Positioner Mounted on a
Baumann Actuator

W7174

Changing the Input Module

Diaphragm Assembly 30.....................

Disassembling and Assembling Relay

Components 31............................

Disassembling and Assembling the Bypass

Valve 32...................................

Replacing the 3661 Converter Module 33.........

Parts Ordering 33...............................

Parts Kits 34...................................

Repair Kits 34.................................

Mounting Kits 34..............................

Parts List 34...................................

Positioner Common Parts 34....................

Diagnostic Connections 39.....................

Mounting Parts 39.............................

Loop Schematics/Nameplates for

3661 Positioner 42.............................

www.Fisher.com

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Introduction

Scope of Manual

This instruction manual includes installation, operation, calibration, maintenance, and parts ordering information for
Fisher 3660 and 3661 positioners. Refer to separate instruction manuals for information on the actuator and control
valve.

Do not install, operate, or maintain a 3660 or 3661 positioner 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 of 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.

Description

3660 pneumatic and 3661 electro‐pneumatic, single‐acting positioners are used with Fisher 657, 667, 1250, 1250R,
3024S, and GX actuators. These positioners can also be mounted on Baumann actuators. Figure 1 shows a 3660
positioner mounted on a Baumann actuator.

The positioner mounts on the actuator and provides the desired plug position for a specific input signal. The 3660
positioner accepts a pneumatic signal and the 3661 accepts a 4 to 20 milliampere DC input signal.

Specifications

Specifications for the 3660 and 3661 positioners are shown in table 1.

Educational Services

For information on available courses for 3660 and 3661 positioners, as well as a variety of other products, contact:

Emerson Process Management
Educational Services, Registration
P.O. Box 190; 301 S. 1st Ave.
Marshalltown, IA 50158-2823
Phone: [phone] or
Phone: [phone]
FAX: [phone]
e‐mail: [e-mail]

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Instruction Manual

D101402X012

Table 1. Specifications

3660 and 3661 Positioners

January 2013

Available Configuration

3660: Single‐acting pneumatic valve positioner
3661: Single‐acting electro‐pneumatic valve

positioner

Input Signal

3660

J 0.2 to 1.0 bar
J 0.4 to 2.0 bar

(3 to 15 psig),
(6 to 30 psig), or

J split range (see tables 7 and 8)

3661:

J

4 to 20 mA DC constant current with 30 VDC

maximum compliance voltage.
J split range is also available, see tables 7 and 8

Equivalent Circuit (3661)

120 ohms shunted by three 5.6 V zener diodes

Output Signal

Type: Pneumatic pressure as required by the actuator
up to full supply pressure

Action:

J Direct (increasing input signal pressure increases
positioner output),
J Reverse (increasing input signal pressure
decreases positioner output)

Supply Pressure

(1)

Recommended: 10% above actuator requirements
Maximum: 6.2 bar (90 psig) or pressure rating of

actuator, whichever is lower

Medium: air

3660 and 3661 are not compatible with natural gas
as the supply medium

Performance

Independent Linearity: ±1% of output span
Hysteresis: 0.5% of output span

(2)

Deadband: 0.1% of input span
Electromagnetic Compatibility for 3661
electro‐pneumatic positioner:

Meets EN 61326‐1 (First Edition)
Immunity—Industrial locations per Table 2 of
the EN 61326‐1 standard. Performance is
shown in table 2 below.
Emissions—Class A
ISM equipment rating: Group 1, Class A

- continued -

Positioner Adjustments

Span: J Adjustable up to 20 mm (0.75 inch) stem
travel, or J Adjustable from 20 mm (0.75 inch) to 50
mm (2 inch) stem travel

Zero: 0 to 100%
Gain: 0.5 to 6% PB (proportional band)

(3)

Output Volume Damping: Loop dynamic response
adjustment

Delivery Capacity

(4)

1.4 Bar (20 Psig) Supply: 4.3 normal m3/hour
(150 scfh)

2.4 Bar (35 Psig) Supply: 6.6 normal m

3

/hour

(230 scfh)

Exhaust Capacity

(4)

1.4 Bar (20 Psig) Supply: 4.8 normal m3/hour
(170 scfh)

2.4 Bar (35 Psig) Supply: 7.4 normal m

3

/hour

(260 scfh)

Steady‐State Air Consumption

(4,5)

3660: 0.17 normal m3/hour (6.0 scfh) at 1.4 bar

3

(20 psig) supply pressure. 0.22 normal m
(7.9 scfh) at 2.4 bar (35 psig) supply pressure
3661: 0.24 normal m

3

/hour (8.8 scfh) at 1.4 bar

(20 psig) supply pressure. 0.33 normal m

/hour

3

/hour

(12.3 scfh) at 2.4 bar (35 psig) supply pressure

Operating Influence

Supply Pressure: 70 mbar (1 psig) change in supply
pressure changes the actuator stem position less than

(6)

0.16%

Operative Temperature Limits

of travel

(1)

3660 without Pressure Gauges: -40 to 121°C
(-40 to 250°F)
3660 with Pressure Gauges: -40 to 82°C
(-40 to 180°F)
3661 with or without Pressure Gauges: -40 to 82°C
(-40 to 180°F)

Hazardous Area Classification for 3660

3660 pneumatic positioners comply with the
requirements of ATEX Group II Category 2 Gas and
Dust

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3660 and 3661 Positioners

January 2013

Table 1. Specifications (Continued)

Instruction Manual

D101402X012

Hazardous Area Classification for 3661

CSA—Intrinsically Safe, Type n, Non‐incendive

Conduit Connection for 3661

1/2 NPT (M20 or PG13 adaptors, optional)

FM—Intrinsically Safe, Type n, Non‐incendive
ATEX—Intrinsically Safe, Type n

(Gas Atmospheres Only)
IECEx—Intrinsically Safe, Type n

(Gas Atmospheres Only)

Maximum Valve Stem Travel

Two ranges:

J 50 mm (2 inch) to 20 mm (0.75 inch) minimum;
J 20 mm (0.75 inch) adjustable to lesser travel with

standard input signal
Refer to Hazardous Area Classifications and Special
Instructions for “Safe Use” and Installation in
Hazardous Locations, starting on page 5, for
additional information.

Housing Classification for 3661

CSA—Type 3 Encl.

Approximate Weight

3660: 1.2 kg (2.6 pounds)

3661: 1.4 kg (3.0 pounds)

Vent Connection

1/4 NPT internal

FM—NEMA 3, IP54
ATEX—IP44
IECEx—IP44

Mounting orientation requires vent location to be
below horizontal.

Other Classifications/Certifications for 3661

KGS—Korea Gas Safety Corporation

Mounting

The positioner can be mounted in one of four
different configurations. See figure 2 for mounting.

Pressure Connections

1/4 NPT internal

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

1. The pressure/temperature limits in this manual and any applicable standard or code limitation should not be exceeded.

2. Hysteresis value at a gain setting of 1/2 turn.

3. Adjusting the gain (PB) adjustment changes the nozzle flapper relationship. This nozzle flapper change affects the actuator/positioner response time.

4. Normal m

5. Air consumption at a gain setting of 1/2 turn.

6. At supply pressure of 2.4 bar (35 psig).

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).

Options

3660: J Instrument and output pressure gauges,

J Integrally mounted bypass valve

3661: Output pressure gauge

Declaration of SEP

Fisher Controls International LLC declares this

product to be in compliance with Article 3 paragraph

3 of the Pressure Equipment Directive (PED) 97 / 23 /

EC. It was designed and manufactured in accordance

with Sound Engineering Practice (SEP) and cannot

bear the CE marking related to PED compliance.

However, the product may bear the CE marking to

indicate compliance with other applicable European

Community Directives.

Table 2. Fisher 3661 Positioner EMC Summary Results—Immunity

Port Phenomenon Basic Standard Test Level

Electrostatic discharge (ESD) IEC 61000‐4‐2

Enclosure

I/O

signal/control

Specification limit = ±1% of span

1. A = No degradation during testing. B = Temporary degradation during testing, but is self‐recovering.

4

Radiated EM field IEC 61000‐4‐3

Rated power frequency magnetic field IEC 61000‐4‐8 60 A/m at 50 Hz A
Burst IEC 61000‐4‐4 1 kV A
Surge IEC 61000‐4‐5 1 kV (line to ground only, each) B
Conducted RF IEC 61000‐4‐6 150 kHz to 80 MHz at 3 Vrms A

4 kV contact
8 kV air

80 to 1000 MHz @ 10V/m with 1 kHz AM at 80%
1400 to 2000 MHz @ 3V/m with 1 kHz AM at 80%
2000 to 2700 MHz @ 1V/m with 1 kHz AM at 80%

Performance

Criteria

A

A

(1)

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Installation

Typically, a positioner is shipped with the actuator. If so, the factory mounts and calibrates the positioner and connects
the positioner to actuator tubing. If the positioner is ordered separately from the actuator, perform the appropriate
mounting procedure. Refer to the appropriate instruction manuals for actuator and valve installation procedures.

WARNING

Always wear protective clothing, gloves, and eyewear when performing any Installation procedures to avoid personal
injury.

If installing into an existing application, also refer to the WARNING at the beginning of the Maintenance section in this
instruction manual.

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

Hazardous Area Classifications and Special Instructions for “Safe Use” and
Installation in Hazardous Locations for 3661 Positioner

Certain nameplates may carry more than one approval, and each approval may have unique installation/wiring
requirements and/or conditions of “safe use”. These special instructions for “safe use” are in addition to, and may
override, the standard installation procedures. Special instructions are listed by approval.

Note

This information supplements the nameplate markings affixed to the product.

Always refer to the nameplate itself to identify the appropriate certification.

WARNING

Failure to follow these conditions of “safe use” could result in personal injury or property damage from fire or explosion,
and area re‐classification.

CSA

Special Conditions of Safe Use

Intrinsically Safe and Non‐incendive

No special conditions for safe use.

Type n

Type n installations must be in a suitable (IP5X) enclosure.

Refer to table 3 for additional approval information, figure 27 for CSA loop schematics, and figure 28 for a typical
CSA/FM approval nameplate.

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January 2013

Instruction Manual

D101402X012

Table 3. Hazardous Area Classifications for Fisher 3661 Positioner—CSA (Canada)

Certification

Body

CSA

Intrinsically Safe
Ex ia IIC T4/T5/T6 per drawing GE28591
Class I, II Division 1 GP A,B,C,D,E,F,G
T4/T5/T6 per drawing GE28591

Type n
Ex nA IIC T6

Class I Division 2 GP A,B,C,D T6 - - - T6 (Tamb ≤ 82°C) CSA Type 3 Encl.

Certification Obtained Entity Rating Temperature Code Enclosure Rating

Vmax = 30 VDC
Imax = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH

- - - T6 (Tamb ≤ 82°C) CSA Type 3 Encl.

T4 (Tamb ≤ 82°C)
T5 (Tamb ≤ 62°C)
T6 (Tamb ≤ 47°C)

CSA Type 3 Encl.

