ROSS M35 Series Safe Exhaust Double Valve Interactive 3D Product Demonstration with EEZ-ON Soft-Start Comparison

M35 Series Features and Technical Highlights

Redundant Control for Category 4 PL e Safety

The M35 Series achieves Category 4, Performance Level e per ISO 13849-1:2015 and SIL 3 per IEC 62061:2005 through its inherently redundant dual poppet architecture. The valve contains two independent valve elements — each actuated by its own dedicated solenoid — that operate synchronously to control supply air and safe exhaust functions. In the event of a single fault in either element, the system continues to maintain the safe state, and the monitoring circuitry detects the discrepancy on the next operational cycle. This design eliminates single points of failure from the pneumatic safety circuit and meets the stringent requirements of the most demanding machine safety standards worldwide.

The B10D life rating of 25,000,000 cycles, combined with a PFHD of 7.71 × 10⁻⁹ and MTTFD of 301.9 years (at nop of 662,400 cycles per year), demonstrates the long-term reliability required for continuous production environments. These figures are verified and available in the ROSS Controls SISTEMA library for direct import into your ISO 13849-1 safety calculations.

External Monitoring with Solid State Pressure Sensors

Each M35 valve incorporates two PNP solid state pressure sensors — one per valve element — providing dynamic, cyclical, external monitoring of the valve state. These sensors draw less than 23 mA each and connect via the two 5-pin M12 connectors on the valve body. By reading the state of both pressure sensors simultaneously, the customer-supplied safety monitoring system can verify that each valve element has reached its commanded position and that no discrepancy exists between the two channels.

The monitoring scheme is classified as dynamic and cyclical, requiring a minimum operation frequency of once per month to maintain diagnostic coverage. The pressure switch rating of 5 amps at 250V AC or 5 amps at 30V DC ensures compatibility with a wide range of safety PLCs and safety relay modules. The overall diagnostic coverage achieved by this arrangement supports the Category 4 PL e and SIL 3 safety integrity ratings.

Optional EEZ-ON Soft-Start Module

The optional EEZ-ON Soft-Start module mounts directly onto the M35 valve body and provides controlled, gradual pressurization of the downstream pneumatic circuit after a safe exhaust event. When the system restores supply pressure, the EEZ-ON module allows outlet pressure to increase slowly until it reaches approximately 50% of the inlet supply pressure; it then opens fully to allow unrestricted flow. This two-stage pressurization approach prevents sudden actuator movement that could injure personnel or damage tooling, making it particularly valuable in applications where residual downstream volume is large or where actuator speed during re-energization poses a hazard.

The Soft-Start module reduces the flow Cv in the 1-to-2 direction slightly — from 4.3 (4200 Nl/min) without Soft-Start to 4.1 (4000 Nl/min) with Soft-Start — a minor trade-off for the significant safety benefit of controlled re-pressurization. The 3D interactive PDF allows users to visually compare the two valve configurations and understand the physical addition the Soft-Start module represents.

PTFE Backup Piston Rings and Poppet Design

The M35 employs a dual poppet design with PTFE backup piston rings for enhanced endurance. The poppet construction — combining acetal and stainless steel poppets with Buna-N seals — is inherently tolerant of particulate contamination in the compressed air supply, compensates for seal wear over time, and operates reliably whether the air supply is lubricated or non-lubricated. The PTFE backup rings provide long-term wear compensation that maintains consistent sealing performance throughout the rated B10D life of 25,000,000 cycles.

The cast aluminum body keeps valve weight low while providing structural rigidity for inline mounting. The dual poppet design also contributes to the high flow capacity of the M35 — 7.6 Cv (7400 Nl/min) in the 2-to-3 (exhaust) direction — enabling rapid depressurization of large downstream volumes. LED indicators on the valve body provide immediate visual status indication for maintenance personnel during commissioning and troubleshooting.

