Fisher 3660 User manual

www.Fisher.com
Fisherr3660 and 3661 Positioners
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 BaumanntActuators 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 for 3661 Positioners 42...........
Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
2
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
Phone: [phone] or [phone]
e‐mail: [email protected]
http://www.emersonprocess.com/education

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
3
Table 1. Specifications
Available Configuration
3660: Single‐acting pneumatic valve positioner
3661: Single‐acting electro‐pneumatic valve
positioner
Input Signal
3660
J0.2 to 1.0 bar (3 to 15 psig),
J0.4 to 2.0 bar (6 to 30 psig), or
Jsplit range (see tables 7 and 8)
3661:
J4 to 20 mA DC constant current with 30 VDC
maximum compliance voltage.
Jsplit 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:
JDirect (increasing input signal pressure increases
positioner output),
JReverse (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 61326‐1:2013
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
Positioner Adjustments
Span: JAdjustable up to 20 mm (0.75 inch) stem
travel, or JAdjustable 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 m3/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 m3/hour
(260 scfh)
Steady‐State Air Consumption(4,5)
3660: 0.17 normal m3/hour (6.0 scfh) at 1.4 bar
(20 psig) supply pressure. 0.22 normal m3/hour
(7.9 scfh) at 2.4 bar (35 psig) supply pressure
3661: 0.24 normal m3/hour (8.8 scfh) at 1.4 bar
(20 psig) supply pressure. 0.33 normal m3/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
0.16%(6) of travel
Operative Temperature Limits(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
- continued -