FM

Intrinsically Safe, Type n, and Non‐incendive

No special conditions for safe use.

Refer to table 4 for approval information, figure 29 for the FM loop schematic, and figure 28 for a typical CSA/FM
approval nameplate.

Table 4. Hazardous Area Classifications for Fisher 3661 Positioner—FM (United States)

Certification

Body

FM

Intrinsically Safe
Class I Zone 0 AEx ia IIC T4/T5/T6 per drawing
GE28590
Class I, II, III Division 1 GP A,B,C,D,E,F,G
T4/T5/T6 per drawing GE28590

Type n
Class I Zone 2 AEx nA IIC T5

Class I Division 2, GP A,B,C,D T5
Class II, III Division 2, GP F,G T5

Certification Obtained Entity Rating Temperature Code Enclosure Rating

Vmax = 30 VDC
Imax = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH

- - - T5 (Tamb ≤ 82°C) NEMA 3, IP54

- - - T5 (Tamb ≤ 82°C) NEMA 3, IP54

T4 (Tamb ≤ 82°C)
T5 (Tamb ≤ 62°C)
T6 (Tamb ≤ 47°C)

NEMA 3, IP54

ATEX

Special Conditions for Safe Use

Intrinsically Safe

This equipment is intrinsically safe and can be used in potentially explosive atmospheres.

The electrical parameters of certified equipment which can be connected to the device must not exceed the following
value: U

Ambient Temperature:
T6, at Tamb = 47_C
T5, at Tamb = 62_C
T4, at Tamb = 71_C

6

30 Vdc; I

≤

0

150 mA; P

≤

0

1.25 W.

≤

0

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Type n

The 3661 has an IP44 ingress protection: it is only intended to be installed in an area where a convenient protection is
ensured against the entry of solid foreign bodies and liquids which may decrease the safety.

Refer to table 5 for additional approval information and figure 30 for a typical ATEX/IECEx approval nameplate.

Table 5. Hazardous Area Classifications for Fisher 3661 Positioner—ATEX

Certificate Certification Obtained Entity Rating Temperature Code Enclosure Rating

Ui = 30 VDC
Ii = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH

T4 (Tamb ≤ 82°C)
T5 (Tamb ≤ 62°C)
T6 (Tamb ≤ 47°C)

- - - T6 (Tamb ≤ 82°C) IP44

IP44

ATEX

II 1 G
Intrinsically Safe
Gas
Ex ia IIC T4/T5/T6

II 3 G
Type n
Gas
Ex nA IIC T6

IECEx

Conditions of Certification

Intrinsically Safe

WARNING

Substitution of components may impair intrinsic safety.

-40_C Ta +82_C; T6 (Ta +47_C); T5 (Ta +62_C)

Entity Parameters

= 30 V, li = 150 mA, Pi = 1.25 W, Ci = 0 nF, Li = 0 mH

Ui

Type n

WARNING

Disconnect power before opening.

-40_C Ta +82_C; T6 (Ta +82_C)

Refer to table 6 for additional approval information, and figure 30 for a typical ATEX/IECEx approval nameplate.

Table 6. Hazardous Area Classifications for Fisher 3661 Positioner—IECEx

Certificate Certification Obtained Entity Rating Temperature Code Enclosure Rating

IECEx

Intrinsically Safe
Gas
Ex ia IIC T4/T5/T6

Type n
Gas
Ex nA IIC T6

Ui = 30 VDC
Ii = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH

- - - T6 (Tamb ≤ 82°C) IP44

T4 (Tamb ≤ 82°C)
T5 (Tamb ≤ 62°C)
T6 (Tamb ≤ 47°C)

IP44

7

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Positioner Mounting

Mounting on 1250, 1250R, 3024S, and GX Actuators

During the following mounting procedures, refer to figures 3, 24, and 25 for key number locations.

Figure 3 shows keys 64 through 78 and 101 through 104. Other key numbers are shown in either figure 24 for the
3660 positioner or figure 25 for the 3661 positioner. Two mounting methods are available, center‐bolt mounting and
clamp mounting.

1. Determine the positioner mounting configuration from figure 2. The actuator size, actuator travel, and positioner
action must be known. If center‐bolt mounting is desired, be certain the actuator is equipped with tapped holes in
the posts.

2. Thread the hex head screws with washers (keys 69 and 70) several turns into the stem connector. The feedback
plate (key 68) is reversible and must be positioned so that the pilot shaft (key 19A) will operate correctly in the slot
of the feedback plate. For actuator travels between 20 and 30 mm (0.787 and 1.18 inches) (for 3024S actuators,
travel ranges between 16 and 32 mm), position the feedback plate so the long portion of its slot, when bolted to
the stem connector, is closest to the positioner as shown in figure 4. For travels greater than 30 mm (1.18 inches),
reverse the position of the feedback plate as shown in figure 4.

a. For size 30 and 34 actuators with all travels and for size 45 actuators with travel greater than 30 mm (1.18

inches), position the feedback plate (key 68) between the stem connector and washers and tighten the hex head
screws (key 69).

b. For size 45 actuators with travel between 20 and 30 mm (0.787 and 1.18 inches) (16 and 32 mm for 3024S

actuators), attach the feedback adaptor (key 103) to the feedback plate (key 68) using machine screws,
lockwashers, and wedge nuts (keys 102, 101, and 104). The feedback plate and the wedge nuts must be
assembled as shown in the lower right portion of figure 3. Use the mounting holes in the feedback adaptor and
position it as indicated in figure 4. Then, position the feedback plate between the stem connector and washers
and tighten the hex head screws (key 69).

3. Unscrew the two machine screws (key 24), and remove the positioner cover (key 21).

Center‐Bolt Mounting (GX Actuator)

a. As shown in figure 5, a thin knockout section is cast across the mounting hole in the housing. Check to make

certain this knockout section has been removed. If the knockout section has not been removed, use a punch to
knock it out.

b. Attach the positioner to the actuator using a sealing washer and hex head screw (keys 71 and 72).

c. Install the feedback lever assembly and range spring.

Clamp Mounting

a. Install a hex nut (key 66) on one end of each of two studs (key 65). Turn the nuts all the way to the end of the

threads.

b. Thread the end of each stud (key 65), (the end with hex nut—key 66), into the back of the positioner housing

(key 1) as far as the studs will go. Tighten both nuts against the housing.

c. Set the actuator at mid‐travel using a manual loading regulator.

d. With the finger end of the bracket (key 64) toward the positioner pressure connections as shown in figure 3,

place the bracket and washers (key 67) over the studs (key 65). Thread the hex nuts (key 66) several turns onto
the studs.

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Instruction Manual

D101402X012

Figure 2. Mounting Configurations

Input Signal Positioner Output

Direct

0.2 to 1.0 bar (3 to 15 psig)

0.4 to 2.0 bar (6 to 30 psig)
4 to 20 mA

Reverse

1.0 to 0.2 bar (15 to 3 psig)

2.0 to 0.4 bar (30 to 6 psig)
20 to 4 mA

For split range signal refer to tables 7 and 8

3660 and 3661 Positioners

January 2013

Up to 6.2 bar (90 psig)

OUTPUT

AIR SUPPLY

2

PILOT SHAFT

1

INPUT SIGNAL

FEEDBACK
PLATE

ACTUATOR: AIR‐TO‐RETRACT
POSITIONER ACTION: DIRECT
(INCREASING INPUT SIGNAL INCREASES
OUTPUT PRESSURE TO ACTUATOR)

ACTUATOR: AIR‐TO‐RETRACT
POSITIONER ACTION: REVERSE
(INCREASING INPUT SIGNAL DECREASES
OUTPUT PRESSURE TO ACTUATOR)

OUTPUT

AIR SUPPLY

1

2

INPUT SIGNAL

ACTUATOR: AIR‐TO‐EXTEND
POSITIONER ACTION: REVERSE
(INCREASING INPUT SIGNAL DECREASES
OUTPUT PRESSURE TO ACTUATOR)

NOTES:
1 WHEN MOUNTING ON BAUMANN ACTUATORS, INSTALL FEEDBACK PLATE SO LIP IS UP. INSTALL FEEDBACK LEVER ARM
ASSEMBLY, PRELOADED, SO PILOT SHAFT IS ON TOP OF THE FEEDBACK PLATE.
2 WHEN MOUNTING ON BAUMANN ACTUATORS, INSTALL FEEDBACK PLATE SO LIP IS DOWN. INSTALL FEEDBACK LEVER ARM
ASSEMBLY, PRELOADED, SO PILOT SHAFT IS UNDERNEATH THE FEEDBACK PLATE.

17B9106‐B
17B9105‐B
38B0195‐B
A4035‐2

ACTUATOR: AIR‐TO‐EXTEND
POSITIONER ACTION: DIRECT
(INCREASING INPUT SIGNAL INCREASES
OUTPUT PRESSURE TO ACTUATOR)

OUTPUT

INPUT SIGNAL

AIR SUPPLY

OUTPUT

INPUT SIGNAL

AIR SUPPLY

9

3660 and 3661 Positioners

January 2013

Figure 3. Positioner Mounting on Fisher 1250, 1250R, and 3024S Actuators

NIPPLE MOUNTED

FILTER REGULATOR

Instruction Manual

D101402X012

CENTER BOLT

MOUNT

41B3946‐F

CLAMP MOUNT

SECTION A‐A

WEDGE NUT
(KEY 104)

LOCKWASHER
(K3Y 101)

FILTER

A

A

REGULATOR

FEEDBACK
PLATE
(KEY 68)

MACHINE
SCREW
(KEY 102)

FEEDBACK
ADAPTOR
(KEY 103)

FEEDBACK
LEVER
ASSEMBLY

SIZE 45 WITH TRAVEL BETWEEN

20 AND 30 mm (0.787 AND 1.18 INCHES)

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Instruction Manual

D101402X012

3660 and 3661 Positioners

Figure 4. Feedback Plate Orientation with Positioner Mounted on Fisher 1250, 1250R, and 3024S Actuators

January 2013

POSITIONER

ACTUATOR LEG

PILOT SHAFT

STEM CONNECTOR

FEEDBACK
PLATE

FEEDBACK LEVER
ASSEMBLY

FOR SIZE 30 AND 34 ACTUATORS WITH TRAVEL

BETWEEN 20 AND 30 mm (0.787 AND 1.18 INCHES)

ACTUATOR STEM

FEEDBACK
ADAPTOR

POSITIONER

ACTUATOR LEG

FEEDBACK LEVER
ASSEMBLY

PILOT SHAFT

STEM CONNECTOR

FOR SIZE 30,34 AND 45 ACTUATORS WITH

TRAVEL GREATER THAN 30mm (1.18 INCHES)

STEM CONNECTOR

FEEDBACK
PLATE

FEEDBACK
PLATE

USE THESE HOLES
WHEN MOUNTING

B2260‐1

THE FEEDBACK
ADAPTOR TO THE
FEEDBACK PLATE

FOR SIZE 45 ACTUATORS WITH TRAVEL BETWEEN

20 AND 30 mm (0.787 AND 1.18 INCHES)

VALVE STEM

Note

Do not install the range spring in the following step. Feedback lever assembly (key 19) installation in the next step is only
temporary to permit verifying alignment.

e. Install the positioner on the actuator by placing the bracket (key 64) around the appropriate actuator leg.

