Urea Dosing Sensor For On & Off-Highway Equipment

Posted on October 15, 2008

Kavlico, Moorpark, Calif., has developed a new sensor for selective catalytic reduction (SCR) systems that will be used in most 2010 heavy-duty trucks in North America, as well as off-highway equipment.

The urea dosing sensor is designed to provide feedback to the system controller and assist in optimizing the reduction of NOx emissions by monitoring the SCR system and helping to determine the appropriate amount of aqueous urea reducing agent to be delivered to the catalytic converter module.

The urea-dosing pressure sensor utilizes Kavlico’s patented ceramic capacitive sense element for pressure ranges up to 363 psi (25 bar) and a thin film (TiON) sense element for pressure ranges above 363 psi (25 bar). The sensor is packaged in an all stainless-steel housing. Requiring a 5 Vdc power supply, the sensor provides a 0.5 to 4.5 Vdc linear amplified analog output proportional to pressure.

Other significant features of the sensor include the ability to operate in high-vibration environments, the capability to withstand high overpressures, and operate over a temperature range of -40° to + 266°F, Kavlico said.