When it comes to monitoring air flows in potentially explosive atmospheres, the ATEX flow monitor is your first choice. We at SEIKOM Electronic offer you a comprehensive range of flow monitors with Safety Integrity Level (SIL) and explosion protection (ATEX/IECEx). In order to meet the high requirements for air monitoring in ATEX zones 2 and 1, we have developed the flow monitors ATEX NLSW®45-3 Ex and NLSW®75-A Ex developed. In combination with the F3.x Ex sensors, you are ideally equipped for safety in hazardous areas.

We also offer you the evaluation units NLSW®45-3 Ex SIL1 and NLSW®45-3 Ex SIL2 in connection with Sensor F3.x Ex SIL1 and Sensor F3.x Ex SIL2 with additional SIL1 or SIL2 classification, verified by exida.

Exemplary areas of application

Chemical plants

Monitoring of proper supply air

Painting systems

Monitoring of a constant overpressure in production areas

Sewage and wastewater treatment plants

Monitoring of air circulation in clarifiers

Available devices (product feed)

With evaluation unit and separate sensor

Sensor F3 Ex

From 303.70 Excl. VAT

The evaluation unit of these airflow monitors and sensors are certified in accordance with IEC 61508, which corresponds to performance level C or D in accordance with EN ISO 13849-1. Choose a measuring device with or without analog output (0-10 V, 4-20 mA) and relay output to suit your requirements for air flow monitoring in hazardous areas.

Important: The evaluation units are always installed outside the potentially explosive area. Zener barriers are always included in the scope of delivery of the evaluation unit. Hazardous area protect. Only the F3.x Ex sensors are installed in potentially explosive atmospheres. As the flow sensors are simple electrical equipment, their use is permitted in both ATEX zone 2 and zone 1.

Discover our selection of flow monitors for explosion protection and ATEX productsthat impress with the 100% "Made in Germany" label. We look forward to providing you with a customized offer for our ATEX flow monitors.

Your professionals: Flow monitors for air in ATEX areas

For 30 years, more than 10,000 satisfied customers have relied on the highest level of expertise in the field of innovative measurement and control technology. Our consistent efforts to ensure comprehensive quality assurance, which is confirmed by TÜV Nord, make a significant contribution to this. The majority of our appliances are TÜV type-tested and annual production monitoring is carried out by TÜV Nord. The fact that we are one of the leading suppliers in our field today is also due to the fact that we always keep up with the state of the art. Whether temperature measurements with temperature sensors, pressure measurements with Pressure transmittersMeasure air quality Heating, ventilation, air conditioning devices and much more, we from SEIKOM Electronic are your reliable partner when it comes to sophisticated products. One example of this is our ATEX flow monitors.

We also attach particular importance to comprehensive services. In this context, we take a lot of time for your personal consultation and accompany you throughout the entire life cycle of an ATEX flow monitor and co. from our range. It goes without saying that we are quick to answer questions and process orders.

ATEX airflow monitor

Why opt for airflow monitors in ATEX areas?

Flow monitors for air ATEX are essential for monitoring in potentially explosive atmospheres. They perform valuable work in controlling and measuring air flows in environments where there is a high risk of explosions. These include industries such as chemicals, mining, oil and gas or in plants that work with flammable gases, vapors or dusts. In these environments, it is crucial to closely monitor the air flows with an ATEX flow monitor in order to avoid potentially dangerous situations, intervene in good time and ensure safety.

The special feature of the ATEX flow monitor is that it has been developed and certified in accordance with the strict safety regulations. EX protected flow monitors must be designed in such a way that they cannot generate sparks or reach temperatures that could trigger an explosion. They must be robust and reliable in order to work precisely even under harsh conditions.

An ATEX flow monitor should therefore always be certified for use in EX areas, as we are, and comply with the applicable standards and regulations. To ensure constant performance and safety, regular inspection of the devices is also essential.

When selecting and configuring your ATEX flow monitors, we make sure that they are suitable for the specific properties of the respective EX area. This applies above all to the type of flammable gases and the ambient conditions. This makes the ATEX air flow monitor an important part of your integrated safety strategy.

Airflow monitoring

How does airflow monitoring work in EX areas?

Depending on the type of sensor used, ATEX flow monitors work according to a different principle. In calorimetric velocity or flow measurement, the flow rates of gas or liquid are measured as a function of the heat transfer within the medium to be measured. The basic principle of an ATEX calorimetric flow monitor is relatively simple: a heating element and at least one temperature sensor are positioned directly in the air flow. The heating element continuously emits heat to the surrounding medium. The amount of heat transferred and the resulting temperature change in the medium are recorded by the sensor.

As the heat transfer depends on the speed of the flow - fast-flowing gases dissipate more heat than slow-flowing gases - the sensor can transfer the temperature difference to the flow speed and draw conclusions about the flow rate of the medium.

