CAMLogic MN21 Series Membrane Level Indicator

Introduction – CAMLogic MN21 Series Membrane Level Indicator

The CAMLogic MN21 Series Membrane Level Indicator is a robust, mechanical level detection solution designed to monitor bulk solid materials in silos, bins, and hoppers. Operating entirely without electrical power, it senses the level reached by powders or granules through pressure exerted on a durable membrane. The unit triggers an SPDT microswitch that provides a reliable on/off output signal for control systems.

Built with a die-cast aluminium housing and a stainless-steel reinforced EPDM membrane, the MN21 ensures longevity and resistance to wear from abrasive or dusty media. It offers adjustable sensitivity between 10 and 25 mbar, making it adaptable to a wide variety of materials with different densities.

The MN21 Series is engineered for universal installation—it can be mounted in vertical, horizontal, or oblique orientations—and features IP65 protection for harsh industrial environments. Its mechanical simplicity and rugged construction deliver an excellent cost-performance ratio, ideal for demanding industries across the UAE and wider MENA region.

Distributed by Dubai Sensor, the CAMLogic MN21 Series combines European engineering precision with dependable field performance, providing safe and accurate level indication even in potentially explosive atmospheres.

Key Features & Benefits

• No external power supply required – purely mechanical operation.
  
  
• Adjustable sensitivity range 10–25 mbar for different bulk densities.
  
  
• Die-cast aluminium housing and AISI 316 stainless steel + EPDM membrane for durability.
  
  
• IP65 protection against dust and water jets.
  
  
• Certified for ATEX and IECEx Zones 20, 21, and 22.
  
  
• Operates in wide temperature ranges: –40°C to +85°C (process) and –20°C to +70°C (ambient).
  
  
• Long mechanical life: >5 million cycles.
  
  
• Easy installation—no special tools required.
  
  
• Optional LED lamp for level indication (Zone 22 version).
  
  
• Available with standard flange (Ø180 mm) or compact flange (Ø154 mm) versions.
  
  

Technical Specifications – CAMLogic MN21 Series Membrane Level Indicator

Standards & Certifications

• ATEX: II 1/2 D Ex ta/tb IIIC T85°C IP65 Da/Db (Zones 20/21)
  
  
• IECEx: Ex ta/tb IIIC T85°C Da/Db (Zones 20/21)
  
  
• Optional Lamp Model (Zone 22): II 3 D Ex tc IIIB T85°C IP65 Dc
  
  
• Directives:
  
  
• 2014/34/EU (ATEX)
  
  
• 2014/30/EU (EMC)
  
  
• 2014/35/EU (LVD)
  
  
• 2011/65/EU (RoHS)
  
  
• 1935/2004/EC (Food Contact Compliance)
  
  
• Ingress Protection: IP65 (dust-tight, protected against water jets)
  
  
• Temperature Class: T85°C
  
  

Applications & Industries

• Bulk solid level monitoring in silos, hoppers, and storage bins.
  
  
• Suitable for powders, grains, granules, and other dry materials.
  
  
• Ideal for cement, plastics, chemicals, and food processing industries.
  
  
• Designed for explosive dust environments (Zones 20, 21, 22).
  
  
• Reliable for both indoor and outdoor industrial installations in automation systems.
  
  

Installation, Commissioning & Maintenance

• Can be mounted on silo or tank walls using matching counterflange.
  
  
• Install vertically, horizontally, or at an angle depending on application.
  
  
• Seal cable entries using certified IP65 cable glands suitable for the zone rating.
  
  
• Sensitivity adjustment via spring-loaded nut (10–25 mbar).
  
  
• Ensure both internal and external grounding points are properly connected.
  
  
• Replace EPDM membrane every 72 months or sooner if signs of wear appear.
  
  
• No routine maintenance required—visual inspection during servicing recommended.
  
  

Why Choose CAMLogic MN21 Series Membrane Level Indicator

The CAMLogic MN21 Series delivers reliable, maintenance-free level indication for bulk solid materials without the complexity of powered sensors. Its mechanical simplicity guarantees continuous operation even in challenging environments, while the robust aluminium and stainless-steel construction ensures long-term durability.

With its European manufacturing quality, ATEX and IECEx certifications, and versatile installation options, the MN21 is trusted across industries for its accuracy, safety, and outstanding value. For companies in the UAE and MENA region, Dubai Sensor provides local expertise and distribution support, ensuring rapid delivery and technical guidance.

Ordering Guide

1. Select Model:
   
   
• MN21 – Standard flange Ø180 mm
  
  
• MN21F – Small flange Ø154 mm
  
  
2. Choose Options:
   
   
• With or without LED lamp (Zone 22 version only)
  
  
• Cable entry thread: M20×1.5 / G ½ / ½ NPT
  
  
• Optional M12 connector for quick connection
  
  
3. Confirm Material Compatibility:
   
   
• EPDM + AISI 316 membrane suitable for general industrial and food-grade solids.
  
  
4. Contact Dubai Sensor:
   For verified CAMLogic MN21 units, Dubai Sensor is the official distributor for the UAE and regional markets, offering genuine parts and technical support.
   
   

CAMLogic MN21 Series Membrane Level Indicator

Q1. What is the operating principle of the CAMLogic MN21 Series?
The MN21 Series works through a pressure-sensitive membrane that detects contact with bulk materials such as powders or granules. When the material exerts pressure on the membrane, a microswitch (SPDT) inside the unit activates to send a signal indicating the level reached.

Q2. Does the MN21 require an external power supply?
No. The standard MN21 and MN21F operate mechanically and require no external power. Only models equipped with the optional LED lamp consume minimal power (about 0.05 W).

Q3. What types of materials can the MN21 detect?
It can detect virtually any bulk solid—powders, granules, grains, and dry particulate matter. The adjustable sensitivity range (10–25 mbar) allows adaptation to both light and heavy materials.

Q4. Where can the MN21 be installed?
The MN21 can be mounted vertically, horizontally, or at an angle on silo or hopper walls using its standard or small flange. It is suitable for both indoor and outdoor use under IP65 protection.

Q5. Is the MN21 suitable for explosive environments?
Yes. The MN21 is certified for ATEX and IECEx Zones 20 and 21, while the A and L models (with LED lamp) are suitable for Zone 22. These certifications ensure safe operation in areas containing explosive dust atmospheres.

Q6. How is sensitivity adjusted?
Sensitivity is set using a self-locking nut on the instrument. Turning it clockwise increases resistance (higher activation pressure), and counterclockwise reduces it. The standard activation is about 10 mbar and can be increased up to 25 mbar.

Q7. What maintenance does the MN21 require?
No regular maintenance is needed. However, it is recommended to visually inspect sealing gaskets when the cover is opened and to replace the EPDM membrane every 72 months or if signs of wear are observed.

Q8. What is the difference between MN21 and MN21F?
Both models operate identically. The MN21 uses a standard 180 mm flange, while the MN21F features a compact 154 mm flange for space-limited installations.

Q9. Can the MN21 be used for food-grade applications?
Yes. The MN21 complies with EU Regulation 1935/2004/EC for food contact materials, making it suitable for applications where hygiene and compliance are required.

Q10. Who supplies the MN21 in the UAE and MENA region?
Dubai Sensor is the official distributor of CAMLogic products in the UAE and surrounding regions, providing genuine MN21 Series units, technical assistance, and spare parts support.