CAMLogic Overpressure Indicator MN21T Series

Introduction – CAMLogic Overpressure Indicator MN21T Series

The CAMLogic Overpressure Indicator MN21T Series ensures safe and efficient pressure control in silos and tanks by providing a reliable mechanical signal when preset pressure limits are reached. Operating without any external power supply, the MN21T uses a sensitive diaphragm that instantly reacts to pressure variations, activating a microswitch output for system monitoring or alarm activation. This makes it ideal for applications involving both liquids and bulk solids, where maintaining system integrity and safety is critical.

Constructed from die-cast aluminum with a stainless steel and EPDM membrane, the MN21T offers excellent durability and resistance against industrial environments containing dust, powders, and airborne particles. It delivers stable performance even in ATEX and IECEx certified hazardous zones (20/21/22), where explosive dust atmospheres may be present.

Engineered for quick and flexible installation, the device can be mounted in any orientation—vertically, horizontally, or at an angle—using its flanged connection options. With an IP65 ingress protection rating and adjustable sensitivity between 10–80 mbar (standard) or 200–1000 mbar (high-pressure version MN21TF), the MN21T ensures dependable performance in both light and heavy-duty industrial processes.

The MN21T Series is trusted by engineers and operators across various industries, including bulk material handling, food processing, and chemical manufacturing. Distributed in the UAE and MENA region by Dubai Sensor, it represents a cost-effective and maintenance-light solution for mechanical overpressure monitoring.

Key Features & Benefits

• Mechanical operation – No external power supply required.
  
  
• Instant response to pressure variation via sensitive diaphragm and microswitch.
  
  
• Two measurement ranges: 10–80 mbar (MN21T) and 200–1000 mbar (MN21TF).
  
  
• Flexible mounting – Vertical, horizontal, or angled positions.
  
  
• Robust housing – Die-cast aluminum body with EPDM/stainless-steel membrane.
  
  
• High reliability – Over 5 million mechanical cycles.
  
  
• Explosion-protected design – Certified for Zones 20/21 (standard) and 22 (optional).
  
  
• Ingress protection IP65 – Resistant to dust and water jets.
  
  
• Optional LED lamp for visual alarm indication.
  
  
• Easy maintenance – Membrane replacement only every 72 months.
  
  
• Complies with RoHS, EMC, and Food Contact EU standards.
  
  

Technical Specifications – CAMLogic Overpressure Indicator MN21T Series

Standards & Certifications

• ATEX Directive 2014/34/EU:
  
  
• II 1/2D Ex ta/tb IIIC T85°C IP65 Da/Db (Zones 20/21)
  
  
• II 3D Ex tc IIIB T85°C IP65 Dc (Zone 22 for A/L models)
  
  
• IECEx Certification: Ex ta/tb IIIC T85°C Da/Db
  
  
• EMC Directive 2014/30/EU – Electromagnetic compatibility
  
  
• Low Voltage Directive 2014/35/EU – Electrical safety
  
  
• RoHS Directive 2011/65/EU – Restriction of hazardous substances
  
  
• EC 1935/2004 – Food contact compliance
  
  
• EN 60079-14 / -17 / -19 – Installation, maintenance, and repair standards for hazardous areas
  
  
• Ingress Protection: IP65 (dust-tight and water-jet resistant)
  
  

Applications & Industries

Primary Applications

• Overpressure indication and protection in silos, storage tanks, and containers.
  
  
• Monitoring of pneumatic conveying or dust filtration systems.
  
  
• Safety signaling in bulk material and powder handling processes.
  
  

Target Industries

• Bulk material and grain handling
  
  
• Cement and construction materials
  
  
• Food and beverage manufacturing
  
  
• Chemical and pharmaceutical industries
  
  
• Energy and biomass plants
  
  

Widely used across industrial facilities in the UAE and MENA region, the MN21T Series is known for its reliability in harsh process conditions.

Installation, Commissioning & Maintenance

• The indicator can be mounted in any position on the silo or container wall using a matching counterflange.
  
  
• Ensure proper earthing connection (Class I, PE connected) before wiring.
  
  
• Seal cable entries with IP65-rated glands suitable for the working temperature.
  
