Euro 5 and Euro 6 are both sets of standards introduced by the European Commission (EC) to reduce harmful emissions from vehicle exhausts. Having a NOx sensor is key to helping your vehicle comply with these standards.

What is Euro 5 and Euro 6?

Euro 5 and Euro 6 are both sets of standards introduced by the European Commission (EC) to reduce harmful emissions from vehicle exhausts. Having a NOx sensor is key to helping your vehicle comply with these standards.

Euro 5 focuses on reducing carbon dioxide (CO2) emissions, having made it compulsory for diesel vehicles to have a Diesel Particular Filter (DPF) fitted by January 2013. Euro 6, on the other hand, focuses on reducing nitrogen oxide emissions. It has taken a stricter stance towards diesel engines, particularly in terms of NOx emissions, forcing manufacturers to reduce a vehicle’s output by 55%.

A limit of 60mg/km was set for the NOx output of petrol vehicles when Euro 5 was introduced, whilst the limit for diesel vehicles was 180mg/km. When Euro 6 was introduced, the NOx limit for diesel vehicles decreased to 80mg/km.

When it became compulsory under Euro 5 emission standards for vehicles to be fitted with a Diesel Particulate Filter (DPF), demand for accurate NOx measurements increased. Fitting a vehicle with a DPF is vital for the reduction of pollutant gasses.

A simple DPF is key to complying with both sets of standards, they can trap particulates and burn them off when the exhaust gases reach high temperatures during high speeds. Under this system, AdBlue is injected through a catalyst into the exhaust of a diesel vehicle. AdBlue breaks down mono-nitrogen oxides, converting nitrogen oxide into vapour and nitrogen which are then expelled through the exhaust pipe.

What is a NOx sensor, and how does it work?

A Nitrogen Oxide (NOx) sensor can be a part of the catalyst within a DPF. It provides quick and reliable measurements of the concentration of NOx gas emitted from engines, and monitors catalyst performances and oxygen concentration.

Readings provided to the SCR system determine how much AdBlue needs to be injected into the exhaust system. During the process, oxygen is extracted before nitrogen oxides are broken down.

Sometimes an electrode is used, containing a catalyst made from activated carbon, titanium oxide, and other base metals. A voltage is sent to the SCR system after the catalyst reacts with nitrogen oxides. Alternatively, a sensor can work by eliminating oxygen in the exhaust gas so that the concentration of NOx can be analysed.

Setting up the NOx sensor

When placing your NOx sensor in your truck, it is important to keep it well positioned and protected to ensure that you get the best usage out of the device. Here are a few things to bear in mind:

·         The sensor must be in a position that keeps it away from water so that it doesn’t reach the probe. Moisture and a build-up of ice will cause damage.

·         To protect your sensor, it must be positioned no more than 80º from the vertical plane to prevent water from gathering.

·         The sensor must not be placed on flexible pipe parts, and it should be positioned as far away from them as possible.

·         To ensure your sensor provides the correct values, make sure its longitudinal axis doesn’t deviate any more than 10º from a right angle to the exhaust flow. If the angle is too large or small, it will disrupt the gas flow.

Where can I buy a NOx sensor?

Is your truck in need of a NOx sensor? At Truckspares 365 we strive to help you get the best out of your truck and we’re highly regarded by our customers, having been in the industry for over 40 years. We sell NOx sensors for trucks from many different manufacturers including DAF and Scania. We have arranged our NOx sensors by vehicle and product brand to make your search easy. If you need any further assistance, however, please don’t hesitate to give our sales team a call on 01772 287813 or email [email protected] with your enquiry – we would love to hear from you.