Mounting the Sensing Element

Make sure that the engine is switched off while mounting and that the EasyNOₓ system is not live. Also make sure that the exhaust pipe has cooled down sufficiently and that there are no exhaust gases in the exhaust pipe.

The sensing element of the NOX sensor is screwed into the exhaust pipe via the supplied stainless steel welding boss (material number 1.4301) from MOTORTECH. The supplied locking screw is used for closing the welding boss if you no longer want to use the opening or close it temporarily, and as a welding aid for the welding boss.

Proceed as follows:

  1. At the selected mounting position in the exhaust pipe, drill a hole with a diameter of 27 mm ± 1 mm (1.07" ± 0.04") into the exhaust pipe.

    01_Neigungswinkel-horizontal

  2. Screw the supplied locking screw into the supplied welding boss and weld the stainless steel welding boss (material number 1.4301) into this hole with a suitable welding filler.

    01_Neigungswinkel-horizontal

  3. At the mounting position of the sensing element, determine the NO2/NOX ratio (correction factor K) in the exhaust gas with a suitable calibrated exhaust gas analyzer. More information on this is available in the section Determining the NO2/ NOₓ Ratio.
  4. Remove the protective cap from the probe of the sensing element. Do not pull on the connection cable, but hold the sensing element only by its metal body.
  5. Check whether the thread of the sensing element is sufficiently greased. If necessary, re-grease only the thread of the sensing element with a small amount of high temperature grease (Optimol Paste MF from Castrol® or Never Seez Regular Grade from Bostik®, recommendation 40 mg ± 10 mg). Also make sure that no dirt, dust, or grease gets deposited in or on the probe while mounting.
  6. Insert the sensing element into the welding boss and screw the sensing element into the welding boss via its hexagon nut by hand first. The outgoing wires must not twist in the process. Therefore counter the sensing element with your hand.
  7. Then tighten the sensing element over its hexagon nut using a calibrated torque tool with a torque of 60 Nm ± 10 Nm (44.3 lb-ft ± 7.4 lb-ft).

    01_Neigungswinkel-horizontal

  8. Then lay the connection cable between the sensing element and the evaluation unit of the NOX sensor. When doing so, comply with the specifications in the section Laying the Connection Cable.
  9. Later, when configuring the EasyNOₓ, enter the NO2/NOX ratio determined above in the NOX Setup view of the respective NOX monitor (see section Preferences).
  10. Also, when configuring the EasyNOₓ, enter the sensor-specific factor KNO2 for the corrective calculation of the NO2 sensitivity in the NOX Setup view of the respective NOX monitor (see section Preferences). For the correction factor, refer to the entry NO2 Gain in the NOX Sensor view of the respective NOX monitor (see section Sensor).