Technical Specifications and Performance Data

Operating Parameters and Pressure Ratings

• Valve function: 3/2 Normally Closed, Safe Exhaust Control Reliable Double Valve
• Construction: Dual Poppet design with acetal and stainless steel poppets
• Mounting: Inline — modular/threaded, any orientation (preferably vertical)
• Connections: NPT or G threaded ports in 1/2 and 3/4 inch sizes
• Operating pressure: 30–150 psig (2–10 bar)
• Ambient temperature: 40–120°F (4–50°C)
• Media temperature: 40–175°F (4–80°C)
• Flow media: Compressed air per ISO 8573-1 Class 7:4:4
• Minimum operation frequency: Once per month
• Vibration tested to DIN EN 60068-2-6

Electrical Specifications

• Solenoid voltage: 24V DC, 2.0 watts each, continuous duty (2 solenoids total)
• Electrical connection: Two 5-pin M12 connectors
• Enclosure rating: IP 65 per IEC 60529 (DIN 400 50)
• Pressure sensors: 2 per valve, PNP solid state, < 23 mA each
• Pressure switch rating: 5 amps at 250V AC or 5 amps at 30V DC
• LED indicators: Included for status display
• Actuation: Solenoid pilot operated with air-assisted spring return; one solenoid per valve element, both operated synchronously

Flow Capacity and Port Sizes

• Port sizes: 1/2 inch and 3/4 inch inlet/outlet
• Flow Cv (1-2 direction) with built-in silencer — With Soft-Start: 4.1 (4,000 Nl/min)
• Flow Cv (1-2 direction) with built-in silencer — Without Soft-Start: 4.3 (4,200 Nl/min)
• Flow Cv (2-3 exhaust direction): 7.6 (7,400 Nl/min) for both models
• Weight with EEZ-ON Soft-Start module: 6.5 lb (2.9 kg)
• Weight without Soft-Start: 4.2 lb (1.9 kg)
• Silencer options: Built-in module or threaded flange
• Body material: Cast Aluminum; Poppets: Acetal and Stainless Steel; Seals: Buna-N

Functional Safety Data

• Safety Category: Category 4, Performance Level e (PL e) per ISO 13849-1:2015
• Functional Safety: SIL 3 per IEC 62061:2005
• B10D: 25,000,000 cycles
• PFHD: 7.71 × 10⁻⁹
• MTTFD: 301.9 years (nop: 662,400 cycles per year)
• SISTEMA Library: Available for ISO 13849-1 safety calculations
• Certifications: DGUV (HM 230177), CE, EAC, CSA/UL

Applications and Industries

General Manufacturing and Assembly Lines

The M35 Series is ideally suited for general manufacturing and assembly operations where machine zones must be safely isolated during maintenance, tooling changes, or jam clearance. When a maintenance technician requires access to a guarded machine zone, the M35 responds to the safety system’s shut-off command by simultaneously stopping supply air and exhausting all residual downstream pneumatic energy. This eliminates the risk of unexpected actuator movement during access, satisfying the safe energy control requirements of OSHA lockout/tagout regulations and EN ISO 13849-1 safety circuit requirements.

The inline modular mounting configuration simplifies integration into existing pneumatic panel layouts, and the NPT or G threaded port options accommodate both North American and international installations. The M35 can be specified as a standalone safe exhaust valve or incorporated into a complete Safe Air Entry System Assembly together with an L-O-X lockout valve for comprehensive pneumatic energy isolation.

Automotive Production and Robotics

Automotive assembly plants and robotic workcells represent one of the highest-demand environments for safe exhaust valve technology. The M35 Series provides the Category 4 PL e safety level required by many automotive OEM machine standards for pneumatic energy control in robotic cells, spot welding systems, press lines, and material handling equipment. Its compact inline design allows installation close to the machine zone being controlled, minimizing residual downstream volume and reducing the time required to achieve safe exhaust conditions.

The cyclical monitoring architecture of the M35 is compatible with modern safety PLC systems from leading automation suppliers, simplifying integration into robot controller safety I/O circuits. The 24V DC solenoid voltage and M12 connectors align with standard automotive plant electrical infrastructure, reducing wiring complexity and commissioning time.

Packaging and Food Processing

In packaging machinery and food processing equipment, the M35 with EEZ-ON Soft-Start is particularly valuable because re-pressurization of the pneumatic circuit must be controlled to prevent sudden actuator strokes that could damage product, jam packaging lines, or injure personnel performing product changeover tasks. The EEZ-ON module’s gradual pressure ramp — rising slowly to approximately 50% of inlet pressure before opening fully — gives actuators a smooth, controlled restart that protects both product quality and operator safety.

