Tractors, harvesters, combines, bulldozers, excavators, drilling machines, crushers, forklifts, and other mobile machines typically work under very harsh conditions. Monitoring the temperature of their systems helps to ensure lasting performance and minimal downtime.

Electrical temperature probes are one of the most common devices used for measuring temperature in these types of applications. The sensors in the probes are generally resistance temperature detectors (RTDs). The resistance of RTDs varies with temperature, and since the temperature-resistance relationship is known, it is a convenient and reliable way to measure temperature.

RTDs for mobile working machines are usually made of a pure metal such as platinum or nickel and are passive devices that do not require a power source. The cost of RTDs is relatively low compared to other temperature measurement technologies and they are durable with a very long life span. Depending on the application, you can mount an electrical temperature probe on the surface of the system to be measured, or you can insert the probe directly into the process. Both configurations are good options to monitor temperature in tanks, reservoirs lines, pumps, motors and radiators of mobile working machines. WIKA has developed a variety of electrical temperature probes using RTDs to satisfy the different needs of the mobile machinery industry.

Types of Electrical Temperature Probes



WIKA’s insertion probes, such as the TF43 model, come with a hot rubber coated sensor and cable for watertight protection, and are available with single or double insulated lead wires. They measure temperatures from -58°F to +221°F, and come with flying leads or an electrical plug connector according to customer specifications. Surface electrical temperature probes eliminate potential leak paths and fluid contamination.

WIKA’s surface probe TF44, for example, is very easy to install and can be mounted in tight places. Its small aluminum sleeve provides excellent thermal transfer and fast temperature response times. It comes with flying leads or electrical plug connectors, and its design allows it to measure higher temperatures that range from -58°F to +392°F. WIKA also offers screw-in electrical temperature probes with either electrical plug connections, such as in model TF35, or an integrated silicone cable directly connected to the body of the sensor, like that of model TF37.


These compact designs come in a variety of materials, dimensions, connections, and sensors. Screw-in electrical probes have high resistance to vibration and extremely high resistance to shock, which make them perfect for modern mobile machines. WIKA has a full line of probes, switches, and transmitters to measure hydraulic, engine, transmission, and other system temperatures in mobile machinery normally used in agriculture, construction, mining, and material handling. WIKA has specifically designed its electrical temperature probes to withstand the harsh environments most frequently associated with these mobile working machines. WIKA offers customers almost unlimited possibilities, designing probes to meet specifications and provide optimal performance for each application.

WIKA’s experts can help you evaluate your application, look at the advantages and disadvantages of the available solutions, and can guide you through the selection of the most appropriate temperature measurement instrumentation.

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