M DM2® Series C Double Valve with Integrated Soft Start – Installation Instructions (Discontinued)
Overview
The ROSS Controls® M DM2® Series C is a control-reliable double valve with integrated soft start function, designed for Category 4 safety applications except press clutch/brake use. The M DM2® Series C is base-mounted with three solenoids: two main solenoids for primary valve control, and one reset solenoid for manual reset after lockout. The integrated soft start function provides controlled gradual pressurization of downstream pneumatic systems, reducing actuator shock loading and preventing sudden uncontrolled machine motion on system restart.
Dynamic monitoring is performed cyclically during each actuation and de-actuation movement. The monitoring function has memory and requires an overt reset action after lockout. The M DM2® Series C is certified to Category 4, Performance Level e per ISO 13849-1, with functional safety data: B10D = 20,000,000; PFHD = 7.71×10⁻⁹; MTTFD = 301.9 years (at nop = 662,400 cycles/year). Certifications: CE, BG, CSA/UL, and TSSA.
Note: M DM2® Series C valves are discontinued products. Contact ROSS Controls at 1-800-GET-ROSS or visit www.rosscontrols.com for replacement product guidance.
Key Features
Integrated Soft Start Function
The M DM2® Series C integrates a soft start valve controlling the rate of pressurization when the valve actuates. Rather than instantaneously supplying full system pressure, the soft start function gradually increases downstream pressure, protecting cylinders and actuators from shock loading. This is especially valuable in applications with large actuator volumes or where controlled pressurization is required for safety during system restart.
Category 4, PL e Functional Safety with B10D 20 Million
The M DM2® Series C achieves Category 4, Performance Level e per ISO 13849-1. Functional safety data: B10D = 20,000,000 cycles; PFHD = 7.71×10⁻⁹; MTTFD = 301.9 years. Certified by BG and carrying CE, CSA/UL, and TSSA certifications for appropriately tested valves. Vibration/impact resistance tested per BS EN 60068-2-27.
IP65 Enclosure with M12 Connectors
The pilot solenoid enclosure meets IP65 per IEC 60529. Solenoid and status indicator connections use M12, 5-pin male receptacles (A-coded). The IP65 rating makes the M DM2® Series C suitable for washdown and dusty industrial environments.
Technical Specifications
The following specifications are drawn from the official ROSS Controls M DM2® Series C Installation Instructions (Doc ID 79):
- Construction: Dual Poppet
- Mounting Type: Base mounted
- Pilot Solenoids: 3 (primary a, primary b, reset c) per VDE 0580; rated for continuous duty
- Enclosure Rating: IP65 per IEC 60529
- Standard Voltages: 24 volts DC
- Power Consumption per solenoid: 1.2 watts on DC
- Solenoid & Status Indicator Connection: M12, 5-pin Male Receptacle, A-Coded
- Ambient Temperature: 15° to 122°F (-10° to 50°C)
- Media Temperature: 40° to 175°F (4° to 80°C)
- Flow Media: Filtered; mineral oils per DIN 51519, viscosity classes 32-46; 5-micron recommended
- Inlet Pressure: 30 to 150 psig (2 to 10.3 bar)
- Pressure Switch Rating: 5 amps at 30 volts DC
- Monitoring: Dynamic, cyclic, internal; memory function requires overt reset after lockout
- Mounting Orientation: Vertical with pilot solenoids on top
- Safety Data: Category 4 PL e; B10D = 20,000,000; PFHD = 7.71×10-9; MTTFD = 301.9 years
- Certifications: CE, BG, CSA/UL, TSSA
Applications
Controlled Pressurization for Machine Safety Restart
The integrated soft start makes the M DM2® Series C especially suitable for applications where pneumatic systems are regularly de-pressurized and re-pressurized during safety stops and machine restarts. By combining the double valve and soft start functions in a single base-mounted unit, it reduces component count and simplifies the safety circuit design.
Category 4 Applications with Audit Trail Requirements
The memory-with-reset function supports applications where regulatory requirements mandate that all safety circuit lockouts be recorded and cleared by authorized personnel. The overt reset requirement combined with the M12 status indicator connection enables integration with production monitoring and safety management systems.
