Emissions from Scania trucks and buses are measured under real-life traffic conditions. The company has three mobile test labs for making sure all of its vehicles meet Euro 6 standards.
From the outside it looks like an ordinary trailer hitched to a Scania P 360 tractor. But the 10-foot container is crammed with equipment for measuring emissions. It is one of three mobile test labs operated by Scania.
Emission tests carried out in real-time
Sven Andersson, emission test engineer at Scania, says: “With these labs we can check the emissions from at least 50 vehicles per year. Most of the tests are conducted on tractor units to which we can attach the trailer with the mobile test lab. But we can also use these labs for rigid trucks as well as buses and coaches.”
Previously, heavy vehicle manufacturers used stationary test rigs to check emissions. But the Euro 6 regulations, which came into effect in December 2013, require tests to be carried out under normal traffic conditions. Accordingly, the Scania trucks are also loaded with ballast corresponding to 50 to 60 percent of their payload.
“We perform on-road analyses on at least one customer vehicle per month,” Andersson says. “Furthermore, we test vehicles during the development and production phases. We also test trucks in our own transport operations.”
Tests designed to reflect real conditions
Each test run takes between three to four hours and is designed to be as realistic as possible.
“This means we drive on city, rural and highway roads,” Andersson says. “The idea is to measure emissions in normal traffic under normal conditions.”
Once a test lab has been attached to a tractor it is connected to the vehicle’s on-board diagnostics system and an exhaust gas analyser is mounted on the tailpipe.
Several parameters monitored
“Using a laptop we then get readings on different emissions: carbon monoxide, carbon dioxide, hydrocarbons and nitrogen oxides,” Andersson explains. “We can also see the exhaust flow, exhaust temperature and exhaust pressure, as well as GPS data and weather data, such as temperature and humidity.”
The test engineers can also access any other relevant data: engine speed, vehicle speed, engine temperature, torque, and fuel consumption.
“Thanks to our mobile test labs we can control that Scania vehicles meet Euro 6 standards for on-road emissions,” Andersson says.