Low/High Temperatures, DIN & M12 Connection [21 Series] 2/2, 3/2, & 4/2 Functions, 1/4" to 1-1/2" Port Sizes

Product Overview

The ROSS Controls is a family of inline poppet directional control valves within the proven 21 Series platform, purpose-built for pneumatic systems that demand reliable airflow control in extreme temperature environments ranging from -40F (-40C) to 300F (150C). Featuring DIN EN 175301-803 and M12 electrical connections, these TUV-certified (SIL 2) valves offer 2/2, 3/2, and 4/2 functions in port sizes from 1/4" to 1-1/2", with maximum flow capacity reaching Cv 33 (32,000 Nl/min).

The this series directional control valves regulate the direction, flow, and isolation of compressed air within pneumatic circuits. Available in both solenoid pilot controlled and pressure (pneumatic) controlled configurations, these valves leverage ROSS's signature poppet construction, a design that eliminates the sliding friction and wear mechanisms inherent in traditional spool-type valves.

The perpendicular poppet face seal geometry creates a high-flow path with positive shutoff, while the differential piston design delivers fast, consistent response times across millions of cycles. Fluorocarbon and Buna-N seal options extend the operational envelope to cover both low-temperature cold storage and high-temperature industrial process environments.

For design engineers specifying pneumatic components in demanding applications, the series provides a unique combination of extreme temperature tolerance, high flow capacity, SIL-rated safety performance, and quick-disconnect DIN/M12 electrical connections that simplify installation and maintenance in the field.

Key Engineering Features

• Perpendicular Poppet Face Seals - Creates high-flow capacity with near-zero leakage and positive sealing, eliminating the bypass losses common in spool valves.
• Differential Piston Design - Delivers fast and consistent response times throughout the life of the valve, critical for high-cycle automation applications.
• Overwhelming Shifting Forces - Provides no-stick operation even after extended idle periods or in contaminated environments, ensuring reliable actuation every cycle.
• High-Velocity Air Flow Across Poppet Seats - Enables self-cleaning action and strong dirt tolerance, reducing unplanned downtime in harsh industrial settings.
• Superior Internal Guidance System with Self-Compensating Seals - Automatically adjusts stroke length as seals wear, delivering extended service life without performance degradation.
• DIN EN 175301-803 and M12 Quick-Disconnect Connections - Simplifies installation and allows rapid coil replacement without hardwired connections, reducing maintenance time significantly.
• Non-Locking Manual Override - Standard on all solenoid-controlled models for commissioning, troubleshooting, and system verification without external tools.
• TUV SIL 2 Certification (SIL 3 in Redundant Configuration) - Enables integration into safety-related control architectures per IEC 62061 and ISO 13849, the highest safety integrity levels for pneumatic components.
• Downloadable CAD Models - Available for all variants to streamline machine design integration and reduce engineering lead time.

Technical Specifications

General Specifications

Temperature Ratings

The this series is specifically designed for operation outside standard temperature ranges. Seal material selection determines the applicable temperature envelope.

Important: For media temperatures below 40F (4C), compressed air must be free of water vapor to prevent ice formation inside the valve.

Electrical Data (Solenoid Pilot Valves)

All solenoids are rated for continuous duty with an IP65 enclosure rating.

Electrical Connection Options

Flow Performance Data

Flow performance data for 2/2 Solenoid Pilot controlled valves (select sizes shown).

Response Time Formula: Response Time (ms) = M + (F x V), where M is the minimum response constant, F is the fill/exhaust factor, and V is the downstream volume in cubic inches. M and F values are published per port size and function in the ROSS 21 Series catalog.

Certifications & Compliance

Typical Applications & Industries

Metals Processing and High-Temperature Manufacturing

• Steel furnaces, hot rolling mills, annealing lines, galvanizing, and continuous casting where ambient and media temperatures routinely exceed 180F. The Fluorocarbon seal option ensures reliable operation in sustained high-heat environments.
• Thermoforming and plastics manufacturing for controlling vacuum and pressure air in heated mold zones where standard seals would degrade.
• Glass manufacturing for directional air control near furnaces and forming stations operating at extreme temperatures.
• Foundry operations for controlling pneumatic cylinders and actuators in proximity to molten metal operations.

Cold Storage, Food and Beverage Processing

• Cold storage and refrigeration facilities operating pneumatic actuators in freezer environments down to -40F. Buna-N seals maintain flexibility and sealing integrity at cryogenic temperatures.
• Food and beverage processing including blast freezing, cryogenic packaging, and cold chain automation lines where standard valve seals become brittle and fail.