Visually center the center line of the slot in the feedback plate (key 68) with the center line of the hole in the
housing. Then, tighten the nuts (key 66) only tight enough to prevent the positioner from moving on the
actuator leg. Locate the feedback lever assembly (key 19) so that it may be temporarily installed into the
positioner housing (key 1) and the feedback plate (key 68) to verify alignment. Do not install the range spring at
this time. Place the pilot shaft (key 19A) in the slot of the feedback plate, and, at the same time, insert the
feedback shaft in the hole of the positioner housing. Depress the feedback lever assembly inward until it stops
against the housing. Make certain the slots in both the feedback lever assembly and the feedback plate are
horizontal with each other and that the feedback lever assembly and the feedback plate are parallel with each

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3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

other. If necessary, correct alignment by loosening the hex nuts (key 66) and moving the positioner on the
actuator leg as required.

f. Tighten the two hex nuts (key 66) to secure the positioner to the actuator leg.

g. Install the feedback lever assembly and range spring.

Mounting on Baumann Actuators

During the following mounting procedures, refer to figures 2, 5, 6, 24, and 25. Key numbers are shown in either figure
24 for the 3660 positioner or figure 25 for the 3661 positioner.

Figure 5. Actuator Center‐Bolt Mounting

Figure 6. Feedback Plate Installation for Baumann
Actuators

A4949‐1

THIN SECTION

ACTUATOR
STEM

VALVE
STEM

1 IF AFTER MOUNTING POSITIONER, THE FEEDBACK LEVER ARM ASSEMBLY WILL BE ON
THE LEFT SIDE OF THE POSITIONER, INSTALL THE FEEDBACK PLATE SO THE LIP IS UP.
INSTALL THE FEEDBACK LEVER ARM ASSEMBLY, PRELOADED, SO THE PILOT SHAFT IS
ABOVE THE PLATE. IF AFTER MOUNTING POSITIONER, THE FEEDBACK LEVER ARM
ASSEMBLY WILL BE ON THE RIGHT SIDE OF THE POSITIONER, INSTALL THE FEEDBACK PLATE
SO THE LIP IS DOWN. INSTALL THE FEEDBACK LEVER ARM ASSEMBLY, PRELOADED, SO THE
PILOT SHAFT IS BELOW THE PLATE.

A7223

PILOT SHAFT

FEEDBACK LEVER
ARM ASSEMBLY

1

FEEDBACK
PLATE

1. Determine the positioner mounting configuration from figure 2. The actuator size, actuator travel, and positioner
action must be known.

2. Attach the feedback plate to the actuator stem connector by locating the feedback plate between the actuator
stem and valve stem nuts (figure 6) as follows:

D If after the positioner is mounted the feedback lever assembly will be on the left side of the positioner, install the

feedback plate so the lip is up.

D If after the positioner is mounted the feedback lever assembly will be on the right side of the positioner, install

the feedback plate so the lip is down.

3. Unscrew the two machine screws (key 24), and remove the positioner cover (key 21).

4. As shown in figure 5, a thin knockout section is cast across the mounting hole in the housing. Check to make certain
this knockout section has been removed. If the knockout section has not been removed, use a punch to knock it
out.

5. For air to extend actuators, the feedback lever assembly must be installed into the positioner and preloaded before
attaching the positioner to the actuator.

6. Attach the positioner to the actuator using a sealing washer and hex head screw (keys 71 and 72).

7. Install the feedback lever assembly and range spring.

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Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Mounting on 657 and 667 Actuators

During the following mounting procedures, refer to figures 7, 24, and 25 for key number locations. Figure 7 shows
keys 69 and 70, 73 through 78, and 82 through 93. Other key numbers are shown in either figure 24 for the 3660
positioner or figure 25 for the 3661 positioner.

1. Determine the positioner mounting configuration from figure 2. The actuator size, actuator travel, and positioner
action must be known.

Note

The actuator bench set spring load must be released before removing the stem connector cap screws. Refer to the appropriate
actuator instruction manual for this procedure. After installing the positioner and mounting hardware, reset the actuator bench
set.

2. Attach the connector bracket (key 87) to the actuator stem connector using washers and cap screws (keys 70
and 69), but do not tighten the screws. Refer to figures 7 and 8 for the proper orientation of the connector bracket
with respect to the actuator stem connector. The face of the stem connector should be perpendicular to the legs of
the actuator yoke.

3. Refer to figure 8 for the feedback arm (key 88) location with respect to the connector bracket (key 87). Position the
feedback arm so that the pilot shaft (key 19A) will operate correctly in the slot of the feedback arm. For actuator
travels between 19 and 30 mm (0.75 and 1.18 inches), position the feedback arm so that the long portion of the
feedback arm slot, when fastened to the connector bracket, is closest to the positioner (see figure 8). For travels
greater than 30 mm (1.18 inches) reverse the feedback arm so the slot in the feedback arm is opposite the
positioner (see figure 8).

4. Attach the feedback arm (key 88) to the connector bracket (key 87) using machine screws, washers and hex nuts
(keys 91, 92 and 93), but do not tighten the hex nuts.

5. Unscrew the two machine screws (key 24), and remove the positioner cover (key 21).

6. As shown in figure 5, a thin knockout section is cast across the mounting hole in the housing. Check to make certain
that this knockout section has been removed. If the knockout section has not been removed, use a punch to knock
it out.

7. Set the actuator at mid‐travel using a manual loading regulator.

8. Install the stud clamp (key 83) in the mounting bracket (key 82). Place the mounting bracket against the outside of
the actuator leg. Attach the two U‐bolts (key 84) and the mounting bracket to the actuator leg using washers and
hex nuts (key 85 and 86), but do not tighten the nuts. Depending on the positioner action, it may be necessary to
straddle the travel indicator scale located on the inside of the actuator leg.

Note

Do not install the range spring in the following step. Feedback lever assembly (key 19) installation in the next step is only
temporary to permit verifying alignment.

13

3660 and 3661 Positioners

January 2013

Figure 7. Positioner Mounting on Fisher 657 and 667 Actuators

FILTER
REGULATOR

667

Instruction Manual

D101402X012

TO POSITIONER
OUTPUT

A

A

APPLY LUB

41B6744‐D

14

NIPPLE MOUNTED

FILTER REGULATOR

SECTION A‐A

Instruction Manual

3660 and 3661 Positioners

D101402X012

Figure 8. Feedback Arm Orientation with Positioner Mounted on Fisher 657 and 667 Actuators

January 2013

PILOT SHAFT

B2256‐1

POSITIONER

ACTUATOR LEG

CONNECTOR

BRACKET
FEEDBACK
ARM

STEM CONNECTOR

ACTUATOR STEM

CONNECTOR
BRACKET

FEEDBACK
ARM

FEEDBACK LEVER
ASSEMBLY

SIZES 30 THROUGH 40 ACTUATORS WITH

TRAVEL UP TO 30 mm (1.18 INCHES)

POSITIONER
ACTUATOR LEG

CONNECTOR
BRACKET

FEEDBACK
LEVER ASSEMBLY

PILOT SHAFT

STEM CONNECTOR

ACTUATOR STEM

CONNECTOR
BRACKET

FEEDBACK
ARM

SIZES 30 THROUGH 40 ACTUATORS WITH

TRAVEL GREATER THAN 30 mm (1.18 INCHES)

VALVE STEM

VIEW A

VALVE STEM

VIEW B

PILOT SHAFT

POSITIONER

ACTUATOR LEG

CONNECTOR
BRACKET
FEEDBACK
ARM

STEM CONNECTOR
ACTUATOR STEM

SIZES 45 THROUGH 60 ACTUATORS WITH

TRAVEL UP TO 30 mm (1.18 INCHES)

POSITIONER

ACTUATOR LEG

CONNECTOR
BRACKET

FEEDBACK LEVER ASSEMBLY

PILOT SHAFT

FEEDBACK ARM

SIZES 45 THROUGH 60 ACTUATORS WITH

TRAVEL GREATER THAN 30 mm (1.18 INCHES)

A

A

FEEDBACK LEVER
ASSEMBLY

STEM
CONNECTOR

ACTUATOR STEM

B

B

9. Attach the positioner to the stud clamp (key 83) using the sealing washer and hex nut (keys 89 and 90), but do not
tighten the nut. Visually center the center line of the slot in the feedback arm (key 88) with the center line of the
hole in the housing. Then, tighten the nuts (keys 90 and 86) only tight enough to prevent the positioner and
mounting bracket from moving on the actuator leg. Locate the feedback lever assembly (key 19) so it may be
temporarily installed into the positioner housing (key 1) and the feedback arm (key 88) to verify alignment. Do not
install the range spring at this time. Place the pilot shaft (key 19A) in the slot of the feedback arm, and, at the same
time, insert the feedback shaft in the hole of the positioner housing. Depress the feedback lever assembly inward
until it stops against the housing. Make certain the slots in both the feedback lever assembly and feedback arm are
horizontal and that the feedback lever assembly and the feedback arm are parallel with each other. If necessary,
correct alignment by loosening the hex nuts (keys 86 and 90) and either moving the stud clamp in the mounting
bracket or moving the mounting bracket on the actuator leg.

10. Tighten the nuts that were not tightened in the previous steps.

a. Tighten the hex nut (key 90) to secure the positioner to the stud clamp (key 83).

b. Tighten the four hex nuts (key 86) to secure the mounting bracket (key 82) to the actuator leg.

15

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

c. Tighten the machine screws and hex nuts (key 91 and 93) to secure the feedback arm (key 88) to the connector

bracket (key 87).

d. Tighten the hex head screws (key 69) to secure the connector bracket (key 87) to the actuator stem connector.

11. Install the feedback lever assembly and range spring.

Feedback Lever Assembly and Range Spring Installation

Key numbers are shown in either figure 24 for the 3660 positioner or figure 25 for the 3661 positioner. Key numbers
for the feedback lever assembly are shown in figure 26.

CAUTION

The range spring (key 30) and feedback lever assembly (key 19) must be installed together. Installing the range spring after
the feedback lever assembly is installed may result in damage to the lever assembly (key 17) flexures.

1. Refer to figure 9. Loosen the retaining screw (key 19P) located in the positioner housing until it is fully retracted into
the housing.

2. On the feedback lever assembly (key 19), loosen the zero adjustment screw (key 19S) until it is fully retracted into
the clinch nut.

3. On the feedback lever assembly, loosen the hex nut (key 19D) so the pilot shaft (key 19A) moves freely in the slot.

CAUTION

In the next step, be sure the feedback spring (key 19N) hooks on the spring pin (key 19R) opposite the zero adjustment
screw. If the feedback spring does not hook on the spring pin correctly, the feedback spring may be damaged during
feedback lever assembly (key 19) installation.