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
4
Table 1. Specifications (Continued)
Hazardous Area Classification for 3661
CSA & FM—Intrinsically Safe, Type n, Non‐incendive
ATEX & IECEx—Intrinsically Safe, Type n
(Gas Atmospheres Only)
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.
FM—NEMA 3, IP54
ATEX & IECEx—IP44
Mounting orientation requires vent location to be
below horizontal.
Other Classifications/Certifications for 3661
CUTR—Customs Union Technical Regulations (Russia,
Kazakhstan, Belarus, and Armenia)
INMETRO— National Institute of Metrology, Quality,
and Technology (Brazil)
KGS—Korea Gas Safety Corporation (South Korea)
Contact your Emerson Process Management sales
office for classification/certification specific
information
Mounting
The positioner can be mounted in one of four
different configurations. See figure 2 for mounting.
Pressure Connections
1/4 NPT internal
Conduit Connection for 3661
1/2 NPT (M20 or PG13 adaptors, optional)
Maximum Valve Stem Travel
Two ranges:
J50 mm (2 inch) to 20 mm (0.75 inch) minimum;
J20 mm (0.75 inch) adjustable to lesser travel with
standard input signal
Approximate Weight
3660: 1.2 kg (2.6 pounds)
3661: 1.4 kg (3.0 pounds)
Vent Connection
1/4 NPT internal
Options
3660: JInstrument and output pressure gauges,
JIntegrally 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.
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 m3/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).
5. Air consumption at a gain setting of 1/2 turn.
6. At supply pressure of 2.4 bar (35 psig).
Table 2. Fisher 3661 Positioner EMC Summary Results—Immunity
Port Phenomenon Basic Standard Test Level Performance
Criteria(1)
Enclosure
Electrostatic discharge (ESD) IEC 61000‐4‐2 4 kV contact
8 kV air A
Radiated EM field IEC 61000‐4‐3
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%
A
Rated power frequency magnetic field IEC 61000‐4‐8 60 A/m at 50 Hz A
I/O
signal/control
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
Specification limit = ±1% of span
1. A = No degradation during testing. B = Temporary degradation during testing, but is self‐recovering.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
5
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. Contact your Emerson Process Management sales
office for approval/certification information not listed here.
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
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Table 3. Hazardous Area Classifications for Fisher 3661 Positioner—CSA (Canada)
Certification Body Certification Obtained Entity Rating Temperature Code
CSA
Intrinsically Safe
Ex ia IIC T4/T5/T6 per drawing GE28591 (see figure 27)
Class I, II Division 1 GP A,B,C,D,E,F,G T4/T5/T6
per drawing GE28591 (see figure 27)
Vmax = 30 VDC
Imax = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH
T4 (Tamb ≤82°C)
T5 (Tamb ≤62°C)
T6 (Tamb ≤47°C)
Type n
Ex nA IIC T6 - - - T6 (Tamb ≤82°C)
Class I Division 2 GP A,B,C,D T6 - - - T6 (Tamb ≤82°C)
FM
Intrinsically Safe, Type n, and Non‐incendive
No special conditions for safe use.
Refer to table 4 for approval information.
Table 4. Hazardous Area Classifications for Fisher 3661 Positioner—FM (United States)
Certification Body Certification Obtained Entity Rating Temperature Code
FM
Intrinsically Safe
Class I Zone 0 AEx ia IIC T4/T5/T6
per drawing GE28590 (see figure 28)
Class I, II, III Division 1 GP A,B,C,D,E,F,G T4/T5/T6
per drawing GE28590 (see figure 28)
Vmax = 30 VDC
Imax = 150 mA
Pi = 1.25 W
Ci = 0 nF
Li = 0 mH
T4 (Tamb ≤82°C)
T5 (Tamb ≤62°C)
T6 (Tamb ≤47°C)
Type n
Class I Zone 2 AEx nA IIC T5 - - - T5 (Tamb ≤82°C)
Class I Division 2, GP A,B,C,D T5
Class II, III Division 2, GP F,G T5 - - - T5 (Tamb ≤82°C)
ATEX
Special Conditions for Safe Use
Intrinsically Safe
Thisequipment 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: U0≤30 Vdc; I0≤150 mA; P0≤1.25 W.
Ambient Temperature:
T6, at Tamb = 47_C
T5, at Tamb = 62_C
T4, at Tamb = 82_C
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
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Table 5. Hazardous Area Classifications for Fisher 3661 Positioner—ATEX
Certificate Certification Obtained Entity Rating Temperature Code
ATEX
II 1 G
Intrinsically Safe
Gas
Ex ia IIC T4/T5/T6 Ga
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)
II 3 G
Type n
Gas
Ex nA IIC T6 Gc
- - - T6 (Tamb ≤62°C)
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
Ui =30 V, li = 150 mA, Pi = 1.25 W, Ci = 0 nF, Li = 0 mH
Type n
WARNING
Disconnect power before opening.
-40_C Ta +82_C; T6 (Ta +82_C)
Refer to table 6 for additional approval information.
Table 6. Hazardous Area Classifications for Fisher 3661 Positioner—IECEx
Certificate Certification Obtained Entity Rating Temperature Code
IECEx
Intrinsically Safe
Gas
Ex ia IIC T4/T5/T6 Ga
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)
Type n
Gas
Ex nA IIC T6 Gc
- - - T6 (Tamb ≤82°C)

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
8
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
9
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
Up to 6.2 bar (90 psig)
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
ACTUATOR: AIR‐TO‐RETRACT
POSITIONER ACTION: DIRECT
(INCREASING INPUT SIGNAL INCREASES
OUTPUT PRESSURE TO ACTUATOR)
INPUT SIGNAL
AIR SUPPLY
OUTPUT
PILOT SHAFT
1
ACTUATOR: AIR‐TO‐RETRACT
POSITIONER ACTION: REVERSE
(INCREASING INPUT SIGNAL DECREASES
OUTPUT PRESSURE TO ACTUATOR)
INPUT SIGNAL
AIR SUPPLY
OUTPUT
FEEDBACK
PLATE
2
ACTUATOR: AIR‐TO‐EXTEND
POSITIONER ACTION: REVERSE
(INCREASING INPUT SIGNAL DECREASES
OUTPUT PRESSURE TO ACTUATOR)
INPUT SIGNAL
AIR SUPPLY
OUTPUT
1
ACTUATOR: AIR‐TO‐EXTEND
POSITIONER ACTION: DIRECT
(INCREASING INPUT SIGNAL INCREASES
OUTPUT PRESSURE TO ACTUATOR)
INPUT SIGNAL
AIR SUPPLY
OUTPUT
2
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

