Innovative Solutions
ICO3S Solenoid Poppet Valve – for Hazardous Area Applications
IMI Maxseal ICO3S Direct-Acting Solenoid Valve for Pneumatic Valve Automation
The IMI Maxseal ICO3S is a 3/2-way direct-acting poppet solenoid valve engineered for pneumatic valve automation systems requiring dependable switching under demanding operating conditions. Designed for spring-return actuator packages, it combines zero minimum operating pressure, compact NAMUR mounting, and robust construction for process isolation, emergency shutdown (ESD), and other safety-critical valve applications.
Available with threaded and NAMUR-mounted configurations, the ICO3S supports hazardous-area installations through certified Ex d and Ex ia options while offering low-power coil variants, corrosion-resistant 316L stainless steel construction, and functional safety certification for Safety Instrumented Functions where required.
Engineering Focus: This page reviews the ICO3S from an engineering perspective—including valve architecture, technical characteristics, installation options, application suitability, design considerations, and specification guidance—to support informed selection within pneumatic valve automation systems.
Why Engineers Specify the IMI Maxseal ICO3S
Selecting a solenoid valve for a pneumatic actuator package involves more than matching port size or voltage. Shutdown philosophy, actuator behaviour, available air pressure, installation layout, environmental conditions, and maintenance strategy all influence the final specification. The IMI Maxseal ICO3S is frequently selected where these engineering requirements demand predictable switching and practical integration into valve automation systems.
Direct-Acting Operation Without Minimum Pressure Requirements
The direct-acting poppet design operates independently of pilot pressure, allowing reliable switching from zero operating pressure. This makes the ICO3S suitable for actuator packages where pressure availability during a shutdown demand cannot always be assumed.
Compact Integration with Pneumatic Actuators
Direct NAMUR mounting reduces external tubing, minimizes potential leak paths, and simplifies installation on quarter-turn pneumatic actuators. The compact arrangement also improves accessibility during maintenance and replacement activities.
Designed for Demanding Process Environments
Corrosion-resistant construction, hazardous-area certified configurations, and multiple coil options allow the valve to be integrated into offshore facilities, refineries, chemical plants, LNG terminals, and other challenging operating environments.
Suitable for Safety-Critical Valve Automation
Where the solenoid valve forms part of a shutdown or safety-related actuator package, certified configurations and documented functional safety data support engineering evaluation as part of the complete Safety Instrumented Function.
Reduced Lifecycle Maintenance
Standardized mounting arrangements, accessible manual override options, and proven mechanical architecture simplify inspection, replacement, and long-term maintenance throughout the valve automation lifecycle.
Engineering Flexibility Across Project Requirements
Multiple enclosure types, electrical options, mounting configurations, and environmental certifications enable engineers to configure the ICO3S for new installations, package equipment, or brownfield modernization projects without changing the overall valve automation philosophy.
Engineering Specifications & Technical Characteristics
Selecting a solenoid valve requires more than checking a catalogue specification. Flow capacity, operating pressure, electrical characteristics, environmental conditions, and actuator compatibility should be evaluated together to ensure predictable valve automation performance throughout the equipment lifecycle.
Operating Pressure
Direct-acting operation eliminates the need for a minimum pilot pressure. Depending on the selected configuration, the ICO3S supports maximum operating pressure differentials up to 16 bar, allowing application across a wide range of pneumatic valve automation systems.
Flow Capacity (Cv / Kv)
The valve provides a nominal flow coefficient of Cv 0.6 (Kv 0.5). Engineering selection should confirm that actuator volume, tubing arrangement and required stroke time remain compatible with the available airflow.
Electrical Characteristics
Available with AC and DC coil options, including low-power configurations for continuously energized applications. Coil selection should consider supply voltage stability, duty cycle, cabinet thermal loading and power supply capacity.
Materials & Environmental Protection
316L stainless steel construction provides corrosion resistance for demanding industrial environments. Certified enclosure options are available for hazardous-area installations together with high ingress protection suitable for outdoor process applications.
Temperature & Sealing Options
Standard and low-temperature sealing materials allow the valve to be configured for different ambient conditions. Seal selection should reflect both operating temperature and media compatibility throughout the expected service life.
Installation & Certifications
The ICO3S is available with threaded and NAMUR-mounted configurations together with certified versions for hazardous-area applications and documented functional safety capability where required by project specifications.
Engineering Note: Product specifications should not be evaluated independently. Operating pressure, actuator volume, required stroke time, pneumatic circuit layout, coil duty cycle, and environmental conditions collectively determine whether the selected configuration will achieve the required valve automation performance.
