Thermocouple exhaust gas temperature sensor

Paul Boughton

Watlow, a designer and manufacturer of electric heaters, controllers and temperature sensors, introduces the EXACTSENSE thermocouple for high temperature exhaust gas temperature sensing.

EXACTSENSE combines the durability and high temperature capability of a thermocouple with integrated electronics in a proven package delivering the accuracy and response time needed to meet the most demanding applications.

The sensor was developed with several leading original equipment manufacturers (OEMs) in the United States and Europe for the use on exhaust after-treatment systems on diesel engines. This accurate, durable sensor can be used on after-treatment systems for both off-road and over-the-road vehicle diesel engines including construction, heavy duty, mining and agriculture vehicles as well as marine, locomotive and stationary power generation applications. 

EXACTSENSE has an electronic housing with an integrated molded connector that is available with either an analog or digital output signal. Combining the sensor and the electronics provides an output signal compatible with engine control modules (ECMs), minimizes system error because the sensor and the electronics are integrated and enables the use of information about the sensor such as sensor identification, serial number, calibration, drift, time response data and more to enhance the performance or improve diagnostic capabilities.

It uses non-standard thermocouple materials that were selected based on their stability, durability and longevity at high temperatures. EXACTSENSE is accurate within ±8°C (±14.4°F) from -40 to 1000°C (-104 to 1832°F).

This thermocouple is said to have the longest immersion depth available on the market and is point sensitive compared to RTDs that average the temperature over the length of the element. This enables measurements to be taken near the center of the pipe, whereas many competing technologies fall short. The taper tip configuration of the EXACTSENSE thermocouple delivers industry leading response time in a durable closed tip configuration, which increases the life of the sensor and ensures better system control. These features help Watlow customers improve the control of their diesel after-treatment systems, resulting in improved emissions, more efficient regeneration and better fuel economy.

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