Calorimetric flow meters are known for their accuracy and reliability and are therefore often used where precise flow measurements are required. They are also able to function in a variety of environments, including those with corrosive or contaminated flows, and require relatively little maintenance compared to other flow meters. Their versatility makes them a popular choice in areas such as chemical processing, HVAC systems, automotive, and water and wastewater treatment.

What are the advantages of ATEX flow monitors in explosion protection?

ATEX areas require special safety precautions, as even small sparks or excessively high temperatures can trigger an explosion. One of the main advantages of flow monitoring in ATEX areas is increased safety. By continuously monitoring all gas or air flows with an ATEX flow monitor, potentially dangerous conditions such as gas leaks or unusual flow patterns can be detected at an early stage. This enables you to intervene quickly and prevent serious accidents.

In addition, efficient monitoring of the air flows using ATEX flow monitors ensures optimized process control. In many industrial productions, the precise control of gas or air flows is crucial for product quality and efficiency. Precise measurements allow work processes to be better controlled and optimized. This in turn contributes to increased efficiency and cost savings.

Ultimately, with an ATEX flow monitor you meet the legal safety standards for your company.

In summary, flow monitoring systems for ATEX areas offer the following advantages:

  • Increased safety: early detection of hazardous conditions such as gas leaks
  • Optimized process control: precise control of air and gas flows to improve product quality and efficiency
  • Compliance with safety regulations: fulfillment of legal requirements and avoidance of penalties
  • Cost savings: Increased efficiency through optimized processes and avoidance of accidents and downtime
  • Risk minimization: reducing the risk of explosions and other safety-related incidents

What is the difference between zone 1 flow monitors and zone 2 flow monitors?

Although the flow monitors from SEIKOM Electronic can be used in both Zone 1 and Zone 2, the main differences between these zones lie in the frequency and duration of the occurrence of explosive atmospheres.

Zone 1

Zone 1 includes areas in which an explosive atmosphere consisting of a mixture of air and flammable gases, vapors or mists occasionally occurs under normal operating conditions. Flow monitors used in this zone are designed to function safely even under these more frequently occurring and potentially longer-lasting explosive conditions.

Zone 2

Zone 2 refers to areas in which an explosive atmosphere occurs only rarely and for a short time. Although the probability of an explosive event in Zone 2 is lower, it still requires the use of equipment that is protected against such rare but potentially dangerous situations.

The flow monitors from SEIKOM Electronic, which can be used in both zones, have no technical differences due to their zone affiliation. The main difference between the zones lies in the ambient characteristics and the probability of an explosive atmosphere occurring. The selection of a suitable ATEX flow monitor is therefore not based on technical differences between the devices, but on a precise assessment of the specific conditions and risks at the place of use.

What are the areas of application for ATEX flow monitors?

Certified ATEX flow monitors are used in various areas, all of which have in common that the atmosphere represents a potential explosion hazard.

These include:

Chemical industry

In systems where flammable chemicals, solvents and gases are used, precise monitoring of the air flow is necessary to prevent explosive mixtures.

Oil and gas industry

In refineries, drilling platforms and pipelines where flammable liquids and gases are processed, ATEX flow monitors are crucial for safety.

Pharmaceutical industry

In the production and processing of pharmaceuticals, where volatile substances are often handled, these ATEX flow monitors help to ensure safe working conditions.

Power plants

Especially in areas where coal is processed, monitoring the air flow is important to minimize the risk of dust explosions.


Underground mines, especially those that release flammable gases such as methane, require constant airflow monitoring to ensure worker safety.

Paint and varnish industry

The production and processing of paints and varnishes often involves highly flammable solvents, which requires precise monitoring of the air flow using an ATEX flow monitor.

This is what you can expect from our range of EX protected flow monitors

You install our evaluation unit and the Zener barriers included in the scope of delivery outside the area where there is a risk of explosion. Inside the area, you install the sensors, which are equipped with a 2.5 meter cable as standard. On request, this cable can be extended to a length of up to 30 meters.

The NLSW®45-3 Ex evaluation unit is specially designed for flow monitoring in ATEX areas. It is suitable for monitoring the air flow in the ATEX zones 1 and 2 and is optionally available with SIL1 or SIL2 certification. The intrinsically safe flow monitor has a switching output for switch cabinet installation and has been tested by TÜV NORD in accordance with DIN EN 61010-1: 2011-07. With a measuring range of 0.1 to 30 m/s, it is suitable for a wide range of applications, such as monitoring industrial processes.

The NLSW45-3 Ex SIL2 evaluation unit with SIL2 certification in accordance with IEC 62061 is available for safety-critical industrial applications. This version can be used in ATEX zones 1 and 2, covers a measuring range of 0.1 to 20 m/s and is suitable for media temperatures from 0 °C to 60 °C. It is used in areas such as electronics production, test benches, environmental systems and power plants. It is used in areas such as electronics production, test benches, environmental plants and power stations.

If you have any further questions about ATEX flow monitors or would like individual advice, please do not hesitate to contact us. In our Product categories you are guaranteed to find something for your needs when it comes to temperatures, flows, pressures, levels and much more. We are there for you by phone or e-mail.

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