t/FL-USX Air Flow Monitoring System

JES t/FL-USX Ultrasonic Cross Section Air Flow Monitoring System

Features

Precise ultrasonic air flow measuring system based on different transition times of ultrasonic pulses
Measurement of average air-flow over the whole tunnel cross section
Sensor setup via service interface
Suitable for tunnel cross sections up to 18 m
(Measuring path up to 25 m)
Connection to tunnel control system either via analogue output and relays or via RS 485 MODBUS RTU
Visible LEDs to indicate sensor status
Optional, remote smart/HUB touch operation unit to display measured values and to modify parameters

System setup

Two sensors (master & slave) with mounting clamps mount-ed below the tunnel ceiling in an angle of 30° to 60° to the tunnel axis
Terminal box for master to connect the power supply and the connections to the tunnel control system and the slave
Terminal box for Slave
Optional remote smart/HUB touch operating unit

Operation

The air flow monitoring system measures the air flow based on different transmission times of ultrasonic pulses sent in one or the other direction. This cross section measurement delivers the average air speed more reliable and mean-ingful than methods that measure only one or two points on the tunnel wall.

Two sensors are mounted below the tunnel ceiling, cross section with an angle of 30° to 60° (usually 45°) such that a vector component of the air flow overlaps the direction of the ultrasonic sound pulses exchanged by the two sensors.

Air flow in the tunnel influences the transition time of the pulses be-tween sender and receiver. Based on the difference in transition times of ultrasonic pulses sent in one or the other direction the measured values are calculated.

Measured values are air speed, air flow rate, direction of air flow and air temperature.

Advantanges

Specifically developed for application in tunnels
No control unit required
Easy configuration
Corrosion resistant against aggressive tunnel atmosphere
Sensors can be replaced quickly with no tools and no re-alignment required
Minimised spare requirements
Extremely low maintenance requirements

Application

Tunnels are important infrastructure elements in road networks and facilitate the connection of regions.

Environmental conditions in tunnels are influenced by fog, particles and emissions and need to be monitored to protect people on their passage through the tunnel from danger and impacts on their health. Accidents in tunnels, and particularly fires, can have dramatic consequences and can prove extremely costly in terms of human life, increased congestion, pollution and repair costs. At every time people in the tunnel need to be supplied with breathable air and sufficient visibility.

Since 1990 JES Elektrotechnik GmbH develops, installs and maintains systems to monitor air characteristics and lighting conditions in tunnels. Our systems are robust, durable and resistant against the corrosive atmosphere in a tunnel. They operate reliably and have a high accuracy in measurement.

All systems fulfil the requirements of the EC guideline 2004/54/EC (Minimum safety requirements for tunnels in the trans-European road network) and the more detailed national guidelines and provisions:

Austria: RVS 09.02 Tunnelausrüstung
Germany: RABT Richtlinien für die Ausstattung und den Betrieb von Straßentunneln
Switzerland: ASTRA Richtlinien und Fachhandbuch Betriebs- und Sicherheitsausrüstungen (BSA)

Our range of products for tunnel covers systems for monitoring of

Visibility (extractive or in-situ)
Toxic gases like CO, NO, NO₂ (extractive or in-situ)
Air velocity, direction and temperature
Luminance (access, threshold and interior zone)
Illuminance

Technical Specifications

Air flow measurement
Type	JES t/FL-USX
Measuring method	Determination of direction dependant differential transi-tion times of ultrasonic pulses
Measured values	Air speed Air flow rate Direction of air flow Air temperature
Measuring range	-40 .. 40 m/s
Resolution	0.1 m/s, accuracy depending on measuring distance, flow profile, installation, typically <±0.2 m/s at 3 m/s
Response time	> 1s … 180 s, configurable
Measurement path length	1.2 - 25 m
Alignment	30 - 60° to tunnel longitudinal axis, typically 45°

Outputs
Analogue output	1 x 4-20 mA, 400 Ω, isolated can be assigned any measured value and output range
Output range	configurable, typically: -20 to 20 m/s
Relay contacts	1 x fault indication (NC) 1 x direction of air flow (NC) (max. 48 V / 0.5 A)
Digital interfaces	1x RS 485 MODBUS RTU to control system, bidirectional 1x Intercom RS 485 master-slave

Ultrasonic transceiver (sensor)

