Many industrial applications involve unique geometries, specialized mounting requirements, or extreme environmental factors that standard sensors cannot accommodate. Custom measurement sensors are engineered to specific technical drawings, providing tailored solutions for proprietary machinery. These sensors can be specified with unique sheath materials such as Inconel or specialized ceramic coatings to resist chemical corrosion or high pressure environments.

Wire probes consist of two dissimilar metals joined at a sensing junction, typically insulated with materials like PFA, fiberglass, or Kapton. These probes offer the fastest response times due to their low thermal mass. They are ideal for applications where space is limited or where a flexible sensor is required to reach internal components of a machine. Wire probes are commonly utilized in laboratory testing, electronic component monitoring, and HVAC duct diagnostics.

Needle probes feature a sharpened, small diameter stainless steel sheath designed for insertion into soft or semi solid materials. These are frequently used in food processing, chemical compounding, and rubber vulcanization processes. The pointed tip allows for internal temperature verification without causing significant structural damage to the material being tested. They are available in various lengths and diameters to suit different penetration depths.

Surface probes are engineered to measure the temperature of flat or curved solid surfaces through direct contact. To ensure accuracy, these sensors often utilize a spring loaded or high contact area sensing tip to minimize the effects of ambient air temperature on the reading. They are vital for monitoring motor housing temperatures, heat sink efficiency, and plate heat exchangers. High temperature handles are typically integrated to ensure operator safety during manual measurements.

High temperature thermocouples are manufactured using noble metals or specialized alloys capable of withstanding extreme thermal stress without melting or drifting in accuracy. Type R, S, and B thermocouples are commonly employed for temperatures up to 1800 degrees Celsius, while Type K and N are used for ranges up to 1300 degrees Celsius. These sensors are encased in high purity ceramic primary and secondary protection tubes to prevent contamination from furnace atmospheres.

Connection head thermocouples feature a rugged metal or plastic housing at the cold junction end. This head protects the electrical terminals from dust, moisture, and mechanical damage. It also facilitates the use of ceramic terminal blocks or integrated 4 to 20mA transmitters. This configuration is the industry standard for permanent installations in refineries, power plants, and chemical processing facilities where sensors must be wired into a centralized control room via conduit.