The IP 65 enclosure rating and Buna-N seals are compatible with the washdown environments common in food processing facilities. The valve’s tolerance of ISO 8573-1 Class 7:4:4 compressed air quality is achievable with standard industrial compressor systems, and the option for non-lubricated operation eliminates concerns about oil contamination of air circuits near food contact surfaces.

Safety Standards and Compliance

The ROSS Controls M35 Series is designed, tested, and certified to meet the most rigorous international machine safety standards applicable to pneumatic energy control components. The valve achieves Category 4, Performance Level e per ISO 13849-1:2015 — the highest achievable safety category for control system architecture — and SIL 3 per IEC 62061:2005, confirming suitability for the most demanding functional safety applications. DGUV certification (HM 230177) confirms independent third-party verification by the German Social Accident Insurance organization, one of the most respected notified bodies for safety component certification in Europe. CE marking confirms compliance with applicable European Union directives, while EAC certification covers Eurasian Economic Union requirements. CSA/UL certification addresses North American market requirements, making the M35 a globally certifiable component for multinational machine builders.

The valve is vibration tested to DIN EN 60068-2-6, confirming suitability for installation on or near vibration-generating equipment. The IP 65 enclosure rating per IEC 60529 ensures protection against dust ingress and low-pressure water jets, supporting installation in production environments without additional protective enclosures. The compressed air quality requirement of ISO 8573-1 Class 7:4:4 is compatible with standard industrial compressed air systems and does not require special filtration or drying beyond typical practice. Compliance with OSHA 29 CFR 1910.147 (Control of Hazardous Energy) requirements is supported when the M35 is incorporated into a properly designed pneumatic energy isolation system including an L-O-X lockout valve.

How to Use the M35 Series 3D Interactive PDF

Comparing Models with and without Soft-Start

The M35 Series 3D interactive PDF provides an intuitive model selection interface that allows users to switch between the two primary valve configurations: "Valve with Soft-Start" and "Valve without Soft-Start." By selecting either configuration from the interactive menu within the PDF, the 3D model updates to display the chosen variant. This toggle capability allows direct visual comparison of the two configurations — including the physical addition of the EEZ-ON module on the inlet side of the valve body — helping engineers confirm whether the soft-start variant fits within the available space envelope of their machine design.

The 3D PDF was created by 3D Sales Technologies GmbH using professional CAD-to-3D-PDF conversion technology. It is designed to be viewed in Adobe Acrobat Reader DC or Adobe Acrobat Pro, which provide full support for the interactive 3D features. Ensure that Adobe Acrobat’s 3D content rendering is enabled in the Preferences menu to activate all interactive features of the document.

Exploring Internal Components and External Features

Within the 3D viewer, users can freely rotate the valve model by clicking and dragging, zoom in using the scroll wheel or pinch gesture, and pan across the model to inspect specific features. Key external features visible in the 3D view include the M12 electrical connectors, NPT/G threaded port locations, LED indicator windows, solenoid coil housings, and the modular silencer. The dual poppet valve body structure is clearly visible in the overall form of the product.

The 3D navigation toolbar within the PDF provides additional view controls including standard orthographic projections (front, top, side), perspective toggle, and measurement tools where applicable. Users can also use preset views if provided in the document to jump to specific orientations that highlight particular features of the valve. These capabilities make the 3D PDF a powerful tool for both engineering evaluation and customer presentations.

Why Choose ROSS Controls

Engineering Heritage and Product Quality

ROSS Controls was founded in 1921 and has more than 100 years of experience designing and manufacturing precision pneumatic valves and safety components for industrial applications worldwide. The M35 Series represents the current state of the art in ROSS safe exhaust valve technology, incorporating more than a century of learning about pneumatic circuit design, sealing technology, and machine safety requirements. The M35 is not simply a valve — it is engineered as part of a broader safe pneumatic energy control system that includes integration with the ROSS L-O-X lockout valve in Safe Air Entry System Assemblies, providing a complete, validated solution for pneumatic energy isolation from a single manufacturer.