Automotive and Assembly Manufacturing

• Automotive body shop actuators, paint line controls, and assembly automation where reliable cycling and dirt tolerance reduce maintenance intervals.
• Assembly and test operations including leak testing, vacuum pick-and-place, and channel-select test fixtures requiring precise directional air control.

Packaging and General Industrial

• Vacuum packaging, case erecting, carton sealing, and palletizing systems benefiting from the high-flow, self-cleaning poppet design.
• Semiconductor and electronics manufacturing for clean air directional control in temperature-controlled process zones.
• Outdoor installations in arctic or cold-climate pipeline control and processing facilities where ambient temperatures drop below -40F.

Ordering and Model Number Configuration

The ROSS 21 Series uses a structured model number system. Below is a breakdown for a 2/2 solenoid pilot controlled valve.

Voltage codes: H = 12 VDC, W = 24 VDC, Z = 120 VAC/60 Hz, Y = 240 VAC/60 Hz.

Coil type codes for solenoid models: 1 = DIN Form A (standard), 2 = DIN Form B (standard), 3 = M12, 4 = 1/2" Conduit (standard), 5 = DIN Form B (low temp, Buna-N required), 6 = 1/2" Conduit (high temp, Fluorocarbon required).

For G (BSPP) threads, add "D" after the series prefix (e.g., D2171B2001W-1). Low-temperature solenoid options are available in 3/8 and 3/4 body sizes only.

Accessories

Electrical Connectors

ROSS offers a full range of prewired and standalone DIN EN 175301-803 connectors in Form A and Form B configurations, with options for cable grip or 1/2" NPT conduit entry. Lighted connector versions are available for 24 VDC, 120 VAC, and 230 VAC to provide visual solenoid-energized indication.

Exhaust Silencers

Aluminum exhaust silencers are available for port sizes 1/2", 1", and 1-1/2", rated to 290 psig (20 bar).

Warning: Exhaust silencers must have flow capacities at least as great as the exhaust capacities of the valves. Contaminated silencers can cause increased back pressure and affect valve operation.

Related Products & Accessories

• 21 Series Classic Low/High Temperature Valves - Standard 1/2" conduit connection variants of the 21 Series for extreme temperature applications. https://www.rosscontrols.com/en/series/231-low-high-temperatures-classic-21-series
• 27 Series Standard Temperature Valves - Standard temperature inline poppet valves with port sizes up to 2-1/2" for higher flow requirements. https://www.rosscontrols.com/en/series/230-standard-temperatures-classic-27-series
• Vacuum Low/High Temperature 21 Series (DIN/M12) - Vacuum-rated variant of the 21 Series with DIN and M12 connections for vacuum applications in extreme temperatures. https://www.rosscontrols.com/en/series/2760-vacuum-low-high-temperatures-din-m12-connection-21-series
• Electrical Connectors - DIN and M12 connectors, prewired assemblies, and lighted indicators for ROSS solenoid valves. https://www.rosscontrols.com/en/series/91-electrical-connectors
• Exhaust Silencers - Aluminum silencers rated to 290 psig for port sizes 1/2" through 1-1/2" to reduce exhaust noise. https://www.rosscontrols.com/en/series/90-silencers
• Lockout Valves (Energy Isolation) - L-O-X lockout valves for safe energy isolation during maintenance per OSHA lockout/tagout requirements. https://www.rosscontrols.com/en/series/1287-lockout-valves-15-series

Frequently Asked Questions (FAQ)

Q: What makes the ROSS different from the standard 21 Series?

A: The this series is the DIN and M12 connection variant of the 21 Series, specifically configured with quick-disconnect coils and extended temperature seal options (Fluorocarbon for high temp up to 300F; Buna-N for low temp down to -40F). The standard 21 Series valves with classic connections operate within a narrower temperature window of 0F to 122F.

Q: What is the maximum operating temperature?

A: The highest-rated configuration, a pressure-controlled valve with Fluorocarbon seals, supports ambient and media temperatures up to 300F (150C). For solenoid pilot models, maximum media temperature is 300F with an ambient limit of 180F.

Q: What is the minimum operating temperature?

A: With Buna-N seals, the low-temperature models operate down to -40F (-40C) for both ambient and media conditions. This makes them suitable for arctic environments and cold-storage applications.

