Emerson Fisher 656 - User Manual

www.Fisher.com
Fisher
™
656 Diaphragm Actuator
Contents
Introduction 1.................................
Scope of Manual 1.............................
Description 1.................................
Principle of Operation 2.........................
Specifications 2...............................
Maximum Pressure Limitations 3................
Installation 3..................................
Adjustment 3..................................
Maintenance 4.................................
Disassembly 4................................
Assembly 5...................................
Parts Ordering 7................................
Parts List 7....................................
Handwheel Assembly 7........................
Casing‐Mounted Adjustable Down
Travel Stop 11..............................
Figure 1. Fisher 656 Actuator
W0454
Introduction
Scope of Manual
This instruction manual includes installation, maintenance, and parts information for Fisher 656 diaphragm actuators.
Refer to separate manuals for instructions covering the valve, positioner, and accessories.
Description
Fisher 656 actuators are long stroke, spring opposed, direct‐acting diaphragm actuators. They operate Vee‐Ballt
control valves, butterfly valves, built‐in turbine valves, louvers, dampers and similar equipment. They are suitable for
either push‐down‐to‐close (PDTC) or push‐down‐to‐open (PDTO) applications and are available in sizes 30, 40 and 60
to provide 54 mm (2.125 inch), 64 mm (3.5 inch) and 105 mm (4.125 inch) travel, respectively.
Do not install, operate, or maintain a 656 actuator without being fully trained and qualified in valve, actuator, and
accessory installation, operation, and maintenance. To avoid personal injury or property damage, it is important to
carefully read, understand, and follow all the contents of this manual, including all safety cautions and warnings. If you
have any questions about these instructions, contact your Emerson sales office
or Local Business Partner before
proceeding.
Instruction Manual
D100304X012
656 Actuator
June 2017

Summary

Introduction

Scope of Manual

Manual content overview, including installation, maintenance, and parts information.

Description

Explains Fisher 656 diaphragm actuators, their operation, applications, and available sizes.

Principle of Operation

Specifications

Details technical specifications for the 656 actuator, including pressure and travel limits.

Maximum Pressure Limitations

Details pressure limits for actuator sizing, excess diaphragm, and casing to prevent damage.

Installation

Adjustment

Outlines checking actuator travel, friction, and PDTC/PDTO action after installation.

Maintenance

Disassembly

Provides step-by-step instructions for safely disassembling the 656 diaphragm actuator.

Assembly

Parts Ordering

Parts List

Lists all available parts for the 656 actuator with corresponding keys and descriptions.

Emerson Fisher 656 Specifications

General

Brand	Emerson
Model	Fisher 656
Category	Controller
Language	English