ROSS Controls manufactures its valves to rigorous quality standards and subjects the M35 to independent third-party certification by DGUV, CSA/UL, and other recognized certification bodies. The functional safety data provided — including B10D, PFHD, and MTTFD values — is based on documented testing and calculation per the methods specified in ISO 13849-1:2015 and IEC 62061:2005, not estimates. PTFE backup piston rings and precision-machined acetal and stainless steel poppets ensure that the M35 maintains its performance characteristics throughout the rated service life of 25,000,000 cycles.

Global Support and Technical Resources

ROSS Controls supports customers throughout the world with application engineering expertise, product literature, 3D CAD models, and functional safety calculation resources. The SISTEMA library for the M35 Series is available for download from www.rosscontrols.com, enabling safety engineers to directly import verified safety data into their ISO 13849-1 SISTEMA projects without manual data entry. Integration guides and Safe Air Entry System Application Notes are available to assist with system-level design of pneumatic energy isolation circuits that incorporate the M35.

For direct application support, contact ROSS Controls at 1-800-GET-ROSS or visit www.rosscontrols.com to connect with a regional sales engineer or authorized distributor. ROSS Controls technical staff can assist with valve selection, port size and Cv optimization, monitoring circuit design, safety system integration, and certification documentation review. International customers are supported through ROSS Controls global distributor network, with technical resources available in multiple languages.

Download M35 Series 3D Interactive Product Demonstration PDF

What You Will Find in This Document

• Full 3D interactive model of the M35 Series valve in both Soft-Start and standard configurations
• Interactive toggle between "Valve with Soft-Start" and "Valve without Soft-Start" models
• 360-degree rotation, zoom, and pan navigation for complete external inspection
• Clearly visible port locations, M12 connector positions, solenoid housings, and silencer modules
• Physical size comparison between the two valve configurations, including the EEZ-ON module addition
• LED indicator locations and solenoid coil orientation for installation planning
• Built-in silencer module and valve body construction details
• Reference information for ROSS Controls technical support and product documentation resources

Who Should Download This Document

• Machine safety engineers responsible for designing Category 4 PL e pneumatic energy control circuits
• OEM machine builders specifying safe exhaust valves for new equipment designs
• Plant maintenance engineers evaluating replacement components for existing ROSS M35 installations
• Procurement and sourcing professionals reviewing pneumatic safety component specifications
• Automation and controls engineers integrating safe exhaust functions with safety PLCs and relay modules
• Risk assessors and CE marking consultants documenting machine safety measures for European market compliance
• Sales engineers and technical representatives presenting ROSS Controls products to end customers
• Training and onboarding personnel familiarizing new staff with pneumatic safety valve components

Related ROSS Controls Products and Documentation

• ROSS L-O-X Lockout Valve — Manual pneumatic lockout valve designed to complement the M35 in Safe Air Entry System Assemblies, providing a visible, padlockable point of pneumatic energy isolation for OSHA lockout/tagout compliance.
• ROSS Safe Air Entry System Assemblies — Pre-engineered assemblies combining the M35 double valve with the L-O-X lockout valve in a validated, certifiable pneumatic energy isolation package. Reduces system design time and supports audit documentation.
• ROSS M10 Series Double Valve — Alternative safe exhaust double valve platform for applications with different flow, pressure, or port size requirements. Available in multiple configurations with similar Category 4 PL e safety ratings.
• ROSS SISTEMA Library Files — Pre-formatted SISTEMA project files containing verified safety data (B10D, PFHD, MTTFD, DC) for ROSS safety products including the M35, enabling rapid ISO 13849-1 safety calculation completion.
• M35 Series Product Catalog — Comprehensive catalog document covering complete M35 ordering information, dimensional drawings, performance curves, wiring diagrams, installation instructions, and spare parts information.
• M35 Series Installation and Maintenance Manual — Step-by-step installation, commissioning, periodic testing, and maintenance procedures for the M35 valve, including recommended monitoring circuit configurations and fault response procedures.

Frequently Asked Questions

Q: What is the M35 3D PDF?