4. Refer to figure 10. Verify that the feedback spring in the feedback lever assembly bushing is hooked on the end of
the spring pin opposite the zero adjustment screw.

Note

When installing the feedback lever assembly bushing, be sure the anti‐rotating slot aligns with the retaining screw (key 19P).

5. Position the feedback lever assembly (key 19) so that the pilot shaft (key 19A) will rest on the feedback plate or slide
into the slot of the feedback arm (key 88) after installation.

6. Be sure the anti‐rotating slot aligns with the retaining screw (key 19P), then install the feedback lever assembly
bushing partially into the positioner.

Slight tension on the feedback spring (key 19N) may be required to get the anti‐rotating slot to align with the
retaining screw.

CAUTION

The reason for partially sliding the feedback lever assembly (key 19) into the housing is to permit installing the range spring
(key 30) without damaging the lever assembly (key 17) flexures. Installing the range spring after the feedback lever
assembly is completely installed may damage the lever assembly flexures.

16

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Figure 9. Installing the Feedback Lever Assembly

Figure 10. Positioning Feedback Spring

(Key 19) on the Positioner

FEEDBACK SPRING MUST
HOOK AROUND SPRING
PIN END OPPOSITE THE
ZERO ADJUSTMENT
SCREW

FEEDBACK
SHAFT

FEEDBACK SPRING

ANTI‐ROTATING SLOT

RETAINING
SCREW
(KEY 19P)

W7367

ZERO
ADJUSTMENT

COVER

27B9999‐D
A7224

SPRING PIN

7. Tighten the retaining screw (key 19P) until the screw engages the anti‐rotating slot so that the bushing does not
rotate, but leave the screw loose enough so that the bushing can slide freely into the housing.

8. Refer to figures 11 and 12. Select the appropriate range spring (key 30) from tables 7 and 8. Place the range spring
in the positioner so that one end of the spring is fully in the lever assembly slot. Next, rotate the feedback lever
assembly so that:

D the other end of the range spring aligns with the slot in the feedback shaft, and

D the pilot shaft (key 19A) is either above or below the actuator feedback plate or engages the slot in the feedback

arm (key 88).

Note

The feedback lever assembly bushing will no longer slide freely in the housing after it is placed in the normal operating position
due to the side loading of the retaining screw (key 19P) on the anti‐rotating slot.

9. Center the range spring (key 30) in the lever assembly (key 17) and feedback shaft slots; then push the feedback
lever assembly bushing into the housing far enough so that the spring is retained without holding it.

17

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Figure 11. Range Spring Installation

FEEDBACK

W7366

SHAFT

LEVER
ASSEMBLY

Figure 12. Range Spring Alignment

STRAIGHT PORTION
OF SPRING

FEEDBACK
SHAFT

SECTION A

A5211

RANGE SPRING

SLOT

LEVER
ASSEMBLY

BOSS

CAUTION

Installation of the feedback lever assembly (key 19) prior to installation of the range spring (key 30) may result in damage
to the lever assembly (key 17) flexures. The range spring must be in place before pushing the feedback lever assembly
bushing fully into the positioner housing.

10. Ensure the range spring (key 30) is properly aligned as shown in figure 12, then, as shown in figure 13, place hands
on both sides of the positioner and press firmly until the feedback lever assembly bushing shoulder is against the
positioner housing (figure 14).

11. While holding the feedback lever assembly bushing securely against the housing, tighten the retaining screw (key
19P). The feedback lever assembly bushing should be tight against the positioner housing as shown in figure 14.

Figure 13. Pressing the Feedback Lever Assembly
Bushing into the Positioner

W7365

Figure 14. Feedback Lever Assembly in Operating
Position

BUSHING (AGAINST
POSITIONER
HOUSING)

ZERO ADJUST
(SELF‐LOCKING)

W7366

18

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

12. Move the pilot shaft (key 19A) to the approximate span position shown in table 8.

Note

To ensure proper positioner performance, make certain, after alignment and all tightening is completed, that there is clearance
between the face of the pilot shaft and the feedback arm.

13. Install the feedback lever assembly cover (key 19T) with cover screw (key 19U).

14. Verify the positioner action. Note the letters D and R on the flapper (key 10). If the letter D is nearest the
adjustment screw (key 18), the positioner is set for direct action. To change the positioner action, refer to the
Changing Positioner Action procedure in the Maintenance section. If the action is changed, complete the
Calibration section before putting the unit into operation.

15. Install the positioner cover (key 21) and secure with the two machine screws (key 24). Make certain the Fisher logo
reads correctly and the vent is pointing downward. Continue with the Pressure Connections section.

Pressure Connections

Installing a 3660 or 3661 positioner requires tubing and pressure fittings. The fittings, tubing, and mounting parts
required depend on the type number and optional equipment, such as filter/regulator and bypass valve. See figure 15
for the location of the positioner pressure connections.

WARNING

The positioner is capable of providing full supply pressure to connected equipment. To avoid personal injury and property
damage caused by parts bursting from system overpressure, make sure the supply pressure never exceeds the maximum
safe working pressure of any connected equipment.

Supply Connection

WARNING

Severe personal injury or property damage may occur if the instrument air supply is not clean, dry and oil‐free. While use
and regular maintenance of a filter that removes particles larger than 40 micrometers 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 air or if you are unsure about the proper amount or method of air filtration or filter maintenance.

CAUTION

The O‐rings used in 3660 and 3661 positioners are made of EPDM (ethylene propylene). Use a clean, dry, oil‐free air supply
with instruments containing EPDM components. EPDM is subject to degradation when exposed to petroleum‐based
lubricants.

19

3660 and 3661 Positioners

January 2013

Figure 15. Typical Mounting Dimensions and Connections

ACTUATOR CENTERLINE TO POSITIONER

Type Size

30

657/667

1250

3024S

Baumann

GX

34

40
45/46
50/60

30

34

45

1.21

1.31

1.41

16in
32in
54in
70in

225
750

1200

2
2
2
2

Dimension X

mm Inch

92.2

95.3

104.9

108.0

128.5

86.0

86.0

110.0

83.5

87.5

87.5

53.8

71.4

71.4

71.4

81.0

81.0

81.0

3.63

3.75

4.13

4.25

5.06

3.39

3.39

4.33

3.29

3.44

3.44

2.12

2.81

2.81

2.81

3.19

3.19

3.19

Instruction Manual

D101402X012

31B3959‐C
C0686‐3

34.32

(1.35)

34.32
(1.35)

49.2

(1.94)

49.2

(1.94)

ACTUATOR POST CENTERLINE

191.2

(7.53)

93

(3.66)

ACTUATOR POST
CENTERLINE

142.2
(5.60)

93

(3.66)

49

(1.93)

122.3
(4.81)

122.3

(4.81)

67.5

(2.66)

0.5

(.02)

67.5

(2.66)

27.5

(1.08)

1/2 NPT
3661 I/P ONLY

DIM X

1/4 NPT
SUPPLY
CONNECTION

30

(1.18)

30

(1.18)

21.5

(.85)

1/4 NPT
INSTRUMENT
CONNECTION

DIM X

1/4 NPT
SUPPLY
CONNECTION

30

(1.18)

30

(1.18)

21.5
(.85)

1/4 NPT
INSTRUMENT
CONNECTION

ACTUATOR
CENTERLINE

1/4 NPT
OUTPUT
CONNECTION

ACTUATOR
CENTERLINE

1/4 NPT
OUTPUT
CONNECTION

mm

(INCH)

20

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Connect a clean, dry, oil‐free air source to the supply connection of the positioner. Use 3/8‐inch tubing or 1/4 NPT pipe
for the supply line. A supply air filter or a filter regulator capable of removing particles 40 micrometers in diameter is
recommended. The supply pressure should not exceed the following limits:

1. For the positioner, do not exceed the maximum pressure rating of 6.2 bar (90 psig).

2. For actuator pressure, refer to the appropriate actuator instruction manual for maximum allowable pressures.

3. For the valve body assembly, do not exceed the maximum allowable thrust of the specific valve.

Output Connection

Connect the OUTPUT connection to the actuator diaphragm casing connection. Use 3/8‐inch, 1/4‐inch, or 6 mm
tubing, or 1/4 NPT pipe between the actuator and the positioner.

Instrument Connection

Connect the control device output to the positioner INSTRUMENT connection. Use 3/8‐inch tubing to 1/4 NPT pipe.

The 3661 electro‐pneumatic positioner requires a 4-20 milliampere DC current input signal from the control device.
For connections to the 3661, refer to the Electrical Connections for 3661 Positioners section.

Diagnostic Connections

To support diagnostic testing of valve/actuator/positioner packages, special connectors and hardware are available.
Typical connector installations are shown in figure 16. The hardware used includes 1/4 NPT pipe nipples and pipe tees
with 1/8 NPT pipe bushings for the connectors. The connectors consist of 1/8 NPT bodies and body protectors. If the
diagnostic connectors are ordered for a positioner with gauges, 1/8‐inch stems are also included.

Figure 16. FlowScannert Valve Diagnostic System Connections

BODY PROTECTOR

BODY

4 INCH LONG
PIPE NIPPLE

GAUGE

STEM
PROVIDED WHEN
GAUGE IS SPECIFIED

PIPE BUSHING

PIPE TEE

1 INCH LONG PIPE NIPPLE

12B8052‐A
A6084

NOTE:
1 PIPE TEE, NIPPLE, BUSHING, BODY AND PROTECTOR NOT REQUIRED
FOR THE 3661 POSITIONER

21

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Install the connectors and hardware between the 3660 or 3661 positioner and the actuator.

1. Before assembling the pipe nipple, pipe tee, pipe bushings, actuator piping, and connector body, apply sealant to
all threads. Sealant is provided with the diagnostic connectors and hardware.

2. Turn the pipe tee to position the connector body and body protector for easy access when doing the diagnostic
testing.

Vent Connection

3660 and 3661 positioners are equipped with a 1/4 NPT vent connection in the cover.

Electrical Connections for 3661 Positioners

WARNING

For intrinsically safe installations, refer to the loop schematics shown in figures 27 and 29, factory drawings, or to
instructions provided by the barrier manufacturer for proper wiring and installation.

Select wiring and/or cable glands that are rated for the environment of use (such as hazardous area, ingress protection, and
temperature). Failure to use properly rated wiring and/or cable glands can result in personal injury or property damage
from fire or explosion.

Wiring connections must be in accordance with local, regional, and national codes for any given hazardous area approval.
Failure to follow the local, regional, and national codes could result in personal injury or property damage from fire or
explosion.

Refer to figures 17 and 18 when making electrical connections. Use the 1/2 NPT conduit connection for installation of
field wiring. Run the input wires through the conduit, and connect the positive wire from the control device to the
positioner + terminal and the negative wire from the control device to the positioner - terminal. Do not over tighten
the terminal screws. The maximum torque is 0.45 NSm (4 lbfSin.).

