Siemens 73N12F - User Manual

INSTALLATION AND SERVICE INSTRUCTION
Siemens
Energy & Automation
SD73
Rev 13
September 2008
Supersedes Rev 12
MODEL 73N BUILT-IN VALVE POSITIONER
The Model 73N is a Built-in Valve Positioner which is mounted directly on the topworks of a valve. It is capable of
utilizing the full force of its air supply to drive the piston or diaphragm, in a pneumatic actuator, to a position called
for by the control instrument. The positioner incorporates a single-axis force-balance principle of operation to insure
accurate and stable positioning of a control valve.
MODEL DESIGNATION
73N 12 F
Basic Model Number
Input Span – psig
Special Feaures
F — Fast response
R — Reverse acting
E — Tapped Exhaust
USM — U.S. Electrical Motors Type
Fast Response: The fast response positioner is used on actuators with large volume topworks requiring a fast
response action. Due to increased pilot plunger travel and larger ports in the fast response positioner, greater filling
and exhausting capacities result. This permits a quicker response to a change in control conditions, plus increased
speed of valve operation.
Tapped Exhaust: The Model 73N Positioner can be ordered with a tapped exhaust port. This feature permits piping
of the pilot exhaust to a safe atmosphere on applications where noxious gases are used as a control medium instead
of air.
USM: On actuators with small topworks and a low volume, a special hi-response positioner may be used. This
positioner is denoted by the letters USM in the model number. There is no bleed on this model due to the low
volume. A special valve plunger is used to ensure fast response for close control.
GENERAL SPECIFICATIONS
Instrument Input Pressure Range...................3-15, 3-9, 9-15, and 3-27 psig
Supply Pressure
Minimum................................................3 psi above required actuator pressure
Maximum ...............................................100 psi
Air Consumption ...........................................0.25 SCFM (in balance condition with 20 psi supply and 9 psi dead
ended output)
Valve Travel
Minimum................................................1/4"
Maximum ...............................................4"
Ambient Temperature Limits ........................-40°C to +82°C (-40°F to +180°F)

Summary

MODEL 73 N BUILT-IN VALVE POSITIONER

Model Designation

Details the identification system for the 73N model.

Special Features

Describes optional features like fast response, tapped exhaust, and USM.

General Specifications

Lists key operational and performance parameters of the positioner.

INSTALLATION AND CONNECTIONS

Installation Safety Precautions

Highlights crucial safety warnings during installation, including temperature and pressure limits.

Pneumatic Connections Guide

Provides instructions and recommendations for pneumatic line connections.

Instrument Air Requirements

Specifies the necessary quality standards for instrument air supply.

POSITIONER ADJUSTMENT

Zero Adjustment Procedure

Explains how to perform the zero adjustment on the positioner.

Range Spring Selection

Guides users on selecting the appropriate range spring based on valve stroke and pressure span.

MAINTENANCE GENERAL

Cleaning Procedure

Outlines the steps for cleaning the valve plunger without full disassembly.

Disassembly Steps

Details the procedure for taking apart the positioner.

Assembly Steps

Provides instructions for reassembling the positioner after maintenance.

CUSTOMER AND PRODUCT SUPPORT

Contact Information

Lists contact details and resources for obtaining technical support and service.

WARRANTY

PARTS LIST

Siemens 73N12F Specifications

General

Brand	Siemens
Model	73N12F
Category	Valve Positioners
Language	English