Application & Integration Considerations
The IMI Maxseal ICO3S is specified as part of a complete valve automation package rather than as a standalone component. Its direct-acting architecture, compact footprint, and flexible mounting options allow integration into new installations, OEM packages, and modernization projects where dependable pneumatic switching is required.
Quarter-Turn Valve Automation Packages
The ICO3S is commonly integrated with spring-return pneumatic actuators operating ball, butterfly and plug valves. Direct NAMUR mounting simplifies installation while reducing external tubing and associated leak paths.
Emergency Shutdown (ESD) Valve Assemblies
Where rapid actuator venting and predictable switching are required, the ICO3S is frequently incorporated into ESD valve assemblies as part of the pneumatic control package supporting shutdown functions.
Hazardous-Area Installations
Certified configurations allow integration into process plants where hazardous-area compliance forms part of the project specification. Final configuration should always match the installation classification and environmental conditions.
OEM Valve Packages
Equipment manufacturers integrate the ICO3S into standardized actuator assemblies where compact dimensions, repeatable installation, and documented product performance simplify package engineering and factory testing.
Brownfield Replacement Projects
During maintenance or modernization projects, the ICO3S can often be introduced without redesigning the complete actuator package. Existing mounting arrangements, operating pressure, electrical supply and pneumatic layout should be verified before replacement.
Integrated Valve Automation Systems
The ICO3S is regularly combined with limit switches, position monitoring devices, air preparation units and other valve automation accessories to create complete actuator control assemblies tailored to project requirements.
Integration Note: Successful integration depends on the complete actuator package rather than the solenoid valve alone. Actuator volume, pneumatic tubing, air quality, control philosophy, and auxiliary accessories should all be reviewed during engineering to achieve the required operating performance.
Related Engineering Topic
The ICO3S is widely applied in shutdown valve assemblies ranging from conventional single-solenoid arrangements to more advanced redundant pneumatic architectures. The selection of the shutdown architecture is determined by the overall Safety Instrumented Function (SIF) design rather than the solenoid valve itself.
Explore Redundant Valve Manifold (RVM) Engineering →ICO3S Engineering Configuration Matrix
The ICO3S model code is built from a sequence of engineering selections. Each code position defines one configuration parameter, allowing existing model numbers to be decoded or new valve configurations to be specified before ordering.
ICO3S Model Code Structure
Y ① 1 ② ③ ④ ⑤ ⑥ ⑦ S
Y = Product Family | ①–⑦ = Engineering Configuration Positions | S = Standard Configuration
| Code Position | Engineering Parameter | Available Codes | Available Options |
|---|---|---|---|
| ① | ATEX Certification | 0 • 7 • X | Ex d • Ex mbe • Ex ia |
| ② | Port Configuration | 1 • 2 • 3 • 5 | 2/2 NC • 2/2 NO • 3/2 Universal • 5/2 Universal |
| ③ | Operation | A • B • C • P • S • T | Automatic • Auto Latching • Push Button Override • Push Button Reset • Jack Screw • Tamper Proof Reset |
| ④ | Port Size | A1 • E1 • A3 • E3 • NA • KF | 1/4 NPT • G1/4 • 1/2 NPT • G1/2 • NAMUR • Manifold |
| ⑤ | Voltage / Signal | B • C • D • E • G • J • M • T | 24 VDC • 50 VDC • 110 VDC • 125 VDC • 24 VAC • 110 VAC • 220/240 VAC • 120 VAC |
| ⑥ | Conduit / Signal Connection | 1 • 2 | M20 × 1.5 ISO(F) • 1/2 NPT(F) |
| ⑦ | Seat / Seal Material | H • V | Nitrile (-55°C to +90°C) • FKM (-20°C to +90°C) |
Engineering Note: The configuration matrix is intended for engineering review and model identification. It provides a structured method for decoding existing ICO3S part numbers or building a suitable configuration before consulting detailed product documentation.
Engineering Selection Guide – ICO3S Configuration Matrix
Each ICO3S model number is assembled from a series of engineering selections. The configuration diagram above illustrates the coding sequence, while the matrix below summarizes the available options for each code position. This enables engineers to decode existing model numbers or define a suitable configuration before reviewing detailed datasheets.