Figure 17. Equivalent Circuit

4 - 20 mA

21B2335‐D
A6012

+

5.6V

5.6V

−

5.6V

60 Ohms

60 Ohms

Figure 18. Typical Field‐Wiring Diagram

TERMINAL
BLOCK

CONTROL
DEVICE

NOTE:
1 FOR TROUBLESHOOTING OR MONITORING OPERATION,
AN INDICATING DEVICE CAN BE A VOLTMETER ACROSS
A 250 OHM RESISTOR OR A CURRENT METER.

A3875

+

-

FIELD WIRING

-+

1

EARTH
GROUND

POSITIONER
HOUSING

+

-

22

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Calibration

The following calibration procedures are for the adjustment of the pneumatic positioner. For the 3661 positioner,
there are no adjustments within the converter portion of the positioner. All adjustments are accomplished within the
pneumatic portion of the positioner.

WARNING

During calibration the valve may move. To avoid personal injury and property damage caused by the release of pressure or
process fluid, provide some temporary means of control for the process.

Refer to figure 24 (3660) or figure 25 (3661) for key number locations unless otherwise indicated. Adjustment
locations are shown in figure 19.

1. If mounting a new positioner on an actuator or if the positioner action has not been changed, do not perform
steps 2 through 7.

2. If the positioner action has been changed or if the positioner has had maintenance performed on it, complete
steps 3 through 17.

3. If the cover (key 21) has not been removed, unscrew the two machine screws (key 24), and remove the cover.

4. Release all pressure from the positioner. Disconnect the positioner output tubing to the actuator. If the positioner is
equipped with an output gauge, plug the positioner output connection. If the positioner is not equipped with an
output gauge, provide a gauge to monitor positioner output and connect it to the positioner output connection.

5. Set the supply pressure to the required setting. Set the gain (proportional band) adjustment screw at a nominal
value by turning it clockwise until it stops, and then turning it counterclockwise 1 turn.

Note

Adjusting the gain (PB) adjustment changes the nozzle flapper relationship. This nozzle flapper change affects the
actuator/positioner response time.

Note

To improve holding of the calibration tool as used in step 6, the actuator may be used to create the load (manual pressure) by
winding up the positioner range spring. The direction of windup, looking at the spring from outside the housing, must be
clockwise. This windup will create a torsional force over the input diaphragm through the lever assembly. The spring is
automatically wound up in two of the positioner/actuator mounting positions when the loading pressure is removed. These are
left‐hand mounting on a spring‐to‐close actuator and right‐hand mounting on a spring‐to‐open actuator (refer to figure 2). In the
other two mounting positions, the actuator must be pressurized to 100 percent input to create the spring holding force.

6. Remove the calibration tool (key 6) from the cover. Place the calibration tool between the lever assembly (key 17)
and the input diaphragm assembly (key 28). When making the following adjustment, apply manual pressure to the
lever assembly over the input diaphragm assembly to hold the calibration tool in place. Loosen the lock nut
(key 57), and turn the adjusting screw (key 18) until the output is 50% ± 10% of supply pressure. For example, if
supply pressure is 2.4 bar, set the output to 1.2 bar ± 0.24 bar.

7. Lock the adjusting screw (key 18) with the lock nut (key 57). After the adjustment is complete, remove the
calibration tool and replace it in the positioner cover.

23

3660 and 3661 Positioners

January 2013

Figure 19. Adjustment Locations (Equivalents of Pressures Shown in This Drawing are:
6 bar = 86 psig, 4 bar = 58 psig, and 1.4 bar = 20 psig)

REFER TO INSTRUCTION MANUAL FOR

POSITIONER ADJUSTMENT PROCEDURES

CALIBRATION

TOOL

CALIBRATION

WERKZEUG

OUTIL DE REGLAGE

Instruction Manual

D101402X012

R=REVERSE
UMGEKEHRT
INVERSE

28B0006‐B

ZERO
NULL PUNKT

D=DIRECT
NORMAL

DAMPING=H
D'A'MPFUNG
AMORTISSEMENT

INCREASE
TRAVEL

SUPPLY
ALIM.
ZUL.

GAIN
VERST'A'RKUNG

TRAVEL
HUB
COURSE

TURNS
UMDREHUNGEN
TOUR

8. Release all pressure from the positioner. Remove the plug or the gauge that was installed in step 4, and reconnect
the output tubing to the actuator.

9. Turn on supply pressure. Set the input signal to the minimum value.

10. Remove the cover (key 19T) from the feedback lever assembly (key 19).

11. Set the travel (span) adjustment to the desired actuator travel by loosening the hex nut (key 19D) and sliding the
pilot shaft (key 19A) to the desired setting on the feedback lever assembly (key 19). The travel settings are marked
in millimeters on the feedback lever assembly.

12. Set the gain (PB) adjustment and/or the output volume damping adjustment to a setting that provides the best
actuator/positioner response. Observe the gain dependency on the air supply pressure as shown in the graph of
figure 19. The gain adjustment restrictor for air delivery should be fully open for large size actuators and adjusted to

2

a mid‐value for smaller size actuators with 225 cm

(35 square inches) or less diaphragm area. Start by setting the
gain adjustment at approximately one turn open, and, if the output volume damping adjustment is used, turn it
clockwise to decrease the air delivery.

13. Adjust the valve stem position by rotating the zero adjustment screw (key 19S).

14. Set the input signal to the maximum value.

24

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

15. Readjust the travel (span) adjustment to achieve correct actuator travel.

Note

When a travel (span) adjustment is made, there will be a zero shift.

16. Repeat steps 11 through 15 as necessary to achieve correct actuator travel.

17. Install the cover (key 19T) on the feedback lever assembly (key 19) with cover screw (key 19U).

18. Install the positioner cover (key 21) and secure with the machine screws (key 24). Make sure the Fisher logo reads
correctly and the vent is pointing downward.

Split‐Range Operation

3660 and 3661 positioners can be used for split‐range operation with the instrument input signal from a single
controller or another instrument split between two or three control valves. Tables 7 and 8 show some typical split
ranges for the positioners. To change from a full range to a split range, change the range spring (key 30, figure 24 or

25) to the appropriate spring shown in the tables. Complete the Changing Range Spring portion of the Maintenance
section. Refer to tables 7 and 8 for valve stem travel available with split range operation.

Table 7. Range Spring Selection for Fisher Actuators

TYPE 3660 3660 3661

0.2 to 1.0 bar

Split

One Way 1:1 0.2 to 1.0 3 to 15 0.4 to 2.0 6 to 30 4 to 20 19 to 50 0.75 to 2.0 11B3880X012

Two Way 2:1

Three Way 3:1

(3 to 15 psig)

Input Signal

Bar Psig Bar Psig mm Inches

0.2 to 0.6

0.6 to 1.0

0.2 to 0.5

0.5 to 0.8

0.8 to 1.0

3 t0 9

9 to 15

3 to 7

7 to 11

11 to 15

0.4 to 2.0 bar
(6 to 30 psig)

Input Signal

0.4 to 1.2

1.2 to 2.0

0.4 to 1.0

1.0 to 1.5

1.5 to 2.0

6 to 18

18 to 30

6 to 14
14 to 22
22 to 30

4 to 30 mA DC

Input Signal

4 to 12

12 to 20

4 to 9.33

9.33 to 14.66

14.66 to 20

VALVE STEM TRAVEL

WHEN USING

3660 AND 3661

19 to 50 0.75 to 2.0 11B3881X012

15 to 33.3 0.591 to 1.311 11B3881X012

RANGE SPRING
PART NUMBER

(KEY 30)

25

3660 and 3661 Positioners

Instruction Manual

January 2013

Table 8. Range Spring Selection for Baumann Actuators

TYPE 3660 3661 VALVE STEM TRAVEL

0.2 to 1.0 bar
(3 to 15 Psig)

Input Signal

Split

One Way

1:1

Two Way

2:1

Three Way

3:1

Four Way

4:1

1. Pilot shaft setting is the A dimension in figure 20.

Range

Bar

(Psig)

0.2 to 1.0
(3 to 15)

0.2 to 0.6

(3 to 9)

0.6 to 1.0
(9 to 15)

0.2 to 0.5

(3 to 7)

0.5 to 0.8
(7 to 11)

0.8 to 1.0

(11 to 15)

0.2 to 0.4

(3 to 6)

0.4 to 0.6

(6 to 9)

0.6 to 0.8
(9 to 12)

0.8 to 1.0

(12 to 15)

Span

Bar

(Psi)

0.8

(12)

0.4
(6)

0.3
(4)

0.2
(3)

0.4 to 2.0 bar
(6 to 30 Psig)

Input Signal

Range

Bar

(Psig)

0.4 to 2.0
(6 to 30)

0.4 to 1.2
(6 to 18)

1.2 to 2.0

(18 to 30)

0.4 to 0.97
(6 to 14)

0.97 to 1.5

(14 to 22)

1.5 to 2.0

(22 to 30)

0.4 to 0.8
(6 to 12)

0.8 to 1.2

(12 to 18)

1.2 to 1.6

(18 to 24)

1.6 to 2.0

(24 to 30)

Span

Bar

(Psi)

1.6

(24)

0.8

(12)

0.55
(8)

0.4
(6)

4 to 20 mA DC

Input Signal

Range

mA

4 to 20 16 17B0662X012 89 (3.50) 17B0662X012 129 (5.09)

4 to 12

12 to 20

4 to 9.33

9.33 to 14.66

14.66 to 20

4 to 8

8 to 12
12 to 16
16 to 20

Span

mA

8 11B3880X012 92 (3.63) 11B3881X012 92 (3.63)

5.33 11B3881X012 70 (2.75) 11B3881X012 137 (5.38)

4 11B3881X012 95 (3.75) - - - - - -

12.7 to 19 mm

(1/2 to 3/4 inch)

Range Spring
Part Number

(key 30)

Approximate

Pilot Shaft

(1)

Setting

mm (Inch)

Range Spring
Part Number

19.1 to 50 mm
(3/4 to 2 inch)

(key 30)

D101402X012

Approximate

Pilot Shaft

(1)

Setting

mm (Inch)

Figure 20. Pilot Shaft Setting

A

PILOT SHAFT
(KEY 19A)

38B0195‐B

FEEDBACK LEVER
ASSEMBLY (KEY 19)

FEEDBACK SHAFT
LOCATION

3660 Bypass Operation

3660 positioners may be supplied with a bypass assembly.

CAUTION

Do not use bypass operation when the positioner is reverse acting or is in split‐range operation. In these cases, bypassing
the positioner sends the input signal directly to the actuator. Such a change will affect the desired operation and possibly

26

Instruction Manual

D101402X012

upset the system. Use bypass operation only when the instrument signal range is the same as the positioner output range
required for normal actuator operation.

3660 and 3661 Positioners

January 2013

Labels on the bypass body assembly (key 41, figure 23), and a pointer on the bypass lever (key 42 in figure 23) indicate
if the input signal from the instrument goes to the positioner or directly to the control valve actuator.

With the pointer of the bypass lever over the word POSITIONER, the instrument pressure goes to the positioner and
the output pressure of the positioner goes to the actuator.

With the pointer of the bypass lever over the word BYPASS, the instrument pressure goes directly to the actuator.

