JES Elektrotechnik Environmental Monitoring Sensors for Transport Applications
JES Elektrotechnik (JES) is a leading provider of environmental monitoring solutions for transport infrastructure applications.
Designed for a safe and reliable operation, our sensors are made from durable materials to achieve the highest return on investment for road operators.
Our product range includes tunnel sensors for monitoring air flow, air quality and lighting conditions; road weather stations, and gas warning systems for underground car parks.
Environmental monitoring sensors for road tunnels
Environmental conditions in tunnels are influenced by particles, emissions and fog, and need to be monitored to protect people from personal danger.
Accidents in tunnels, particularly fires, can have dramatic consequences and result in congestion, pollution and repair costs. People in the tunnel consistently need to be supplied with breathable air and sufficient visibility.
Over the last 30 years, tunnel sensors from JES have proven to be reliable and precise in more than 400 tunnels worldwide.
Early fire detection by visibility or smoke monitoring
Fire incidents in road tunnels happen more often than expected. Most incidents occur due to smouldering fires caused by technical problems such as over-heated engines, faulty turbochargers, locked brakes and defective tyres. In all these cases, visibility is quickly and drastically reduced.
Linear fire alarm cables usually installed in the tunnel cannot detect such incidents as they are triggered by increased temperatures, while video detection systems generate too many false alarms activated by light reflections from windscreens, change of contrast, etc.
Smoke detectors and visibility monitors are usually the first tunnel sensors that reliably detect a fire. The sooner a fire is detected, the earlier the emergency scenario can be initiated to give people more time to escape the danger zone.
JES tunnel sensors are designed for monitoring visibility, smoke and toxic gases such as carbon monoxide (CO) and nitric oxide (NO).
Cross-section air flow monitoring systems
Our ultrasonic t/FL-US monitoring system measures the airflow over the whole cross-section of a tunnel by evaluating the difference in the transition times of an ultrasonic pulse sent in one direction or the other.
This cross-section measurement delivers the air speed and direction more accurately than methods that only measure one or two points on the tunnel wall.
In a research project by the Swiss Federal Roads Administration, the t/FL-US was proven to be the most accurate and reliable measuring system in the test.
Scattered light visibility sensors
For the last 30 years, JES has promoted the installation of scattered light visibility sensors instead of the transmission-based sensors still used in many countries.
Scattered light photometers in a tunnel environment have many advantages such as:
- One device versus a transceiver and a reflector that have to be precisely aligned
- Effective compensation of contamination and ageing
- Easy compensation of fog by pre-heating of sample air (where indicated)
- A linear relation between instrument reading and visibility measure
Energy-saving road tunnel lighting
The tunnel lighting must be controlled so users can safely approach, pass through and exit the tunnel without changing the direction or speed.
The measured value of a luminance meter in front of a tunnel is used in many countries to determine the nominal lighting level for the tunnel entrance. However, as the actual value is not measured, several correction factors for maintenance, soiling, deterioration, etc. generally lead to situations where the actual lighting level is higher than required. Luminance meters installed inside the tunnel – in the threshold zone and interior zones – can contribute to saving energy.
The actual lighting level in modern light-emitting diode (LED) installations can be reduced to match the nominal value, leading to decreased energy consumption and longer life of the luminaires.
Sensor lifecycle support
Our experienced engineers tailor solutions for our customers’ applications and support them over the entire lifecycle.
This includes consulting, engineering, installation, commissioning, maintenance, repair and retrofit services.
Road weather stations
Weather influences road, air and rail traffic. For operators and users of the respective infrastructure, it is necessary to be aware of the prevailing weather conditions. Drivers may need to adapt to the conditions, and operators have to take measures to maintain traffic safety.
It is essential that sensors reliably and accurately determine the visibility and condition of the road or runway. Based on this information, operators can efficiently control roads or runways during adverse conditions, and drivers can be warned about slippery roads or reduce the speed limit.
JES delivers a scalable open weather station that connects sensors from various manufacturers, so road operators can choose the best sensor for the measurement.
Established in 1990, JES has vast experience in monitoring air and lighting conditions in multiple tunnels and underpasses.
Being a member of the DURAG GROUP, we offer a global sales and service network.
JES is headquartered in Austria.
Products and Services
t/LUM-A Luminance Meter
Adaptation of tunnel lighting to environmental lighting conditions.
t/ECS-A Gas Sensor
Air quality monitoring to improve safety in tunnels.
t/VIS-TR Visibility Monitoring System – Transmission
Air quality monitoring to improve safety in tunnels.
t/FL-US Ultrasonic Air Flow Monitoring System
Measurement of air speed and direction to control the tunnel ventilation.
t/FL-DP Air Flow Monitoring System
t/FL-DP is positioned at two points in a tunnel cross section and measures the longitudinal air flow.
Luminance and Illuminance
The aim of all tunnel lighting is to ensure that drivers approach, pass through and exit the tunnel without any change of speed or direction.
This JES Elektrotechnik whitepaper gives a brief explanation of photometry and its application in monitoring the visibility in tunnels.
Tunnel Hirschhagen, Germany
Da Nang – Quang Ngai Expressway
The Marieholm Tunnel is an immersed tube tunnel crossing underneath the Göta Älv in Gothenburg (Sweden).Read more
STRABAG Infrastructure & Safety Solutions was awarded a golden camera last Friday. The 3000th JES t/LUM-A tunnel luminance meter was handed over during a little party at the Gräberntunnel construction site.Read more
JES Elektrotechnik and DURAG Holding will work even more closely together in the future: as of January 2018, DURAG holds a 50% stake in the company.Read more