Honeywell ML7425A Series - User Manual

PRODUCT DATA
® U.S. Registered Trademark
Copyright © 1999 Honeywell Inc. • All Rights Reserved
ML7425A,B
Spring Return Electric Linear
Valve Actuator
APPLICATION
The ML7425A,B Spring Return Electric Linear Valve
Actuators are modulating control actuators used with controls
that provide an analog output of 0 to 10 Vdc or 2 to 10 Vdc.
These actuators operate standard Honeywell valves in
Heating, Ventilating, and Air Conditioning (HVAC)
applications. An internal selector plug can be used to reverse
the direction of action.
FEATURES
• Quick and easy installation.
• No separate linkage required.
• ML7425A extends actuator stem on power failure;
ML7425B retracts actuator stem on power failure.
• Conduit connector is standard.
• No adjustments required.
• True spring return on power failure.
• Accurate valve positioning.
• Low power consumption.
• High close-off ratings.
• Force-limiting end switches.
• 0 to 10 Vdc or 2 to 10 Vdc signal input.
• Position feedback signal.
• Direct/reverse action.
• Fail-safe position selection.
• Synchronous motor.
• Corrosion resistant design.
• Maintenance free.
Contents
Application ....................................................................... 1
Features ........................................................................... 1
Specifications................................................................... 2
Installation ........................................................................ 3
Operation ......................................................................... 7
Checkout .......................................................................... 8
Ordering Information ........................................................ 8
63-2518-3

Honeywell ML7425A Series Specifications

General

Brand	Honeywell
Model	ML7425A Series
Category	Controller
Language	English

Summary

Features

Application Overview

Technical Specifications

Electrical Ratings

Details power input voltage, frequency, and consumption.

Signal Inputs

Specifies the analog input signal types and ranges supported.

Output Resistance and Load

Defines signal source resistance and maximum load.

Actuator Performance

Details stem force, stroke, and run time specifications.

Environmental Ratings

Lists ambient temperature, maximum valve medium, and humidity limits.

Close-off Pressure Ratings

Specifies pressure handling capabilities with various valve types.

Installation Guide

Product Installation Precautions

Important safety and procedural instructions before installing the product.

Location and Mounting

Guidelines for actuator placement and physical attachment to the valve.

Available Accessories

Lists optional components that can be used with the actuator.

Wiring and Operation

Wiring Diagrams and Instructions

Details on connecting power and control wires, including typical hookups.

Selector Plug Functions

Explanation of W1, W2, and W3 selector plugs for configuration.

Auxiliary Components

Information on using auxiliary potentiometers and switches.

Signal Input Configuration

How to set the analog input signal range (0-10 Vdc or 2-10 Vdc).

Signal Input Failure Modes

Settings for actuator behavior during loss of input signal.

Output Signal Feedback

Details on the analog output signal representing stem position.

Actuator Override Function

How to force the actuator into an end position for freeze protection.

Direction of Action

How to change the stem extension/retraction response to control signals.

Checkout and Ordering

Direct Checkout Procedure

Steps to verify actuator operation without a controller.

Controller Checkout Procedure

Steps to verify actuator operation using a connected controller.

Ordering Information

Guidance on purchasing replacement and modernization products.