Note

A difference between the input signal pressure and the positioner output pressure could cause a transient bump in the controlled
system when the bypass lever is moved to BYPASS.

With a reverse‐acting or split‐range positioner, the bypass lever may be secured in the POSITIONER position so that
bypass cannot be used. To lock the bypass lever in the POSITIONER position, shut off the instrument and supply
pressure to the positioner. Then, move the bypass lever (key 42 in figure 23) so the pointer is over the word
POSITIONER. Align the hole in the pointer with the hole in the body assembly and thread the plastic wire tie (key 79 in
figure 23) through both holes to secure the bypass lever.

Principle of Operation

Refer to figure 21 for the operational schematic.

The instrument pressure acts on the input module, which controls the flapper‐nozzle system of the relay. Supply
pressure is applied to the relay, and the output pressure of the relay is supplied to the control valve actuator.

For a direct‐acting positioner, increases in instrument pressure cause the input module to pivot the beam. The beam
pivots the flapper and restricts the nozzle. The nozzle pressure increases and causes the relay assembly to increase
output pressure to the actuator. With a direct‐acting actuator, this increased pressure moves the actuator stem
downward. Stem movement is fed back to the beam by means of a feedback lever and range spring, which causes the
flapper to pivot slightly away from the nozzle to prevent any further increases in relay output pressure. The positioner
is once again in equilibrium but at a higher instrument pressure, a slightly different flapper position, and a new
actuator stem position.

A decrease in instrument pressure decreases nozzle pressure, which allows the relay to bleed off actuator loading
pressure.

Operation of a reverse‐acting positioner is similar except that the position of the flapper is reversed from that shown in
figure 21. The reversed position uses the alternate flapper pivot point so that increases in instrument pressure rotate
the flapper away from the nozzle to reduce nozzle pressure.

With a 3661 electro‐pneumatic positioner, the electro‐pneumatic (I/P) converter provides a 0.2 to 1.0 bar (3 to 15
psig) output pressure proportional to the 4-20 milliampere input signal. The 0.2 to 1.0 bar (3 to 15 psig) output
pressure becomes the input signal pressure to the input module.

27

3660 and 3661 Positioners

January 2013

Figure 21. Operational Schematic

FEEDBACK
PLATE

PILOT
SHAFT

FEEDBACK
LEVER

OUTPUT

RANGE
SPRING

PIVOT

INPUT MODULE

BEAM

RELAY

BEAM

Instruction Manual

D101402X012

FLAPPER

DIRECT
ACTING
PIVOT

GAIN ADJA

A

SUPPLY

RANGE
SPRING

SECTION A‐A

A

NOZZLE

RELAY

REVERSE
ACTING PIVOT

GAIN ADJ

A

SUPPLY

PIVOT

I/P CONVERTER

INPUT SIGNAL

31B3960‐C
B2152‐4

3660 POSITIONER

INPUT MODULE

3661 POSITIONER

Maintenance

Positioner parts are subject to normal wear and must be inspected and replaced as necessary. The frequency of
inspection and replacement depends upon the severity of service conditions. The following procedure describes
disassembly and reassembly of the positioner. When inspection or repairs are required, disassemble only those parts
necessary to accomplish the job. When reassembly is complete, make adjustments as described in the Calibration
section.

WARNING

Avoid personal injury or property damage from sudden release of process fluid. Before performing any Maintenance
procedures:

D Always wear protective clothing, gloves, and eyewear to avoid personal injury.

D Do not remove the actuator from the valve while the valve is still pressurized.

D Disconnect any operating lines providing air pressure, electric power, or a control signal to the actuator. Be sure the

actuator cannot suddenly open or close the valve.

D Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure

on both sides of the valve.

28

Instruction Manual

D101402X012

D Vent the power actuator loading pressure and relieve any actuator spring precompression.
D Use lock‐out procedures to be sure that the above measures stay in effect while you work on the equipment.
D For 3661 positioners in intrinsically safe areas, current monitoring during operation must be with an approved meter

for hazardous areas in order to avoid personal injury or property damage caused by an explosion or fire.

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

media.

3660 and 3661 Positioners

January 2013

Changing the Positioner Action

This section explains changing the positioner action from direct to reverse or reverse to direct. With direct action, the
positioner output pressure increases as the instrument input signal to the positioner increases. With reverse action,
the positioner output pressure decreases as the input signal to the positioner increases. To change the action of a
positioner that is already mounted on an actuator, remove the positioner from the actuator. Refer to the Removing
the Positioner from Actuator section. Refer to figure 24 or 25 for key number locations.

1. Unscrew the two captive cover screws and remove the cover (key 21). Carefully lift the flapper spring at the location
shown by key 10.

2. Slide out the flapper (key 9) and rotate it so that the desired letter (D or R for direct and reverse) is nearest the
adjusting screw (key 18). When inserting the flapper, be sure the end of the flapper engages the groove in the end
of the screw and that the flapper spring (key 10) sets into the V‐notches of the flapper.

3. Mount the positioner to the opposite actuator leg as explained in the Positioner Mounting section and shown in
figure 2.

4. Refer to the Calibration section of this manual for the calibration procedure.

Changing the Range Spring

Refer to figure 24 or 25 for key number locations.

1. Unscrew the two captive cover screws and remove the cover (key 21). Loosen the retaining screw (key 19P) and pull
the feedback lever assembly (key 19) out slightly to release the range spring (key 30) tension.

2. Remove and replace the range spring (key 30).

3. Push the feedback lever assembly (key 19) back into position and retighten the retaining screw (key 19P).

4. Refer to the Calibration section for the calibration procedure.

Changing the Input Signal Range on 3660 Positioners

To change the input signal range from 0.2 to 1.0 bar (3 to 15 psig) to 0.4 to 2.0 bar (6 to 30 psig) or vice versa, change
the input diaphragm assembly (key 28, figure 24) by performing the Changing the Input Module Diaphragm Assembly
procedure in this Maintenance section.

Removing the Positioner from the Actuator

Center‐Bolt Mounting on 1250, 1250R, 3024S, and Baumann Actuators

Refer to figure 24 or 25 for key number locations unless otherwise indicated.

WARNING

To avoid personal injury caused by electrical shock, disconnect electrical power to 3661 positioners.

29

3660 and 3661 Positioners

January 2013

1. Release all pressure from the positioner. Disconnect the supply, instrument, and output tubing. For 3661
positioners, disconnect the input wires and conduit.

2. Unscrew the two captive cover screws and remove the cover (keys 24 and 21). Loosen the retaining screw
(key 19P).

3. Pull the feedback lever assembly (key 19) out slightly to release the range spring tension, and remove the range
spring (key 30).

4. Loosen and remove the hex head screw and sealing washer (keys 72 and 71 in figure 3), and remove the positioner.

5. To mount the positioner on the actuator, refer to the Positioner Mounting section of this manual.

Instruction Manual

D101402X012

Clamp Mounting on 1250, 1250R, and 3024S Actuators

WARNING

To avoid personal injury caused by electrical shock, disconnect electrical power to 3661 positioners.

1. Release all pressure from the positioner. Disconnect the supply, instrument, and output tubing. For 3661
positioners, disconnect the input wires and conduit.

2. Unscrew and remove the hex nut and washer (keys 66 and 67 in figure 3), and remove the positioner.

3. To mount the positioner on the actuator, refer to the Positioner Mounting section.

Mounting Bracket/U‐Bolt Mounting on 657, and 667 Actuators

Refer to figure 24 or 25 for key number locations unless otherwise indicated.

1. Release all pressure from the positioner. Disconnect the supply, instrument, and output tubing. For 3661
positioners, disconnect the input wires and conduit.

2. Unscrew the two captive cover screws and remove the cover (keys 24 and 21). Loosen the retaining screw
(key 19P).

3. Pull the feedback lever assembly (key 19) out slightly to release the range spring tension, and remove the range
spring (key 30).

4. Loosen and remove the hex nut and washer (keys 90 and 89, figure 7), and remove the positioner.

5. To mount the positioner on the actuator, refer to the Positioner Mounting section.

Changing the Input Module Diaphragm Assembly

Refer to figure 24 or 25 for key number locations.

1. Unscrew the two captive cover screws, and remove the cover (key 21). Loosen the retaining screw (key 19P) and
pull the feedback lever assembly (key 19) out slightly to release the range spring (key 30) tension.

2. Remove the cheese head screw (key 7) from the beam and diaphragm assembly (key 28).

3. There are four cheese head screws (key 7) holding the diaphragm assembly (key 28) to the housing. Remove the
two cheese head screws (key 7) nearest the feedback lever assembly (key 19) and loosen the two remaining cheese
head screws (key 7). Slide the diaphragm assembly (key 28) out from between the lever assembly (key 17) and the
housing.

4. Install the new diaphragm assembly (key 28), and secure with the four cheese head screws (key 7).

5. Depress the feedback lever assembly (key 19) inward until it stops on the housing, and tighten with the retaining
screw (key 19P).

30

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

6. With the input pressure set at either 1.4 or 2.4 bar (20 or 35 psig), check for leaks between the diaphragm assembly
and the housing.

7. Refer to the Calibration section for the calibration procedure.

Disassembling and Assembling Relay Components

Before disassembling the relay components, remove the positioner from the actuator. Refer to the Removing the
Positioner from the Actuator section. Refer to figure 24 or 25 for key number locations.

1. To disassemble the relay valve assembly (key 2) or restrictor assembly (key 4), unscrew these parts from the back of
the positioner and replace with new parts.

The relay valve assembly (key 2) and the restrictor assembly (key 4) are marked with the letters V and P, respectively
on the removal screws. For correct location purposes, these same letters appear on the back of the positioner case.

2. Unscrew the two captive cover screws, and remove the cover. Loosen the retaining screw (key 19P) and pull the
feedback lever assembly (key 19) out slightly to release the range spring (key 30) tension. Remove the range spring
(key 30).

3. Remove the cheese head screw (key 7) from the lever assembly (key 17) and the diaphragm assembly (key 28).

4. Remove the two cheese head screws (key 7) that hold the lever assembly (key 17) to the housing and lift off the
lever.

5. Remove the four cheese head screws (key 11) and four washers (key 98). Lift off the flapper (key 9), flapper spring
stop (key 99), flapper spring (key 10) and cover plate assembly (key 8). Lift out the output diaphragm assembly
(key 29) and spring (key 3).

6. Reassemble the relay parts in the following order, spring (key 3), output diaphragm assembly (key 29), cover plate
assembly (key 8), flapper spring (key 10), and flapper spring stop (key 99). Install the four washers (key 98) and four
cheese head screws (key 11), and then tighten the screws. When tightening the two screws that secure the flapper
spring (key 10), position the spring so the spring tab is aligned over the center of the nozzle and the flapper is
parallel as shown in figure 22.