A: The M35 3D PDF is an interactive three-dimensional product demonstration document created by 3D Sales Technologies GmbH in collaboration with ROSS Controls. It presents the M35 Series 3/2 Safe Exhaust Control Reliable Double Valve in a fully navigable 3D model within a standard PDF file, viewable in Adobe Acrobat Reader DC. The document features two interactive valve configurations — with and without the optional EEZ-ON Soft-Start module — that users can select and compare within the same viewing session.

Q: What is the safe exhaust function?

A: Safe exhaust is the ability of a valve to not only stop the supply of compressed air to a downstream zone but also to actively exhaust all residual pneumatic pressure energy from that zone in response to a safety system shut-off command. The M35 achieves safe exhaust through its 3/2 normally closed dual poppet design: when de-energized, the valve blocks the supply port and opens the exhaust port, rapidly venting downstream pressure. This eliminates stored pneumatic energy that could otherwise cause unexpected actuator movement during maintenance access.

Q: What does the EEZ-ON Soft-Start module do?

A: The EEZ-ON Soft-Start module controls the rate at which pressure is restored to the downstream pneumatic circuit after a safe exhaust event. Rather than allowing full supply pressure to immediately pressurize the downstream system — which could cause sudden, high-speed actuator movement — the EEZ-ON module gradually increases outlet pressure until it reaches approximately 50% of the inlet supply pressure, then opens fully for unrestricted flow. This controlled re-pressurization prevents abrupt actuator strokes during system restart, protecting both personnel in the area and any product or tooling in the machine.

Q: What safety rating does the M35 achieve?

A: The M35 Series achieves Category 4, Performance Level e (PL e) per ISO 13849-1:2015 and Safety Integrity Level 3 (SIL 3) per IEC 62061:2005. These are the highest achievable ratings under their respective standards and reflect the M35's redundant dual valve element design, high diagnostic coverage from the dual pressure sensor monitoring system, and documented long-term reliability data (B10D of 25,000,000 cycles, PFHD of 7.71 × 10⁻⁹, MTTFD of 301.9 years).

Q: What is the operating pressure range?

A: The M35 Series operates across a supply pressure range of 30 to 150 psig (2 to 10 bar). This range covers the vast majority of industrial compressed air system operating pressures worldwide. The valve is available with 1/2 inch or 3/4 inch NPT or G threaded port connections to suit different flow volume requirements within this pressure range.

Q: How are the pressure sensors used for monitoring?

A: Each M35 valve incorporates two PNP solid state pressure sensors — one associated with each of the two independent valve elements. These sensors connect to the customer-supplied safety monitoring equipment via the 5-pin M12 connectors on the valve body. The safety system reads the state of both pressure sensors simultaneously on each machine cycle to verify that both valve elements are in the commanded position and that no discrepancy (indicative of a fault in one element) exists between the two channels. This dynamic, cyclical external monitoring approach is what enables the M35 to maintain its Category 4 PL e classification over its service life, provided monitoring is performed at least once per month.

Q: Can the M35 be part of a Safe Air Entry System?

A: Yes. ROSS Controls offers Safe Air Entry System Assemblies that integrate the M35 double valve with the ROSS L-O-X lockout valve into a complete, pre-validated pneumatic energy isolation package. The L-O-X provides a manually operated, visible, padlockable point of pneumatic isolation for OSHA lockout/tagout compliance, while the M35 provides the safety-rated automatic safe exhaust function. Together, they form a comprehensive system that addresses both the automated safety circuit requirements of ISO 13849-1 and the administrative energy control requirements of OSHA 29 CFR 1910.147.

Q: What is the difference between models with and without Soft-Start?

A: The primary functional difference is that the model with the EEZ-ON Soft-Start module provides controlled, gradual re-pressurization of the downstream circuit — rising slowly to approximately 50% of inlet pressure before opening fully — while the model without Soft-Start re-pressurizes the downstream circuit at the full rate permitted by the valve's flow capacity. The Soft-Start model also weighs more (6.5 lb / 2.9 kg versus 4.2 lb / 1.9 kg) and has a slightly lower Cv in the supply direction (4.1 vs 4.3). The exhaust flow capacity (Cv 7.6 / 7,400 Nl/min) is identical for both models. Both models achieve the same Category 4 PL e and SIL 3 safety ratings. The 3D interactive PDF allows users to visually compare the two configurations to assess fit within their machine design.