Cable Probes

Cable Probes

Cable probes are compact RTD and thermocouple (TC) thermometers supplied with a non‑removable, flexible connection cable. They are offered as plug-in sensors without a process connection, or with common connections such as compression fittings and threaded adapters, with additional options that support specialized mounting (e.g., weld-on pads or bayonet-style retention). The probe sheath is placed in direct contact with the process medium, which keeps the sensing element closely coupled to the measured temperature.

The primary value of a cable probe is installation flexibility without sacrificing measurement performance. A small-form sensor with a bendable cable can be routed through crowded equipment envelopes and around obstructions where rigid stems or large heads are impractical. Direct medium contact supports fast thermal response and high fidelity in dynamic processes, while the compact build helps standardize measurement points where space and access are limited.

Configuration breadth is typically driven by sensor type and materials. Single or dual RTD/TC elements can be selected to balance redundancy, diagnostics, and accuracy requirements. Sheath and cable materials (including mineral-insulated and connection-cable variants) are chosen to align with temperature range, chemical compatibility, mechanical abrasion, and flex requirements. Environmental protection and hazardous-area suitability are addressed through available approvals and ingress protection classes such as IP66/67.

Typical applications favor difficult geometries and “hard-to-instrument” locations: machinery and skids, HVAC equipment, storage temperature monitoring, laboratory devices, autoclaves, bearings, and installations that must accommodate bending at the measurement location. Cable probes are also used in demanding services such as high-pressure or cryogenic duty, and can be applied to surface temperature monitoring on reactors where routing and access drive sensor form factor.

Selection is generally anchored by measurement principle (RTD for high accuracy and stability versus TC for higher temperature capability and ruggedness), then refined by the required process connection, insertion geometry, materials, and certification needs. In the Endress+Hauser portfolio, iTHERM CableLine variants are positioned to cover these combinations while keeping the assembly compact and adaptable to site constraints.

Forberg Smith, an exclusive authorized representative of sales and service for Endress+Hauser.