UWT Signal Light Improves Process Safety in Hazardous Area Silo Monitoring

Phil Black - PII Editor 22 minutes ago

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nivoled rn3 light green_ — NivoLED® status indication for easy integration into existing sensors and plant components

Rotonivo® rotary paddle switches combined with the NivoLED® status light improve visibility, process safety and response times in the wood processing industry

Effective silo level monitoring plays a vital role in maintaining safe, efficient and reliable operations throughout the wood processing industry. Facilities that process timber generate significant volumes of wood shavings and wood chips, which must be handled safely before being reused or disposed of. In many manufacturing plants, these by-products are not treated as waste. Instead, they are used as a valuable renewable fuel source within on-site biomass power plants, helping to generate heat and electricity while reducing dependence on fossil fuels.

To ensure these biomass operations continue to run efficiently, reliable point level monitoring is essential. Accurate level detection helps prevent overfilling, ensures continuous material flow and supports safe operation in hazardous dust environments. By combining proven Rotonivo® rotary paddle level switches with the NivoLED® signal light, UWT has demonstrated how a straightforward retrofit can significantly improve process safety, maintenance efficiency and operator response times.

Reliable Monitoring of Wood Shavings in Biomass Power Plants

At a major European manufacturer of wood-based materials, the wood residues produced during manufacturing are utilised within an on-site biomass power plant. Before being transported for combustion and energy generation, the wood shavings and chips are temporarily stored in several storage silos.

Level monitoring across the entire facility is managed centrally through an advanced plant control system. Around 300 measurement points are integrated into the central visualisation platform, allowing operators to monitor storage levels and process conditions throughout the site.

For point level detection within the silos, UWT Rotonivo® RN 6003 and RN 6004 rotary paddle level switches had already been installed. These sensors have provided reliable performance for many years and form an important part of the site’s bulk solids handling system.

The Challenge: Elevated Temperatures and Rapid Status Recognition

The close proximity of the biomass power plant creates demanding operating conditions within the silo installation. Radiant heat generated by the combustion process results in elevated process temperatures that equipment must withstand while continuing to deliver accurate and dependable measurements.

Alongside these environmental challenges, plant operators also needed to identify equipment status more quickly to improve maintenance efficiency and minimise unplanned downtime.

Although the facility already benefitted from a comprehensive central process visualisation system, operators recognised the value of an additional local indication directly at each silo. The objective was to enable maintenance personnel to identify switching states immediately at the measurement point without first consulting the central control system, reducing delays during routine inspections and fault finding.

Robust Rotary Paddle Level Switches for Demanding Bulk Solids Applications

Rotonivo® rotary paddle level switches have been successfully used throughout the installation for point level monitoring over many years. Designed specifically for demanding bulk solids applications, the sensors provide reliable full, demand and empty level detection in storage silos and process vessels across a wide range of industries.

The Rotonivo® RN 6003 is engineered to withstand process temperatures of up to +250 °C and process pressures of up to 10 bar, making it suitable for challenging industrial applications.

For even more demanding operating environments, the Rotonivo® RN 6004 is capable of handling process temperatures of up to +600 °C while maintaining dependable performance under extreme conditions.

Both devices feature robust housings designed for installation within hazardous areas and carry SIL2 certification, supporting functional safety requirements in industrial process applications.

Large terminal compartments simplify installation and wiring while making it straightforward to retrofit additional accessories such as the NivoLED® signal light. The rotary paddle switches also offer excellent resistance to mechanical stress, ensuring long service life even in harsh operating environments.

nivoled vn4 light red — NivoLED® status indication for easy integration into existing sensors and plant components

Solution: Retrofitting NivoLED® Signal Lights

To improve local visibility of equipment status, a pilot installation was carried out on one silo already fitted with Rotonivo® point level switches. The existing installation was enhanced by adding the NivoLED® NL 9000 signal light.

The LED signal device displays the current switching status directly at the measuring point, providing immediate visual confirmation for operators and maintenance engineers working around the silo.

Its highly visible 360° illumination and high-intensity dual-colour LED indication in red and green ensure switching states remain clearly visible, even from considerable distances or in poor lighting conditions commonly found within industrial processing facilities.

During the evaluation period, the advantages of local visual indication quickly became evident. Operators were able to identify defined limit levels much faster while maintenance and servicing activities became more efficient because equipment status could be confirmed immediately on site.

These improvements shortened response times and helped reduce the risk of unnecessary downtime, supporting more efficient day-to-day plant operation.

Following the success of the initial installation, the solution was expanded across the site. A further 18 NivoLED® signal lights were subsequently installed at additional measuring points throughout the facility.

Customer Benefits: Improved Visibility, Faster Response Times and Greater Process Safety

The addition of local status indication delivers numerous operational advantages, particularly across large industrial sites with extensive silo storage systems and hundreds of measurement points.

Key benefits include:

Improved visibility directly at the silos
Faster recognition of switching states
Simplified maintenance and service activities
Reduced response times in the event of process deviations
Enhanced process safety during operation

By allowing operators to confirm equipment status immediately at the measuring point, local visual indication helps streamline workflows, reduce unnecessary travel around the site and minimise delays when responding to process events.

robust rn 6 rotary paddle witch_ — Robust RN 6 rotary paddle switch for demanding bulk solids applications with SIL2 certification and suitability for hazardous areas

Designed for Hazardous Areas Within the Wood Processing Industry

The NivoLED® signal light has been specifically developed for industrial applications operating within demanding environments.

Its highly visible 360° LED display provides clear indication of sensor and equipment status, allowing operators to assess plant conditions quickly and safely.

Thanks to its rugged construction together with ATEX and IECEx approvals, the signal light is particularly well suited to hazardous areas and dust-intensive environments commonly encountered throughout the wood processing, biomass, recycling and bulk solids industries.

The NivoLED® can be integrated directly onto sensors, control cabinets and process equipment, making it an ideal retrofit solution for existing installations where improved local status indication is required without extensive modifications.

A Small Upgrade with Significant Operational Benefits

This application demonstrates how relatively small enhancements to existing level measurement systems can deliver substantial improvements in everyday plant operation.

For industrial facilities managing hundreds of measurement points across complex processing operations, local status visualisation provides greater transparency, faster maintenance response and improved operational awareness.

By combining proven Rotonivo® rotary paddle level switches with the NivoLED® status light, operators can improve process safety, reduce maintenance delays and enhance the overall efficiency of hazardous area silo monitoring, helping ensure reliable operation of biomass power plants and wood processing facilities for years to come.

UWT GmbH
Westendstr.5
87488 Betzigau, Germany
info@uwtgroup.com
www.uwtgroup.com