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
10
Figure 3. Positioner Mounting on Fisher 1250, 1250R, and 3024S Actuators
41B3946‐F
NIPPLE MOUNTED
FILTER REGULATOR
CLAMP MOUNT
SECTION A‐A
CENTER BOLT
MOUNT
SIZE 45 WITH TRAVEL BETWEEN
20 AND 30 mm (0.787 AND 1.18 INCHES)
AA
WEDGE NUT
(KEY 104)
FEEDBACK
PLATE
(KEY 68)
FEEDBACK
ADAPTOR
(KEY 103)
LOCKWASHER
(K3Y 101)
MACHINE
SCREW
(KEY 102)
FEEDBACK
LEVER
ASSEMBLY
FILTER
REGULATOR

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
11
Figure 4. Feedback Plate Orientation with Positioner Mounted on Fisher 1250, 1250R, and 3024S Actuators
FOR SIZE 30 AND 34 ACTUATORS WITH TRAVEL
BETWEEN 20 AND 30 mm (0.787 AND 1.18 INCHES)
POSITIONER
ACTUATOR LEG STEM CONNECTOR
FEEDBACK
PLATE
PILOT SHAFT FEEDBACK LEVER
ASSEMBLY
FOR SIZE 30,34 AND 45 ACTUATORS WITH
TRAVEL GREATER THAN 30mm (1.18 INCHES)
POSITIONER
ACTUATOR LEG STEM CONNECTOR
FEEDBACK
PLATE
PILOT SHAFT
FEEDBACK LEVER
ASSEMBLY
B2260‐1
FOR SIZE 45 ACTUATORS WITH TRAVEL BETWEEN
20 AND 30 mm (0.787 AND 1.18 INCHES)
STEM CONNECTOR
FEEDBACK
PLATE
ACTUATOR STEM
FEEDBACK
ADAPTOR
VALVE STEM
USE THESE HOLES
WHEN MOUNTING
THE FEEDBACK
ADAPTOR TO THE
FEEDBACK PLATE
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

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
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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
A4949‐1
THIN SECTION
ACTUATOR
STEM
VALVE
STEM
FEEDBACK LEVER
ARM ASSEMBLY
FEEDBACK
PLATE
PILOT SHAFT
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.
1
A7223
Figure 6. Feedback Plate Installation for Baumann
Actuators
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
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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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
14
Figure 7. Positioner Mounting on Fisher 657 and 667 Actuators
FILTER
REGULATOR
41B6744‐D
SECTION A‐A
TO POSITIONER
OUTPUT
667
NIPPLE MOUNTED
FILTER REGULATOR
AA
APPLY LUB

