Designed for measuring temperatures up to 650°C, TDK has released an NTC sensor element offering high-precision measurement with a temperature tolerance of about ±1° at 200°C. The device is based on a high-temperature ceramic sensor element that is connected to a metallised aluminium oxide rod and then glass-encapsulated.
The 16mm long component obtains its particular ruggedness from the glass encapsulation, which has a diameter of 2mm. The sensor is available optionally with wires welded to the aluminium-oxide rod.
The high-temperature sensor is qualified to AEC-Q200 and designed for use in demanding automotive electronics applications such as in exhaust gas recirculation systems. These are used mainly on diesel engines to reduce excess oxygen in the combustion gas and thereby minimise the formation of nitrogen oxides at high combustion temperatures. In the recirculation systems the NTC sensors measure the temperature of the exhaust gas and thus help to protect the engine against overheating - in particular, the cylinder head and valve seats.
In e-mobility applications the sensors are able to monitor the temperature of fuel cells that are used in EV drive systems for the direct generation of electrical energy from hydrogen. Applications can also be found in household appliances, for example in self-cleaning ovens that operate on the pyrolytic principle. These work by heating the oven interior to a temperature of about 500°C which breaks down the long-chain molecules of the food residues and reduces them largely to gas and ash. The necessary temperature is regulated and stabilised by the NTC sensors.