Operating Manual

IRS31Pro-UMB Operating Manual V10 / 01.2020
G. Lufft Mess- und Regeltechnik GmbH 8
4 Equipment Description
Depending on the requirements of the road traffic meteorological monitoring network, sensors are
installed in the roadways and / or "overhead". The Lufft IRS31Pro-UMB is intended for installation in the
roadway. The passive measuring instrument IRS31Pro-UMB is used to determine the road surface
temperature, the height of the water film above the sensor and the saline concentration on the sensor
(from which the freezing temperature is derived). The built-in road condition models use these variables
to determine the corresponding road conditions.
The sensor provides the following established and commonly used decision-making data for winter
maintenance services: water film height, road condition, road surface temperature and freezing
temperature. In addition, the sensor delivers an ice percentage reading. As the ice percentage increases
on the surface, the friction coefficient falls and this can then be used to support preventive gritting
decisions.
Depending on the sensor type, up to 2 below-ground temperatures can be measured, preferably at
depths of 5 cm and 30 cm.
The equipment is connected by way of a 4-pin connection cable (with a length of 50 m or 100 m,
depending on the type).
The measured values can be requested over the RS485 interface in accordance with the UMB protocol.
During commissioning, configuration and verification takes place using the UMB Config Tool
(Windows®PC software).
4.1 IRS31Pro-UMB Sensor
Figure 1: Sensor
Below-ground
temperature 1
Depth 5 cm
Below-ground
temperature 2
Depth 30 cm
Conductivity
measurement
Temperature measurement
Water film height measurement