Q: Can these valves be used in safety-critical (SIL-rated) applications?

A: Yes. The 21 Series is TUV Rheinland certified to SIL 2 (IEC 61508/61511) and PL c (EN ISO 13849-1) in singular application. In a redundant (1oo2) configuration, the valves achieve SIL 3 and PL e.

Q: What seal material should I select?

A: Choose Fluorocarbon for high-temperature applications (media up to 300F) and Buna-N for low-temperature applications (down to -40F). Note that the low-temperature DIN Form B coil (code 5) requires Buna-N seals, while the high-temperature conduit coil (code 6) requires Fluorocarbon seals.

Q: Are NPT and BSPP (G) thread options both available?

A: Yes. Standard models ship with NPT threads. To order with G (BSPP) threads, add "D" as a prefix to the model number (e.g., D2171B2001W-1).

Q: What pilot supply pressure is required?

A: For internal pilot supply, the inlet pressure must meet the minimum 30 psig operating threshold. For external pilot supply, the pilot pressure must be equal to or greater than inlet pressure and must meet the minimum operating pressure.

Q: Do these valves require lubrication?

A: The valve itself does not require air line lubrication. However, if optional adaptors (such as air index devices) are installed, lubrication may be necessary. When used, lubricant should be petroleum-based, ISO 32 viscosity or lighter, at approximately one drop per minute.

Q: What is the IP rating of the solenoid enclosure?

A: All solenoid pilot valves carry an IP65 enclosure rating, providing dust-tight protection and resistance to low-pressure water jets.

Q: Can the valve be converted from internal to external pilot supply in the field?

A: Yes. ROSS 21 Series valves can be field-converted from internal to external pilot supply by relocating the pipe plug between the external pilot port and the internal pilot passage. Contact ROSS for the updated model number to maintain proper documentation.

Q: Are 3D CAD models available for design integration?

A: Yes. Downloadable CAD models are available for all this series variants through the ROSS Controls website at rosscontrols.com.

Q: What is the expected lead time?

A: Standard manufacturing lead times for quantities of 10 or fewer units are typically 3 to 4 weeks, with shipping available throughout the United States.

Q: How do I calculate valve response time?

A: Use the formula: Response Time (ms) = M + (F x V), where M is the minimum response constant, F is the fill/exhaust factor, and V is the downstream volume in cubic inches. M and F values are published per port size and function in the ROSS 21 Series catalog.

Installation & Maintenance Guidelines

• Mount inline in any orientation; vertical mounting is preferred for optimal performance and condensate drainage.
• Supply filtered air (5-micron filtration recommended) to maximize valve life and prevent contaminants from interfering with poppet sealing.
• Do not restrict supply lines or exhaust ports, as this can reduce pressure below the 30 psig minimum and cause erratic operation.
• For external pilot supply configurations, pilot pressure must be equal to or greater than inlet pressure.
• Air must be free of water vapor at media temperatures below 40F (4C) to prevent ice formation inside the valve.
• Use only petroleum-based lubricants with an aniline point between 180F and 220F, ISO 32 viscosity or lighter. Avoid phosphate-type additives.
• Verify that exhaust silencers have flow capacities at least as great as the exhaust capacities of the valves. Contaminated silencers can cause increased back pressure.
• Ensure minimum pilot pressure of 30 psig for all valve functions. Pressures below this threshold may result in incomplete shifting.
• When installing in high-temperature environments (above 180F ambient for solenoid models), verify that the solenoid coil is rated for the application temperature and that Fluorocarbon seals are specified.
• For low-temperature installations below 0F, confirm that Buna-N seals are specified and that compressed air supply is dried to a dew point below the minimum operating temperature.

Warranty & Global Support

ROSS Controls provides a one-year warranty on all products, covering defects in material and workmanship from date of purchase.

Global technical support is available through ROSS offices in the USA (headquarters in Ferndale, Michigan), Canada, Brazil, Germany, France, United Kingdom, India, China, and Japan.

Contact ROSS Controls USA at +1-248-764-1800 or visit rosscontrols.com for product configuration, technical support, and distributor locator services.

For complete technical data, dimensional drawings, and valve configurator access, visit the ROSS Controls product page or contact ROSS Controls at (800) 438-7677.

Download Catalog: https://www.rosscontrols.com/en/documents/5341/Directional_Control_Valves_21_Series_ROSS-21_EN.pdf