TDC3 Traffic detectors

Non-intrusive traffic detectors for single lane traffic data acquisition

The TDC3 Series are advanced traffic detectors using Doppler Radar, Ultrasound and Passive Infrared technology. Comprehensive traffic data including individual vehicle class, speed, length, occupancy time and time gap are provided via RS 485.


TDC3 Series detectors are specifically designed for a variety of Traffic Data Collection and traffic control applications where inductive loops have been used in the past:

  • Vehicle classification
  • Individual vehicle speed
  • Vehicle counting (volume)
  • True presence, queue and wrong-way driver detection
  • Occupancy and headway / time gap measurement


TDC3 traffic detectors measure the speed of each vehicle using the Doppler shift of the reflected microwave frequency. The ultrasonic sensor system scans the height profile of the passing vehicle and the PIR zones obtain the vehicle position (except TDC3-2) within the observed lane.


Recommended mounting points are gantries or other overhead structures above the lane centre. Clearly superior performance and reliability are a result of:

  • Three independent detection technologies
  • Full temperature compensation across entire temperature range
  • Redundant system functionality
  • Multi technology detection: Three independent physical detection principles
  • Standardized vehicle classification: German TLS for 2, 5+1 and 8+1 classes
  • Auto calibration: Via according installation software within the recommended height above the lane
  • Detection of lane-changing vehicles and vehicles travelling between adjacent lanes (except TDC3-2)
  • Detection of standing vehicles
  • Detection of wrong-way drivers
  • Wide operating temperature range (–40 to +70°C): Optimum performance in all weather and climate conditions
  • Remote configuration and setup: With according installation program

Supply Voltage

10.5 … 30 V DC

Power Consumption

max 110 mA
typ. 80 mA @ 12 V DC

Output (Data Transfer)

RS 485 (other options on request)

Turn-on Time

typ. 20 s from power on


see drawing (pictures tab)

Case Material

Polycarbonate, dark grey

Mounting Points

M8, stainless steel V4A


app. 1700 g (3.75 lbs) without bracket

Doppler Radar

K-Band 24.05 … 24.25 GHz

Ultrasonic Frequency

40 kHz

Ultrasonic Pulse Rate

10 … 30 pulses per second

PIR Sensors

2 channel PIR (TDC3-2)
7 channel PIR curtain (TDC3-3 /-5 /-8)

PIR Spectral Response

6.5 … 14 μm

Counting accuracy

typ. ± 3%

Speed accuracy

typ. ± 3% (> 100 km/h)
typ. ± 3km/h (≤ 100 km/h)

Classification accuracy

Vehicle classes according TLS
The specifications refer to free traffic flow,
detector operated in recommended setup.

Operating Temperature

-40°C to +70°C (-40 to +158ºF )


95 % RH max.


IP 64 splash proof