Advanced Sensing Technology for Enhanced Safety Performance

DPST Switch Position Monitoring

At the heart of the SV27 Series is a safety-rated Double-Pole Single-Throw (DPST) switch that continuously monitors the valve's internal operating position. This directly operated, force-guided positive-break status switch provides electrical feedback to control systems, confirming that valve internals have shifted properly during each actuation cycle. This critical safety feature enables diagnostic coverage of up to 90% when the safety switch status is actively monitored by external safety systems.   

Poppet Construction for Superior Reliability

The SV27 valves utilize a robust poppet design that delivers near-zero leakage performance while maintaining exceptional dirt tolerance. This wear-compensating construction ensures quick response times and high flow capacity even in demanding industrial environments where contamination and particulate matter are present. The poppet seat design provides positive sealing that prevents unintended cylinder movement during extended holding periods.     

Comprehensive Safety Certifications and Performance Ratings

TÜV Rheinland Functional Safety Certification

ROSS SV27 Series valves are certified by TÜV Rheinland of North America in accordance with the most rigorous international safety standards: 

• IEC 61508 and IEC 61511: Safety Integrity Level 2 (SIL 2) for single valve applications with Hardware Fault Tolerance (HFT) = 0  
• SIL 3 certification for redundant applications with HFT ≥ 1 
• ISO 13849-1:2015: Performance Level c (PL c) for Category 2 applications; Performance Level e (PL e) for Category 3 applications   

Functional Safety Data

The valves demonstrate exceptional reliability metrics critical for safety system design: 

• B10D Value: 20,000,000 cycles (representing the number of cycles until 10% dangerous failure probability) 
• PFHᴅ (Probability of dangerous Failure per Hour):
  • Single configuration: 2.35 × 10⁻⁷ 
  • Redundant configuration: 2.47 × 10⁻⁸ 
• MTTFᴅ (Mean Time To dangerous Failure):
  • Single: 98.15 years (nop: 7360) 
  • Redundant: 100 years (nop: 7360) 

Dual Configuration Options for Flexible Safety System Design

Category 2 Single Valve Configuration

Single SV27 valves provide Performance Level c (PL c) safety protection suitable for applications requiring moderate risk reduction. This configuration is ideal for load holding functions where a single point of control is acceptable based on risk assessment outcomes. The single valve design offers a compact footprint and economical solution while maintaining full position sensing capabilities.      

Category 3 Redundant Valve Configuration

For high-risk applications demanding maximum safety integrity, the redundant SV27 configuration achieves Category 3 safety performance with Performance Level e (PL e). This dual-valve arrangement provides critical redundancy—if one valve element experiences a fault, the second valve maintains the safety function, preventing dangerous load movement. Redundant configurations are essential for applications involving overhead loads, elevated work platforms, or processes where valve failure could result in serious injury.       

Versatile Actuation Methods for System Integration

Solenoid Pilot Controlled Valves

Solenoid-actuated SV27 models integrate seamlessly with electrical control systems, offering:

• Voltage options: 24 VDC, 110-120 VAC (50/60 Hz), and 230-240 VAC configurations 
• Continuous duty rating for extended operation without thermal degradation 
• Power consumption: 6-14 watts depending on body size and pilot style 
• LED indicators on solenoid pilots for visual operational verification 
• Manual override capability with flush, non-locking button (Pacer style pilots) 

Body size 3/4" models utilize CNOMO Style Pilots, while 1-1/4" and larger sizes employ higher-capacity Pacer Style Pilots. Each solenoid connects via 3-pin MINI connectors for reliable electrical interface.  

Pressure Controlled Valves

Pneumatic-actuated models respond directly to pilot air pressure signals, making them ideal for:

• All-pneumatic safety circuits without electrical dependencies  
• Hazardous location applications where electrical spark risks must be eliminated  
• Simple retrofit installations into existing pneumatic systems 

Pressure-controlled valves feature a 1/4" signal port and require pilot pressure equal to or greater than inlet pressure to ensure reliable actuation.  

Technical Specifications and Operating Parameters

Flow Performance Characteristics

The SV27 Series provides exceptional flow capacity across multiple body sizes: 

Operating Environment

• Ambient Temperature Range: 40° to 120°F (4° to 50°C)  
• Media Temperature Range: 40° to 175°F (4° to 80°C)  
• Operating Pressure: 40 to 150 psig (2.8 to 10.3 bar)  
• Flow Media: Filtered air (5-micron filtration recommended) 
• Mounting Orientation: Any position, preferably vertical 
• Pilot Pressure Requirement: Must equal or exceed inlet pressure 

Materials of Construction

• Valve Body: Cast aluminum for corrosion resistance and lightweight durability  
• Poppet: Acetal and stainless steel for wear resistance  
• Seals: Buna-N standard; Fluorocarbon available for chemical compatibility  

Electrical Interface and Monitoring Capabilities

Safety Switch Specifications

The integrated DPST switch provides dual-channel monitoring with these electrical characteristics: 

• Maximum Rating: 2.5 A at 120 VAC  
• Minimum Rating: 50 mA at 24 VDC  
• Switch Life Expectancy: Rated for over 15 million electrical cycles 
• Connection: 5-pin M12 connector (industry-standard format)  
• Output Configuration: Dual normally-open (NO) and normally-closed (NC) contacts  

The DPST switch actuates whenever the valve shifts from its normal home position, providing positive confirmation of valve state to safety PLCs or relay logic systems. This critical feedback enables fault detection and system diagnostics that meet the requirements for high diagnostic coverage in functional safety applications.    