Sensor
Type	DURAG D-FL 220T M
Operating voltage	24 VDC ± 10 %
Current consumption	1 A
Appliance class	Class III
Service interface	USB 1.1
MTBF	> 170.000 h within service life if used within specifications
Material	Sensor housing: Polyamide RAL5017, Flammability rating: B1 (UL 94 V0) Wall bracket: Stainless steel 1.4404 (AISI 316L) or 1.4571 (AISI 316Ti)
IP rating	IP 69
Dimensions	270 x 130 x 95 mm
Weight	Sensor 2.2 kg Wall bracket 1.6 kg
Indoor/Outdoor use	Indoor use (tunnel)
Altitude	up to 2,000 m
Temperature range	-40 .. +70 °C
Humidity range	0 .. 100% relative humidity (non-condensing)
Pollution degree	4 (intended environment)

t/FL-USX-TBX terminal boxes

Terminal box A - JES t/FL-USX-TBX-A
Type	t/FL-USX-TBX-A
System cable port	1 (for D-FL 220 T M Sensor A)
Power supply	100 to 240 VAC, 50/60 Hz
Supply voltage fluctuations	± 10 %
Overvoltage category	II
Power rating	60 W
Appliance class	Class I
Material	Stainless steel 1.4404 (AISI 316L)
Mounting	incl. mounting clamp made from Stainless steel 1.4404 for wall mounting
IP rating	IP 69
Dimensions	250 x 160 x 110 mm
Weight	approx. 3.2 kg
Indoor/Outdoor use	Indoor use (tunnel)
Altitude	up to 2,000 m
Temperature range	-40 .. +60 °C
Humidity range	0 .. 100% relative humidity (non-condensing)
Pollution degree	4 (intended environment) / 2 (when cover removed)

Terminal box B - t/FL-USX-TBX-B
Type	t/FL-USX-TBX-B
System cable port	1 (for D-FL 220 T M Sensor B)
Power supply	24 VDC ±10 %
Current rating	1 A
Appliance class	Class III
Material	Stainless steel 1.4404 (AISI 316L)
Mounting	incl. mounting clamp made from Stainless steel 1.4404 for wall mounting
IP rating	IP 69
Dimensions	160 x 160 x 110 mm
Weight	approx. 1.9 kg
Indoor/Outdoor use	Indoor use (tunnel)
Temperature range	-40 .. +60 °C
Humidity range	0 .. 100% relative humidity (non-condensing)
Pollution degree	4 (intended environment) / 2 (when cover removed)

smart/BOX-S-FL-USX gateway (instead of t/FL-USX-TBX-A for Ethernet connection)

smart/Architecture gateway for t/FL-USX - smart/BOX-S-FL-USX
Type	smart/BOX-S-FL-USX
System cable port	1 (for D-FL 220 T M sensor)
Power supply	100 to 240 VAC, 50/60 Hz
Supply voltage fluctuations	± 10 %
Overvoltage category	II
Power rating	60 W
Appliance class	Class I
Digital interfaces	MODBUS RTU (RS-485) MODBUS/TCP (Ethernet) Webserver for configuration (Ethernet)
Material	Stainless steel 1.4404 (AISI 316L)
Mounting	incl. mounting clamp made from Stainless steel 1.4404 for wall mounting
IP rating	IP 69
Dimensions	250 x 160 x 110 mm
Weight	approx. 3.2 kg
Indoor/Outdoor use	Indoor use (tunnel)
Altitude	up to 2,000 m
Temperature range	-40 .. +60 °C
Humidity range	0 .. 100% relative humidity (non-condensing)
Pollution degree	4 (intended environment) / 2 (when cover removed)

Conformities

Conformities
Markings
Electrical standards	2014/35/EU Low Voltage Directive (LVD) 2014/30/EU Electromagnetic compatibility (EMC) EN 61010-1 Safety requirements for electrical equipment for measurement, control and laboratory use EN 61326-1 Electrical equipment for measurement, control and laboratory use - EMC requirements
Tunnel safety standards	Austria: RVS 09.02.22 Germany: RABT 2006 Switzerland: ASTRA RL 13001, Fachhandbuch BSA Norway: Norwegian Public Roads Administration Handbook No. 021 Road Tunnels International: ISO 23431 Measurement of road tunnel air quality