| Configuration Group | Available Codes | Engineering Options |
|---|---|---|
| ATEX Certification | 0 / 7 / X | Ex d, Ex mbe, Ex ia |
| Port Configuration | 1 / 2 / 3 / 5 | 2/2 NC, 2/2 NO, 3/2 Universal, 5/2 Universal |
| Operation | A, B, C, P, T, S | Automatic, Latching, Push Button, Manual Reset, Tamper Proof, Jack Screw |
| Port Size | A1, E1, A3, E3, NA, KF | 1/4 NPT, G1/4, 1/2 NPT, G1/2, NAMUR, Manifold |
| Voltage / Signal | B, C, D, E, G, J, M, T | 24 VDC, 50 VDC, 110 VDC, 125 VDC, 24 VAC, 110 VAC, 220/240 VAC, 120 VAC |
| Conduit Connection | 1 / 2 | M20 × 1.5 ISO(F), 1/2 NPT(F) |
| Seat / Seal Material | H / V | Nitrile, FKM |
Engineering Observation: Unlike the ICO4S platform, ICO3S configuration is typically driven by hazardous-area certification, actuator interface, and shutdown philosophy rather than high-flow or hydraulic operating requirements. For this reason, the ATEX classification and NAMUR mounting arrangement are often established before selecting voltage, conduit entry, or sealing materials.
Typical ICO3S Configuration Examples
The following examples represent two commonly specified ICO3S configurations for shutdown applications. Rather than listing every available option, these examples illustrate how complete model numbers are used in typical engineering specifications and procurement documents.
| Model Number | Typical Application | Engineering Highlights |
|---|---|---|
| YX13AA1H1BS | Typical NAMUR Emergency Shutdown Valve | 3/2 Universal • Automatic Operation • NAMUR Mounting • High Nitrile Seal • Standard Power Coil |
| Y013AA3H2BS-LP | Low-Power Shutdown Configuration for SIS Applications | 3/2 Universal • 1/2″ NPT Ports • High Nitrile Seal • Low-Power Coil (<2 W) • Reduced Power Consumption |
Engineering Note: The -LP (Low Power) suffix identifies configurations equipped with low-power solenoid coils requiring less than 2 W. These models are commonly specified for intrinsically safe circuits, battery-backed shutdown systems, remote installations, and applications where minimizing continuous power consumption and heat generation is important.
Engineering Discussions from the Field
The following discussions reflect practical engineering questions raised during project specification, package design, commissioning, and maintenance of pneumatic valve automation systems.
Why doesn’t a higher Cv always produce a faster actuator closing time?
Cv represents only one part of the pneumatic circuit. Actuator volume, tubing length, fittings, exhaust accessories, supply pressure, and downstream restrictions may become the controlling factors. Increasing valve flow capacity alone does not guarantee shorter stroke times.
When should a direct-acting valve such as the ICO3S be preferred over a pilot-operated design?
Direct-acting valves are often selected where reliable switching is required despite low or fluctuating supply pressure. The final decision should also consider actuator demand, available airflow, and overall package design.
Can reducing coil power improve system reliability?
In continuously energized applications, lower-power coils can reduce enclosure temperatures, cabinet heat dissipation, and power demand. However, the selected coil must still provide reliable operation across the specified voltage tolerance and ambient temperature range.
Can an existing ICO3S valve be replaced by matching the model code alone?
No. The model code is the starting point, but engineers should also verify operating pressure, hazardous-area approval, valve function, manual override type, electrical supply, conduit entry, seal material, and actuator interface before confirming interchangeability.
Why is the complete model code important when ordering a replacement ICO3S valve?
The complete model code defines the valve configuration, including hazardous-area certification, valve function, port connections, operating mode, electrical supply, conduit entry, and seal material. Ordering by description alone can result in an incompatible replacement.
Which engineering checks should be completed before replacing a suspected faulty solenoid valve?
Verify supply pressure, coil voltage under load, actuator movement, manual override position, exhaust restrictions, tubing integrity, and air quality before concluding that the valve itself is the source of the problem.
Need Help Selecting or Verifying an ICO3S Configuration?
Whether you are specifying a new shutdown valve or replacing an existing ICO3S, selecting the correct model involves more than matching the part number. Nordenflow reviews the complete valve automation package to verify configuration compatibility, identify potential risks, and recommend the most appropriate engineering solution before procurement.
Information That Helps Our Engineering Review
- Existing ICO3S model number or a clear photo of the valve nameplate (if available)
- Actuator manufacturer and model
- Required valve configuration (2/2, 3/2, NAMUR, Inline, etc.)
- Operating medium and available supply pressure
- Required closing/opening time or shutdown requirements
- Coil voltage and hazardous-area classification (ATEX / IECEx, if applicable)
- P&ID, hook-up drawing, or pneumatic schematic (optional but recommended)
Our Engineering Approach: Rather than recommending a valve based solely on its specification, we review the complete shutdown package—including actuator characteristics, pneumatic supply, hazardous-area requirements, mounting arrangement, and operating philosophy—to confirm configuration compatibility or recommend a more suitable alternative.
Need higher flow capacity, hydraulic operation, or support for larger actuator volumes? Explore the IMI Maxseal ICO4S Platform →