Connector Systems

Pre-wired connector kits simplify installation and reduce wiring errors: 

• Cable lengths: 4 meters (13.1 ft) and 10 meters (32.8 ft) options 
• Configuration: Flying lead terminations for panel connection 
• Quantity: Redundant valves require two complete connector kits 

Essential Accessories for Complete Safety Systems

Energy Release Verification Devices

Confirming that trapped pressure has been safely exhausted is critical for worker safety during maintenance. ROSS offers two verification methods: 

Pneumatic Visual Pressure Indicators (Model 988A30)

• Pop-up pin design provides visual confirmation of depressurization 
• 1/8" NPT connection to pressure verification port 
• No electrical power required—purely mechanical operation 

Electrical Pressure Switches (Model 586A86)

• Factory preset to 5 psi (0.3 bar) falling pressure 
• DIN EN 175301-803 Form A connector with NO/NC contacts 
• Integrates with safety control systems for automatic monitoring 
• 1/8" NPT installation in pressure sensing port or downstream location 

Manual Override Kits

For valve testing and emergency manual operation, ROSS provides three override configurations: 

1. Flush Button Kit (792K87): Locking-type metal button for permanent activation
2. Extended Button Kit (791K87): Non-locking spring-return for momentary operation
3. Extended Button with Palm Kit (984H87): Large surface area for easy activation with personal protective equipment

Indicator Light Kits

Visual confirmation of solenoid energization aids troubleshooting and operational verification. Available for 24 VDC (862K87-W), 110-120 VAC (862K87-Z), and 230 VAC (862K87-Y) systems. 

Critical Industrial Applications

Load Holding for Overhead Lifts

In applications such as automotive lifts, scissor lifts, and elevated work platforms, SV27 valves prevent dangerous drops if pneumatic supply is lost or hoses rupture. The near-zero leakage poppet design maintains position without drift, even during extended work periods lasting hours or entire shifts.    

Press and Forming Operations

Manufacturing presses require precise cylinder positioning during forming cycles. SV27 valves maintain exact pressure and position, ensuring consistent part quality and preventing workpiece damage from unintended movement. The position sensing capability allows press control systems to verify proper valve operation before each cycle begins.   

Counterbalance and Safety Catcher Systems

Vertical pneumatic cylinders handling heavy tooling or components benefit from SV27 load holding to prevent gravity-induced motion during power failures or emergency stops. The valves can be integrated with mechanical safety catchers to provide multi-layer protection in high-risk applications.  

Material Handling and Conveyor Systems

Automated material handling systems use SV27 valves to hold gates, diverters, and positioning actuators in safe states during normal operation and emergency conditions. The sensing feedback integrates with PLC safety logic to confirm all actuators are in expected positions before conveyor restart.   

Integration with Safety Control Systems

SISTEMA Library Support

ROSS provides downloadable SISTEMA (Safety Integrity Software Tool for the Evaluation of Machine Applications) library files for the SV27 Series. This invaluable resource enables safety engineers to accurately calculate Performance Levels and verify that complete safety systems meet ISO 13849-1 requirements.     

External Monitoring Requirements

While the SV27 valves provide position sensing capabilities, they are designed for integration with external monitoring systems that process the sensor signals and provide safety logic control. Proper monitoring systems must be capable of:  

• Detecting single faults within the valve mechanism  
• Inhibiting further machine operation when faults are detected  
• Initiating safe shutdown sequences based on valve feedback  
• Recording fault events for maintenance and compliance purposes 

Recommended Testing Intervals

ROSS recommends testing switch function and seal integrity for load holding valves every 8 hours during operation to ensure continued safety performance. Minimum operational frequency of once per month is specified to maintain proper internal component function.  

Design Considerations and Best Practices

Filtration Requirements

Although SV27 valves feature dirt-tolerant poppet construction, optimal performance and service life require proper air preparation. ROSS recommends 5-micron filtration for normal applications to prevent contaminant buildup that could eventually compromise sealing surfaces or switching mechanisms. 

Avoiding Intake and Exhaust Restrictions

Supply line restrictions can reduce pressure below minimum valve operating requirements, causing erratic operation. Similarly, exhaust port restrictions increase back pressure and adversely affect valve response. Any exhaust silencers must maintain flow capacity at least equal to valve exhaust capacity and resist contamination that would increase pressure drop. 