  
• For hazardous area installation, follow IEC 60079-14 and ATEX zone guidelines.
  
  
• Avoid electrostatic buildup—do not dry rub plastic components.
  
  
• Periodically inspect sealing gaskets and replace the EPDM membrane every 72 months.
  
  
• Optional M12 connector available for fast, tool-free wiring connection.
  
  

Why Choose CAMLogic Overpressure Indicator MN21T Series

The CAMLogic MN21T Series combines mechanical simplicity with exceptional reliability. Its maintenance-free operation, rugged aluminum construction, and high sensitivity make it a dependable safety component in critical industrial systems. Designed for both standard and high-pressure ranges, it adapts easily to diverse application requirements without needing recalibration or external power.

For facilities seeking a durable, ATEX-certified, and cost-effective overpressure monitoring solution, the MN21T Series stands out for its longevity, accuracy, and European-built quality.

Ordering Guide

1. Select Model:
   
   
• MN21T → Standard sensitivity (10–80 mbar)
  
  
• MN21TF → High-pressure version (200–1000 mbar)
  
  
2. Choose Options (if required):
   
   
• A → Flush-mount screws
  
  
• F → Small flange version
  
  
• L → LED signal lamp (24V, 48V, 115V, or 230V AC/DC)
  
  
3. Specify Cable Entry Thread: M20×1.5, G ½, or ½ NPT
   
   
4. Confirm Certification Zone: ATEX Zone 20/21 or Zone 22 (L and A models)
   
   
5. Provide mounting and environment details for best configuration.
   
   

For procurement or technical assistance, contact Dubai Sensor, the official regional distributor of CAMLogic Overpressure Indicator MN21T Series.

CAMLogic Overpressure Indicator MN21T Series

Q1: What is the main function of the CAMLogic MN21T Series?
The MN21T Series acts as a mechanical overpressure indicator that prevents excessive pressure buildup in silos, tanks, or similar containers. It uses a diaphragm mechanism that triggers an internal microswitch to provide a signal when pressure exceeds the preset limit.

Q2: Does the MN21T require an external power supply?
No. The MN21T operates mechanically and does not require any external power. Only the optional LED lamp version (MN21T-L) needs a low electrical input (0.05 W).

Q3: What pressure ranges does the MN21T Series cover?
Two versions are available:

• MN21T: 10–80 mbar (standard sensitivity)
  
  
• MN21TF: 200–1000 mbar (high-pressure version)
  
  

Q4: Is the MN21T suitable for use in explosive dust environments?
Yes. The MN21T is ATEX and IECEx certified for Zones 20/21, and the A/L variants are approved for Zone 22 applications, ensuring safe use in explosive dust or powder atmospheres.

Q5: How often does the membrane need replacement?
The EPDM membrane should be replaced every 72 months (6 years) as part of preventive maintenance.

Q6: What materials are used for construction?
The housing is made from die-cast aluminum (powder coated), and the membrane is EPDM combined with stainless steel AISI 316, providing long-term resistance against corrosion and mechanical wear.

Q7: How should the device be installed?
The MN21T can be mounted in any position (vertical, horizontal, or angled) using a compatible counterflange. Ensure proper earthing, sealing, and compliance with IEC 60079-14 standards for hazardous areas.

Q8: What type of signal output does it provide?
It provides an SPDT potential-free contact output, rated at 2 A @ 250 VAC or 0.02 A @ 24 VDC, suitable for alarm or control signal integration.

Q9: Can I adjust the pressure sensitivity?
Yes. The MN21T features an adjustable spring preload nut, allowing fine-tuning of activation pressure between the minimum and maximum range.

Q10: Is it certified for food industry use?
Yes. The MN21T complies with EC 1935/2004, making it suitable for applications involving food-contact materials.

Q11: What is the ingress protection level?
The MN21T Series has an IP65 rating, ensuring dust-tight protection and resistance to water jets, suitable for both indoor and outdoor installations.

Q12: Where can I purchase the MN21T Series?
The MN21T Series is available through Dubai Sensor, the authorized distributor of CAMLogic products in the UAE and MENA region.