Figure 22. Flapper and Lever Alignment

INPUT
DIAPHRAGM
ASSEMBLY

A4042‐1

LEVER TO INPUT
MODULE MOUNTING
SCREW

LEVER MOUNTING
SCREWS

SPRING
TAB

FLAPPER ALIGNED
PARALLEL

ADJUSTING
SCREW / FLAPPER
ALIGNMENT

SPRING TAB
ALIGNED OVER
CENTER OF
NOZZLE

7. Reassemble the lever assembly (key 17) with the two cheese head screws (key 7). Do not tighten the screws until
the adjusting screw (key 18) to flapper (key 9) and tapped hole in the diaphragm assembly (key 28) are aligned
(refer to figure 22). Then, tighten the lever assembly and install the screw in the diaphragm assembly.

31

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

8. Carefully lift the flapper spring at the location shown by key 10. Install the flapper (key 9) so that the desired letter
(D or R for direct and reverse) is nearest the adjusting screw (key 18). When inserting the flapper, be sure the end of
the flapper engages the grove in the end of the screw, and that the flapper spring (key 10) sets into the V‐notches of
the flapper.

9. With the flapper (key 9) in place, visually ensure that it is aligned parallel to the cover plate assembly (key 8) as
shown in figure 22. Realign if necessary by repositioning the flapper spring (key 10). The flapper alignment affects
the performance of the positioner. Be careful not to damage the lapped surfaces on the cover plate and nozzle.

10. Reinstall the range spring (key 30). Push the feedback lever assembly (key 19) back into position and retighten the
retaining screw (key 19P).

11. With the output at supply pressure, check the output diaphragm assembly joints for leaks.

12. Refer to the Calibration section for the calibration procedure.

Disassembling and Assembling the Bypass Valve

During the following bypass valve disassembly and assembly procedures, refer to figure 23, unless otherwise
indicated.

Figure 23. Fisher 3660 Bypass Valve

11B3925‐B

1. Remove all pressure from the positioner. Disconnect the supply, instrument and output tubing.

2. Remove the two cheese head screws (key 47). Lift the bypass valve from the positioner being careful not to loose
the three O‐rings (key 49).

3. Remove the plastic wire tie (key 79) and retaining ring (key 46).

4. Using a gentle pulling and turning motion, slide the bypass lever assembly (key 42) from the bypass body (key 41).

5. Inspect the O‐rings (keys 43, 44, 45 and 49) for nicks and wear, and replace as necessary. When installing new
O‐rings (keys 43, 44 and 45) on the shaft of the bypass lever assembly, lubricate them sparingly using lubricant
(key 48).

6. Install the bypass lever assembly (key 42) into the body assembly (key 41) using a gentle turning and pushing
motion to avoid nicking an O‐ring.

7. Install the retaining ring (key 46).

32

Instruction Manual

D101402X012

8. Install the three O‐rings (key 49) into the body assembly (key 41) and then carefully attach the body assembly to the
positioner using the two cheese head screws (key 47).

9. Turn the bypass lever (key 42) to the appropriate POSITIONER or BYPASS position, and secure with the plastic wire
tie (key 79).

10. Reconnect the supply, instrument and output tubing, and turn on pressure to the positioner.

3660 and 3661 Positioners

January 2013

Replacing the 3661 Converter Module

Refer to figure 25 for key number locations. After replacing the converter module, re‐calibrate the positioner.

1. Remove the cover and disconnect the input signal wires from the terminal strip.

2. Loosen the two captive screws securing the converter to the positioner housing, and lift out the converter module
(key 100).

3. When replacing the converter module, the restrictor assembly (key 35) also should be replaced. Before the
restrictor assembly can be removed, remove the positioner from the actuator. Refer to the Removing the Positioner
from the Actuator section.

4. Remove and replace the restrictor assembly (key 35). This assembly is marked with the letters EP on the removal
screw. For location purposes, the same letters appear on the back of the positioner case.

5. To mount the positioner on the actuator, refer to the Positioner Mounting section.

6. Install a new converter, and secure to the housing with the two captive screws. Reconnect the input signal wires.

7. Refer to the Calibration section for the calibration procedure.

Parts Ordering

When corresponding with your Emerson Process Management sales office about this equipment, always mention the
positioner type number. When ordering replacement parts, refer to the part number of each required part as found in
the following parts list.

WARNING

Use only genuine Fisher replacement parts. Components that are not supplied by Emerson Process Management should
not, under any circumstances, be used in any Fisher instrument. Use of components not supplied by Emerson Process
Management may void your warranty, might adversely affect the performance of the instrument, and could result in
personal injury or property damage.

33

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Parts Kits

Repair Kits

Description Part Number

3660 w/0.2 to 1 bar
 (3 to 15 psig) input R3660X00012

3660 w/0.4 to 2 bar
 (6 to 30 psig) input R3660X00022
 These kits contain keys 9, 26, 27, 28, 29, 43, 44, 45,
 49, 95, and 97. Keys 43, 44, 45 and 49 are used for the
 3660 with bypass only. An additional O‐ring is included
 in kit R3660X00012, but is not used for the 3660.

3661 R3660X00012
 This kit contains keys 9, 26, 27, 28, 29, 43, 44, 45, 49,
 95, and 97. Keys 43, 44, 45, and 49 are included in kit
 R3660X00012, but they are not used for the 3661.
 An additional O‐ring is also included in the kit for the I/P
 converter outlet.

Description Part Number

3024S

kit contains key numbers 64, 65, 66,
  67, 68, 69, and 70 21B3931X0C2

GX

kit contains key numbers 68, 69,
  71, and 72 GE04613X0A2

Parts List

Note

Part numbers are shown for recommended spares only. For part
numbers not shown, contact your Emerson Process Management sales
office.

Positioner Common Parts

Key Description Part Number

Mounting Kits

1250 and 1250R

Sizes 30 and 34
  Clamp mounting
   kit contains key numbers 64,
    65, 66, 67, 68, 69, and 70 21B3931X0A2
  Center‐bolt mounting
   kit contains key numbers 68,
    69, 70, 71, and 72 21B3932X0A2

1250 and 1250R

Size 45
  Clamp mounting
   kit contains key numbers 64, 65, 66, 67,
    68, 69, 70, and 101 through 104 21B3931X0B2
  Center‐bolt mounting
   kit contains key numbers 68, 69, 70, 71,
    72, and 101 through 104 21B3932X0B2

657 and 667

Sizes 30, 34, and 40
  kit contains key numbers 69, 70, 82, 83, 84,
   85, 86, 87, 88, 89, 90, 91, 92, and 93 31B6741X0A2
 Sizes 45 and 46
  kit contains key numbers 70, 82, 83, 84, 85,
   86, 87, 88, 89, 90, 91, 92, and 93 31B6741X0B2
 Sizes 50 and 60
  kit contains key numbers 70, 82, 83, 84, 85,
   86, 87, 88, 89, 90, 91, 92, and 93 31B6741X0C2

  1 Housing assembly, A03600

 For 3660

For 3661
  2* Valve assembly, A96061 11B3889X012
  3 Spring, 316 stainless steel
  4* Restrictor assembly, aluminum (includes

 filtration screen) 11B3887X012

5 Damping screw, stainless steel
  6 Calibration tool, aluminum
  7 Cheese head screw stainless steel

 (7 req'd for 3660;

13 req'd for 3661)
  8 Cover plate assembly, aluminum
  9* Flapper, A95052 11B3903X012
 10 Flapper spring, stainless steel
 11 Cheese head screw, stainless steel (4 req'd)
 12 Restrictor screw, stainless steel

17 Lever assembly, aluminum
 18 Adjusting screw, stainless steel
 19 Feedback lever assembly, stainless steel

 Standard

 For Baumann actuators

Note

Parts 19A through 19U are shown in figure 26.

3024C

kit contains key numbers 68, 69, 70,
  71, and 72 21B3932X0C2

34

19A Pilot Shaft
19B Locknut
19C Washer

*Recommended spare parts

Instruction Manual

D101402X012

Figure 24. Fisher 3660 Positioner Assembly

3660 and 3661 Positioners

January 2013

D

D

VIEW D‐D

51B3944‐F

Key Description Part Number

19D Nut
19E Lever Sub‐assembly

 Standard

For Baumann actuators
19F Zero Shaft
19G* Slide Bearing (2 req'd) 11B3916X012
19H Housing Bushing
19J Retaining Ring
19K* Disc 11B3918X012
19L* O‐ring 11B8369X012
19M* O‐ring 11B8368X012
19N Spring
19P Retaining Screw
19Q Retaining Ring
19R Roll Pin
19S Zero Adjust Screw
19T Cover
19U Cover Screw
 21 Cover assembly, aluminum
 24 Machine screw, stainless steel (2 req'd)
 26* O‐ring, EPDM (2 req'd for 3660;

 3 req'd for 3661) 11B3935X012

WITHOUT GAUGES

SECTION C‐C

Key Description Part Number

27 O‐ring, EPDM (2 req'd)
 28* Diaphragm assembly, aluminum

 3660 and 3661

0.2 to 1.0 bar (3 to 15 psig) 11B3871X012
 3660 only, 0.4 to 2.0 bar (6 to 30 psig) 11B3875X012

 29* Output diaphragm assembly, aluminum 11B3897X012

 30 Range spring, N09902 nickel alloy

Standard 11B3880X012
 Split range 11B3881X012
 For Baumann actuators 17B0662X012

 32 Nameplate, A91100

33 Ground terminal for 3661 (2 req'd)
 34 Cable gland for 3661, plastic
 35 I/P restrictor ass'y for 3661, aluminum

36 Pipe plug for 3661, stainless steel
 37 Machine screw, stainless steel

*Recommended spare parts

35

3660 and 3661 Positioners

January 2013

Figure 24. Fisher 3660 Positioner Assembly (continued)

A

A

B

Instruction Manual

D101402X012

C

B

VIEW A‐A

51B3944‐F

Key Description Part Number

 38* Output gauge (optional)

 Dual scale

  0 to 2 Kg/cm

  0 to 11 Kg/cm

 Triple scale

  0 to 2 bar/0 to 0.2 MPa/0 to 30 psig 11B4036X012

  0 to 11 bar/0 to 1.1 MPa/0 to 160 psig 11B4036X032

 39* Instrument gauge (optional for 3660 Only)

 Dual Scale

  0 to 2 Kg/cm

  0 to 4 Kg/cm

 Triple scale

  0 to 2 bar/0 to 0.2 MPa/0 to 30 psig 11B4036X012

  0 to 4 bar/0 to 0.4 MPa/0 to 60 psig 11B4036X022

 40 Anti‐seize sealant

 (not furnished with positioner)

2/

0 to 30 psig 11B4036X042

2/

0 to 160 psig 11B4036X062

2/

0 to 30 psig 11B4036X042

2/

0 to 60 psig 11B4036X052

WITHOUT COVER

C

SECTION B‐B

Key Description Part Number

Note

Keys 41 through 49 and key 79 apply to 3660 with bypass valve only.
Refer to figure 23.