Port Thread Options

SV27 valves are available with NPT (National Pipe Thread) or G (ISO 228 parallel) thread standards to accommodate regional preferences and existing system configurations. Proper thread sealant application and torque are essential to prevent leakage and ensure pressure ratings are maintained.  

Complete Model Number Configuration System

The SV27 Series uses a comprehensive alphanumeric designation system that specifies all valve characteristics: 

Format: SV27 - [Port Thread] - [Valve Function] - [Body/Port Size] - [Actuation] - [Schematic] - [Voltage]

Example Interpretations:

• SV27NC115508CSAA1D: Single valve (11), 3/4" body, 1/2" × 1/2" ports, solenoid controlled (8CS), 24 VDC (1D) 
• SV27DC555508CSAA1A: Redundant valve (55), 3/4" body, 1/2" × 1/2" ports, solenoid controlled (8CS), 120 VAC (1A) 

This systematic nomenclature ensures accurate specification and ordering for the precise valve configuration required for each application. 

Comprehensive Technical Support Resources

Downloadable CAD Models

ROSS provides detailed 3D CAD models in multiple formats for the SV27 Series, enabling precise integration into machine designs and assembly documentation. These models include accurate port locations, mounting hole patterns, and overall envelope dimensions.  

Installation and Maintenance Documentation

Complete installation instructions, maintenance procedures, and troubleshooting guides accompany each valve. These resources ensure proper installation practices that maintain safety certifications and warranty coverage. 

Technical Support Access

ROSS technical services team provides expert application support for safety system design, valve selection, and integration questions. Contact information: 1-888-835-7677.  

Compliance with Global Safety Standards

Machinery Directive 2006/42/EC

SV27 Series valves meet European machinery safety requirements, supporting compliance for equipment exported to EU markets.   

OSHA Requirements

The valves align with OSHA 1910.147 (Control of Hazardous Energy - Lockout/Tagout) when integrated into properly designed safety systems.  

CSA/UL Certification

Comprehensive testing and certification ensures compliance with North American safety requirements.  

EAC Declaration

Certification for Eurasian Economic Union markets (Russia, Kazakhstan, Belarus, Armenia, Kyrgyzstan).  

Why Choose ROSS SV27 Series for Your Safety Applications

Proven Poppet Technology Heritage

The SV27 builds upon ROSS's decades of experience with the Series 27 valve family, incorporating field-proven poppet technology that has protected workers and equipment in thousands of industrial facilities worldwide. This heritage ensures reliability based on real-world performance, not just laboratory testing.  

Comprehensive Safety Certification

With TÜV Rheinland certification to the latest IEC and ISO standards, SV27 valves provide documented proof of functional safety performance that satisfies insurance requirements, regulatory compliance, and corporate safety policies.   

Integrated Sensing Eliminates External Components

The built-in DPST position switch eliminates the need for separate proximity sensors, reducing installation complexity, potential failure points, and overall system cost. This integrated approach also ensures proper sensor alignment and eliminates mechanical damage risks associated with external sensors.   

Application Flexibility

Whether your application requires single-valve Category 2 protection or redundant Category 3 safety, solenoid or pneumatic actuation, NPT or G threads, the SV27 Series offers configurations to match your exact requirements without compromise.   

Download Complete Product Catalog

Access the full technical specifications, dimensional drawings, ordering information, and application examples in the complete SV27 Series catalog PDF. This comprehensive resource includes:

• Detailed specifications for all body sizes and configurations
• Dimensional drawings with mounting hole patterns
• Complete model number configurator and ordering guide
• Electrical connection diagrams and switch pinout details
• Accessory compatibility charts
• Installation and maintenance recommendations
• Safety certifications and compliance documentation
• Application circuit examples with integration guidance

The catalog provides everything safety engineers, machine designers, and maintenance professionals need to specify, order, install, and maintain SV27 Series valves for critical load holding applications.

For additional product information, custom configurations, or application assistance, visit the SV27 Series product page or contact ROSS Controls technical support at 1-800-GET-ROSS (1-800-438-7677).

About ROSS Controls

ROSS Controls is the global leader in pneumatic and hydraulic safety solutions, providing advanced valves and safety systems that protect workers and equipment in industrial environments worldwide. With over 50 years of safety innovation, ROSS pioneered many of the control-reliable valve technologies that have become industry standards. The company maintains manufacturing facilities in North America, Europe, South America, and Asia, with technical support available globally.

ROSS products are certified to the most rigorous international safety standards, including ISO 13849, IEC 61508, and IEC 61511, with third-party validation by TÜV Rheinland and other recognized testing laboratories. The company's commitment to functional safety excellence makes ROSS the preferred partner for safety-critical applications in automotive, packaging, material handling, food processing, and general industrial manufacturing.    

Global Headquarters:
950 Woodward Heights
Ferndale, Michigan 48220 USA
Tel: +1-248-764-1800
www.rosscontrols.com