Masoneilan 496-257 Dual SPDT Mechanical Valve Position Limit Switch
The Masoneilan 496-257 Valve Position Limit Switch is designed to provide reliable electrical indication of valve position in industrial process control systems.
- Two Mechanical SPDT Switches Switching Configuration
- Adjustable Cam Mechanism Switch Actuation
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- Fast dispatchAustralia & worldwide
- Technical supportTalk to an engineer
- 1 YearWarranty
Product Overview
The Masoneilan 496-257 Valve Position Limit Switch is designed to provide reliable electrical indication of valve position in industrial process control systems. Manufactured under the Masoneilan brand by Baker Hughes, this electromechanical limit switch uses two independently actuated single-pole, double-throw (SPDT) microswitches to detect predefined valve travel positions. Its adjustable cam mechanism enables switching at selected points during actuator movement, supporting accurate open and closed position indication, automated monitoring, and dependable industrial valve operation.
Part of the Masoneilan 496 Series, the 496-257 features an explosionproof enclosure designed for appropriately certified hazardous-area installations. Its corrosion-protected aluminium housing, stainless steel shaft, adjustable cams, and IP66/IP67 enclosure protection support reliable operation in demanding industrial environments. The switch can be mounted on compatible rotary valves or linear actuators using suitable mounting linkages. It is suitable for oil and gas processing, petrochemical facilities, power generation, water treatment, and industrial process automation.
Technical Specifications
|
Specification |
Value |
|---|---|
|
Product Name |
Dual SPDT Mechanical Valve Position Limit Switch |
|
Manufacturer / Brand |
Masoneilan / Baker Hughes |
|
Model |
496-257 |
|
Series |
496 |
|
Product Type |
Electromechanical Valve Position Limit Switch |
|
Switching Configuration |
Two Mechanical SPDT Switches |
|
Number of Microswitches |
2 |
|
Contact Configuration |
Single Pole, Double Throw |
|
Operating Principle |
Mechanical Cam-Actuated Switching |
|
Switch Actuation |
Adjustable Cam Mechanism |
|
Enclosure Configuration |
Explosionproof, Gas and Dust |
|
Standard Housing Material |
Corrosion-Protected Aluminium |
|
Housing Finish |
Epoxy or Polyurethane Paint |
|
Optional Housing Material |
316L Stainless Steel |
|
Shaft Material |
Stainless Steel |
|
O-Ring Material |
Buna-N |
|
Enclosure Protection |
IP66 / IP67 |
|
Maximum Rotary Travel |
90° |
|
Supported Linear Travel |
12–102 mm with Suitable Linkage |
|
Electrical Connection |
3/4 Inch NPT |
|
Switching Contacts |
Silver-Plated |
|
Operating Temperature |
−55°C to +85°C, Depending on Switch and Approval |
|
Switching Repeatability |
0.2% |
|
Rotary Differential Gap |
Approximately 1.5% of Full Scale |
|
Hazardous-Area Protection |
Explosionproof Configuration, Code 57 |
|
Certifications |
Subject to Applicable Unit Nameplate and Approval |
|
Compatible Equipment |
Pneumatic Valve Actuators and Control Valve Assemblies |
|
Application Scope |
Valve Position Indication and Industrial Automation |
|
Related Positioner Models |
SVI2-21113111, SVI2-21123121, SVI2-21113121, SVI2-22113121 |
|
Condition |
New |
|
Warranty |
1 Year |
Key Features
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Dual electromechanical SPDT microswitches for detecting two selected valve travel positions.
-
Adjustable mechanical cams for configuring switching points.
-
Provides electrical open and closed position indication to compatible control systems.
-
Explosionproof enclosure configuration for appropriately certified hazardous environments.
-
IP66/IP67 protection against dust and water ingress.
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Durable corrosion-protected aluminium housing for industrial applications.
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Stainless steel operating shaft for reliable mechanical coupling.
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Silver-plated electrical contacts for dependable switching.
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Supports rotary actuator travel up to 90 degrees.
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Compatible with selected linear valve installations through appropriate linkage arrangements.
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Mechanical switching operation without requiring a dedicated electronic proximity sensor.
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Suitable for integration with PLCs, distributed control systems, and industrial alarm circuits.
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Adjustable switching positions for different actuator configurations.
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Supports valve position monitoring during automated process operations.
-
Suitable for industrial control valve maintenance and replacement applications.
Typical Applications
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Industrial valve open and closed position indication
-
Pneumatic control valve automation
-
Ball and butterfly valve position monitoring
-
Linear control valve travel indication
-
Oil and gas production and processing facilities
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Chemical and petrochemical plants
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Petroleum refining installations
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Power generation and utility systems
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Water and wastewater treatment facilities
-
Industrial manufacturing machinery
-
PLC and distributed control system feedback
-
Industrial valve monitoring and alarm systems
Shipping & Support
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Fast dispatch – Australia & Worldwide Shipping
-
Technical assistance available
-
1-year warranty
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