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EngineSens Motorsensor GmbH

Mannheimer Str. 44 b

E-Mail  info@enginesens.com

D-68519 Viernheim / Germany

phone  +49 6204-986 08 23

fax       +49 6204-986 08 25

Sensing the future

Our Portfolio:

Temperature Probes, Differential Pressure Sensors for Particle Filters, Airflowmeters, NOx-Probes and consultancy regarding Exhaust Gas Purification and Exhaust Gas Sensors.




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NOx 0-1500 ppm 24 V small

NOx-Probe  24 V 1500 ppm

Our NOx-sensor is a reliable heavy-duty version of common components used in passenger cars. As it is a heavy duty version the life-time expectance is much longer. It can measure from very low levels of NOx up to 1500 ppm. Mainly it is used in marine diesels that are running in the ECAs of the Baltic and North Sea. Further applications are in the emission monitoring of stationary engines. The sensor principle is based on several cavities. In the first cavity the exceeding oxygen is pumped away, In the second cavity two electrodes measure a very low voltage signal that is created by reforming the NOx-content. As those currents are at a minimmum level the distance of the sensor tip to the controller is limited to 59 cm. There is a big cross-sensitivity between ammonia and NOx. Up to a level of 300 ppm it is not possible to distinguish

between both gases. Furtheron the sensor is sensitive against moisture and vapor. After starting the sensor it heats up to approximately 90C and waits for the dewpoint bit. As soon as the dew point bit has been sent by CAN-bus the ceramic will be heated up to 800C. Usually after starting the engine some seconds or even better some minutes should pass by before the dew point bit is sent. Condensating moisture on the ceramic surface will destroy the sensor immediately. Due to the oxygen pumping system it is only possible to determine a NOx-content under lean conditions. It is not possible to use the sensor in Lambda = 1 engines or in gasoline engines running rich.



measuring principle

ZrO₂-based multilayer-sensor

output signal

NOx - content / binary lambda (lean/Rich) / linear lambda

supply voltage



CAN 2.0 Standard-Bus (250 kBaud, 50msec repetition)


detection open and short circuit

Exhaustgastemp.- range


measuring range for NOx

0-1500 ppm

accurancy NOx signal

@ 500 ppm 10%; @ 0 ppm 10 ppm

measuring range for oxygen

ƛ = 0,75… air

order code

Art.-Nr. 70501


Art.-No. 70550 connector kit NOx / Art.-No. 40102 welding socket SO-NOx M20x1,5

drawing part No. 70501 as PDF