41 Bypass body assembly, aluminum
 42 Bypass lever assembly, plastic
 43* O‐ring, EPDM 1J4888X0022
 44* O‐ring, EPDM 11A8741X032
 45* O‐ring, (2 req'd) 11B8420X012
 46 Retaining ring, stainless steel
 47 Cheese head screw, (2 req'd)
 48 Lubricant, silicone sealant

(not furnished with positioner)
 49* O‐ring, EPDM (3 req'd) 10A3716X032
 50 Lubricant, silicone sealant

 (not furnished with positioner)

36

*Recommended spare parts

Instruction Manual

D101402X012

Figure 25. Fisher 3661 Positioner Assembly

D

A

D

A

3660 and 3661 Positioners

January 2013

VIEW D‐D

VIEW A‐A

WITH M20 CABLE GLAND

51B3945‐J

SECTION C‐C

B

C

B

C

VIEW A‐A

WITHOUT COVER

37

3660 and 3661 Positioners

January 2013

Figure 25. Fisher 3661 Positioner Assembly (continued)

SECTION B‐B

Instruction Manual

D101402X012

51B3945

Key Description Part Number

 51 Adhesive, Loctite

(not furnished with positioner)
 54 Self‐tapping screw, stainless steel (2 req'd)
 55 Cover plate for 3661, A95052

56* Cover plate gasket for 3661, silicone 11B3869X012
 57 Hex nut, aluminum/chromate
 58 Pipe plug, stainless steel

 1 req'd for 3661 w/o output gauge option

 2 req'd for 3660 & 3661 w/o instrument

  and output gauge option

38

R

4210t PrismR Instant Adhesive,

Key Description Part Number

 79 Wire tie for 3660 with bypass valve only,

 plastic

 95* O‐ring, EPDM

 (2 req'd for 3660; 3 req'd for 3661) 11B8302X012

96 Plain washer, stainless steel
 97* Cover screw gasket, silicone (2 req'd) 11B8414X012

98 Washer, stainless steel (4 req'd)
 99 Flapper spring stop, stainless steel
100* I/P converter module for 3661 33B7075X022

*Recommended spare parts

Instruction Manual

D101402X012

3660 and 3661 Positioners

January 2013

Diagnostic Connections

FlowScanner Valve Diagnostic System Hookup
Includes pipe tees, pipe nipples, pipe bushings,
connector bodies, and body protectors.

Note

Part numbers are shown for recommended spares only. For part
numbers not shown, contact your Emerson Process Management sales
office.

Key Description

For 3660 Positioner

 For units with supply gauge

  SST fittings

  Brass fittings

 For units without supply gauge

  SST fittings

  Brass fittings

For 3661 Positioner

 For units with supply gauge

  SST fittings

  Brass fittings

 For units without supply gauge

  SST fittings

  Brass fittings

Key Description

 77 Cap screw, pl steel (2 req'd)

For 657, 667, 1250, 1250R, 3024S
  and GX

 78 Hex nut, zinc pl steel (2 req'd)

For 657, 667, 1250, 1250R, 3024S
  and GX

Note

The following mounting parts are included in Mounting Kits listed on
page 34.

1250 and 1250R Actuators

64 Bracket, clamp mounting only, A03600
 65 Stud, clamp mounting only, stainless steel

(2 req'd)
 66 Hex nut, clamp mounting only, steel (4 req'd)
 67 Washer, clamp mounting only, steel (2 req'd)

68 Feedback plate, stainless steel
 69 Hex head screw, stainless steel (2 req'd)
 70 Washer, stainless steel (2 req'd)

Mounting Parts

Common Mounting Parts

Note

Keys 73 through 78 apply to regulator mounting parts (casing mounted
only).

Key Description

 73 Bracket, pl steel

For 657, 667, 1250, 1250R, 3024S
  and GX

 74 Cap screw, 304 stainless steel (2 req'd)

 For 1250, 1250R, and 3024S

 75 Washer, pl steel (2 req'd)

 1250, 1250R, and 3024S

 76 Lockwasher, pl steel (2 req'd)

For 1250, 1250R, 3024S,
Lockwasher and Hex Nut (1 req'd)
 For GX

71 Washer, center bolt mounting only
 72 Hex head screw, center bolt mounting only,

 stainless steel

101 Lockwasher, stainless steel (2 req'd)

 For size 45, 20 to 30 mm travel only

102 Machine screw, stainless steel (2 req'd)

 For size 45, 20 to 30 mm travel only

103 Feedback adaptor, stainless steel

 For size 45, 20 to 30 mm travel only

104 Wedge nut, stainless steel (2 req'd)

 For size 45, 20 to 30 mm travel only

3024S Actuator

64 Mounting Bracket
65 Stud, stainless steel (2 req'd)

66 Hex nut, steel (4 req'd)
 67 Washer, steel (2 req'd)
 68 Feedback plate, stainless steel
 69 Hex head screw, stainless steel (2 req'd)
 70 Washer, stainless steel (2 req'd)

39

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Key Description

3024C Actuator

68 Feedback Plate
 69 Socket head screw (2 req'd)
 70 Washer, stainless steel (2 req'd)
 71 Washer, sealing
 72 Screw, Hex Head

657 and 667 Actuators

 69 Hex head screw, stainless steel (2 req'd)

Sizes 30, 34 and 40
 70 Washer, pl steel (2 req'd)
 82 Mounting Bracket, stainless steel

 83 Stud clamp, stainless steel

Key Description

 84 U‐bolt, stainless steel (2 req'd)

 Sizes 50 and 60

Sizes 30, 34, 40, 45 and 46
 85 Washer, stainless steel (4 req'd)
 86 Hex nut, stainless steel (4 req'd)
 87 Connector bracket, stainless steel
 88 Feedback arm, stainless steel
 89 Sealing washer
 90 Hex nut, stainless steel
 91 Machine screw, stainless steel (2 req'd)
 92 Washer, stainless steel (2 req'd)
 93 Hex nut, stainless steel (2 req'd)

GX Control Valve and Actuator System

68 Feedback Plate
 69 Socket head screw (2 req'd)
 71 Washer, sealing
 72 Screw, Hex Head

40

Instruction Manual

D101402X012

Figure 26. Feedback Lever Assembly

19R

19S

3660 and 3661 Positioners

January 2013

28B9418‐B

19P

19T

19J

19H

19S

19P

19J

19H

19Q

19F

19R

19K

19G

19L

19M

19N

19U

STANDARD

19K

19G

19L

19M

19D

19A

19B

19C

19A

19B

19E

19E

28B9423‐B

19T

19Q

19F

19N

19D

19U

FOR BAUMANN ACTUATORS

19C

41

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Loop Schematics/Nameplates for 3661 Positioner

This section includes loop schematics required for wiring of intrinsically safe installations, as well as typical approvals
nameplates. If you have any questions, contact your Emerson Process Management sales office.

Figure 27. CSA Loop Schematic for Fisher 3661 Positioner

HAZARDOUS LOCATION NON-HAZARDOUS LOCATION

INTRINSIC SAFETY

CLASS I, II, III, DIV 1, GROUPS A,B,C,D,E,F,G

NON-INCENDIVE

CLASS I, DIV 2, GROUPS A,B,C,D

CSA APPROVED BARRIERFISHER TYPE: 3661

Vmax = 30 VDC

Imax = 150 mA

Ci = 0 nF

Li = 0 mH

Pi = 1.25 W

NOTES:

1. BARRIERS MUST BE CSA CERTIFIED WITH ENTITY PARAMETERS
AND ARE TO BE INSTALLED IN ACCORDANCE WITH THE
MANUFACTURERS I.S. INSTALLATION INSTRUCTIONS.

2. EQUIPMENT SHALL BE INSTALLED IN ACCORDANCE WITH
THE CANADIAN ELECTRICAL CODE, PART I.

3. FOR ENTITY INSTALLATION (I.S. AND NI): Vmax > Voc, Imax > Isc,
Ci + Ccable < Ca, Li + Lcable < La.

GE28591‐A

Figure 28. Typical CSA/FM Approval Nameplate for Fisher 3661 Positioner

42

Instruction Manual

D101402X012

Figure 29. FM Loop Schematic for Fisher 3661 Positioner

HAZARDOUS LOCATION NON-HAZARDOUS LOCATION

INTRINSIC SAFETY

CLASS I, II, III, DIV 1, GROUPS A,B,C,D,E,F,G
CLASS I ZONE 0 AEx ia IIC

NON-INCENDIVE

CLASS I, DIV 2, GROUPS A,B,C,D

3660 and 3661 Positioners

January 2013

FISHER TYPE: 3661

Vmax = 30 VDC

Imax = 150 mA

Ci = 0 nF

Li = 0 mH

Pi = 1.25 W

WARNING

FOR INTRINSICALLY SAFE APPLICATIONS: THE APPARATUS ENCLOSURE CONTAINS
ALUMINUM AND IS CONSIDERED TO CONSTITUTE A POTENTIAL RISK OF IGNTION BY
IMPACT AND FRICTION. AVOID IMPACT AND FRICTION DURING INSTALLATION AND USE TO
PREVENT RISK OF IGNTION.

NOTES:

1. THE INSTALLATION MUST BE IN ACCORDANCE WITH THE NATIONAL ELECTRIC CODE (NEC),
NFPA 70, ARTICLE 504 AND ANSI/ISA RP12.6 OR ARTICLE 505.

2. CLASS 1, DIV 2 APPLICATIONS MUST BE INSTALLED AS SPECIFIED IN NEC ARTICLE 501-4(B).
EQUIPMENT AND FIELD WIRING IS NON-INCENDIVE WHEN CONNECTED TO APPROVED
BARRIERS WITH ENTITY PARAMETERS.

3. LOOPS MUST BE CONNECTED ACCORDING TO THE BARRIER MANUFACTURE'S INSTRUCTIONS.

4. MAXIMUM SAFE AREA VOLTAGE SHOULD NOT EXCEED 250 Vrms.

5. RESISTANCE BETWEEN BARRIER GROUND AND EARTH GROUND MUST BE LESS THAN ONE OHM.

6. NORMAL OPERATING CONDITIONS 30 VDC 20 mADC.

3. FOR ENTITY INSTALLATION (I.S. AND NI):

GE28590‐B

Vmax > Voc or Vt Ci + Ccable < Ca,
Imax > Isc or It Li + Lcable < La.
Pi > Po, or Pt

FM APPROVED BARRIER

Figure 30. Typical ATEX/IECEx Approval Nameplate for Fisher 3661 Positioner

43

3660 and 3661 Positioners

January 2013

Instruction Manual

D101402X012

Neither Emerson, Emerson Process Management, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance
of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.

Fisher, Baumann, and FlowScanner are marks owned by one of the companies in the Emerson Process Management business unit of Emerson Electric Co.
Emerson Process Management, Emerson, and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the property
of their respective owners.

The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not
to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are
governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such
products at any time without notice.

Emerson Process Management

Marshalltown, Iowa 50158 USA
Sorocaba, 18087 Brazil
Chatham, Kent ME4 4QZ UK
Dubai, United Arab Emirates
Singapore 128461 Singapore

www.Fisher.com

44

E1987, 2013 Fisher Controls International LLC. All Rights Reserved