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
15
Figure 8. Feedback Arm Orientation with Positioner Mounted on Fisher 657 and 667 Actuators
B2256‐1
SIZES 30 THROUGH 40 ACTUATORS WITH
TRAVEL UP TO 30 mm (1.18 INCHES)
SIZES 30 THROUGH 40 ACTUATORS WITH
TRAVEL GREATER THAN 30 mm (1.18 INCHES)
SIZES 45 THROUGH 60 ACTUATORS WITH
TRAVEL GREATER THAN 30 mm (1.18 INCHES)
ACTUATOR STEM
PILOT SHAFT
PILOT SHAFT
PILOT SHAFT
PILOT SHAFT
POSITIONER
POSITIONER
POSITIONER
POSITIONER
STEM CONNECTOR
STEM
CONNECTOR
STEM CONNECTOR
STEM CONNECTOR ACTUATOR STEM
ACTUATOR STEM
ACTUATOR STEM
CONNECTOR
BRACKET
CONNECTOR
BRACKET
CONNECTOR
BRACKET
CONNECTOR
BRACKET
CONNECTOR
BRACKET
CONNECTOR
BRACKET
FEEDBACK LEVER
ASSEMBLY
FEEDBACK LEVER ASSEMBLY
FEEDBACK
LEVER ASSEMBLY
FEEDBACK LEVER
ASSEMBLY
FEEDBACK
ARM
FEEDBACK
ARM
FEEDBACK
ARM
FEEDBACK ARM
VALVE STEM
VALVE STEM
FEEDBACK
ARM
ACTUATOR LEG
ACTUATOR LEG ACTUATOR LEG
ACTUATOR LEG
VIEW A
VIEW B
A
A
B
B
SIZES 45 THROUGH 60 ACTUATORS WITH
TRAVEL UP TO 30 mm (1.18 INCHES)
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
16
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
17
Figure 9. Installing the Feedback Lever Assembly
(Key 19) on the Positioner
RETAINING
SCREW
(KEY 19P)
ANTI‐ROTATING SLOT
W7367
Figure 10. Positioning Feedback Spring
ZERO
ADJUSTMENT
COVER
FEEDBACK
SHAFT
SPRING PIN
FEEDBACK SPRING
FEEDBACK SPRING MUST
HOOK AROUND SPRING
PIN END OPPOSITE THE
ZERO ADJUSTMENT
SCREW
27B9999‐D
A7224
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
18
Figure 11. Range Spring Installation
LEVER
ASSEMBLY
FEEDBACK
SHAFT
W7366
Figure 12. Range Spring Alignment
A5211
STRAIGHT PORTION
OF SPRING RANGE SPRING
FEEDBACK
SHAFT
SLOT
SECTION A
BOSS
LEVER
ASSEMBLY
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

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
19
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.

Instruction Manual
D101402X012
3660 and 3661 Positioners
September 2015
20
Figure 15. Typical Mounting Dimensions and Connections
ACTUATOR CENTERLINE TO POSITIONER
Type Size Dimension X
mm Inch
657/667
30
34
40
45/46
50/60
92.2
95.3
104.9
108.0
128.5
3.63
3.75
4.13
4.25
5.06
1250
225
450
675
86.0
86.0
110.0
3.39
3.39
4.33
3024S
1.21
1.31
1.41
83.5
87.5
87.5
3.29
3.44
3.44
Baumann
16in2
32in2
54in2
70in2
53.8
71.4
71.4
71.4
2.12
2.81
2.81
2.81
GX
225
750
1200
81.0
81.0
81.0
3.19
3.19
3.19
31B3959‐C
C0686‐3
ACTUATOR POST CENTERLINE
34.32
(1.35)
49.2
(1.94)
191.2
(7.53)
93
(3.66)
49
(1.93)
34.32
(1.35)
ACTUATOR POST
CENTERLINE
142.2
(5.60)
49.2
(1.94) 93
(3.66)
ACTUATOR
CENTERLINE
ACTUATOR
CENTERLINE
DIM X
122.3
(4.81)
30
(1.18)
30
(1.18)
21.5
(0.85)
1/4 NPT
OUTPUT
CONNECTION
1/4 NPT
INSTRUMENT
CONNECTION
1/4 NPT
INSTRUMENT
CONNECTION
1/4 NPT
OUTPUT
CONNECTION
122.3
(4.81)
67.5
(2.66) DIM X
27.5
(1.08)
1/2 NPT
3661 I/P ONLY mm
(INCH)
67.5
(2.66)
0.5
(.02)
30
(1.18)
30
(1.18)
21.5
(0.85)
1/4 NPT
SUPPLY
CONNECTION
1/4 NPT
SUPPLY
CONNECTION