Safety and Compliance Standards
The M DM2® Series C is designed for Category 4 applications per ISO 13849-1. It is expressly not for press clutch/brake applications. Before operating the M DM2® Series C, complete the test procedure upon installation and after any maintenance. Failure to do so could result in personal injury or equipment damage. Per ROSS safety notes, L-O-X® valves are defined as energy isolation devices, not emergency stop devices.
Installation and Setup Guide
Mounting Orientation and Connections
The M DM2® Series C must be mounted vertically with pilot solenoids on top. Connect the three M12, 5-pin A-coded connectors for primary solenoids (a and b) and the reset solenoid (c). Connect the status indicator output to the machine control system. Ensure supply inlet pressure is 30 to 150 psig (2 to 10.3 bar).
Minimum Inlet Pressure Considerations
Under conditions of maximum restriction of the adjustable flow control or very large downstream system volumes, the minimum inlet pressure may need to be set up to 60 psig (4 bar) to prevent nuisance valve faults. Ensure the supply provides adequate flow volume on demand, not just adequate static pressure.
Reset Procedure
To reset after lockout: ensure supply pressure present; de-energize both main pilot solenoids; then momentarily energize the reset solenoid. After reset, verify no pressure at outlet port and no audible exhaust flow before re-energizing main solenoids. Always follow the full test procedure after maintenance before returning to service.
Why Choose ROSS Controls
ROSS Controls has delivered control-reliable pneumatic safety solutions for over 100 years. The M DM2® Series C integrates safety valve and soft start functions in a single base-mounted unit. For current replacement products, contact ROSS at 1-800-GET-ROSS or visit www.rosscontrols.com.
Download This Document
The official ROSS Controls M DM2® Series C Double Valve with Soft Start Installation Instructions (Doc ID 79) can be downloaded from the ROSS Controls document library.
PDF Download URL: https://ross-admin-global-us-east.s3.amazonaws.com/production/uploads/document_language_file/file/79/ROSS_Modular_MDM_Series_C_with_Soft_Start_SS305.pdf
Related Products and Resources
- DM2® Series E Installation Instructions – Double valve with memory, no soft start (Doc ID 171)
- DM Series E Operating Instructions – Combined DM1/DM2® operating manual (Doc ID 383)
- MCSE Series – Current safe exhaust control-reliable double valves
- EEZ-ON® Series – Soft-start/dump valve for controlled pressurization
- ROSS Safety Products – www.rosscontrols.com
Frequently Asked Questions
Q: What is the integrated soft start function on the M DM2® Series C?
A: The integrated soft start function gradually increases downstream pressure when the valve actuates, rather than instantaneously supplying full system pressure. This protects actuators from shock loading and prevents uncontrolled fast motion during initial pressurization.
Q: What safety certification level does the M DM2® Series C achieve?
A: The M DM2® Series C is certified to Category 4, Performance Level e per ISO 13849-1. Functional safety data: B10D = 20,000,000 cycles; PFHD = 7.71×10⁻⁹; MTTFD = 301.9 years.
Q: What is the required mounting orientation for the M DM2® Series C?
A: The M DM2® Series C must be mounted vertically with pilot solenoids on top. Incorrect orientation may affect valve performance and monitoring reliability.
Q: What connector type is used for the M DM2® Series C solenoids?
A: Solenoid and status indicator connections use M12, 5-pin Male Receptacle, A-Coded connectors. This standard industrial connector type supports reliable IP65-rated connections.
Q: Why might the minimum inlet pressure need to be higher than 30 psig?
A: Under certain conditions – maximum flow control restriction or very large downstream volume – the minimum inlet pressure may need to be up to 60 psig (4 bar) to prevent nuisance valve faults.
Q: Is the M DM2® Series C suitable for press clutch/brake applications?
A: No. The M DM2® Series C is expressly not for press clutch/brake applications. ROSS produces the DM2® Series D specifically for press clutch/brake use.
Q: Is the M DM2® Series C still available?
A: The M DM2® Series C is a discontinued product. Contact ROSS Controls at 1-800-GET-ROSS or www.rosscontrols.com for current replacement product recommendations.
Q: What certifications does the M DM2® Series C carry?
A: Certifications include CE (for applicable directives), BG, CSA/UL, and TSSA for appropriately tested valves. Vibration and impact resistance tested per BS EN 60068-2-27.