Bearing temperature sensors for rotating machinery protection

Bearing temperature sensors give operators an early warning when lubrication, alignment, load, or cooling problems start driving bearing metal temperature upward.

Thermometrics builds RTD and thermocouple bearing sensors for motors, turbines, turbo machinery, pumps, generators, and other rotating equipment, with case styles, lead exits, armor, and cable routing selected around the actual housing geometry and clearance limits.

In turbine and turbo machinery service, bearing temperature is a protection signal as much as a process reading. Sensor fit, contact pressure, lead protection, and routing through the frame all affect how quickly a protection system can identify lubrication loss, rub, overload, or cooling issues before bearing damage progresses.

Common Configurations

RTD sensing in platinum 100 ohm (Pt100) or platinum 1000 ohm (Pt1000), or thermocouple sensing
Single or dual element builds
Case styles A, B, C, and D with top, side, or rear lead exit options
Lead wire options for abrasion, heat, and routing demands

Key Advantages

Spring-loaded sensing formats to maintain thermal contact at the measurement point
3-wire RTD options compatible with common PLC and DCS analog input schemes
High-accuracy RTD and thermocouple-based builds for predictive maintenance and protection
Turbine and turbo machinery builds for bearing metal temperature monitoring, generator protection, and rotating-equipment shutdown logic

Bearing temperature sensor options with stainless and copper contact styles

Bearing thermocouple and RTD contact-style sensor examples.

Typical bearing housing inserts including Babbitt material and RTD insert detail

Typical bearing housing inserts and curved bearing-contact builds.

Case Style Types

Bearing Sensor Case Style Guide

Case style is selected from the bearing housing geometry, available insertion depth, contact requirement, and element or wire configuration shown on the drawing or RFQ.

Type A 0.250 in. L x 0.275 in. Dia. 6.4 mm x 7.0 mm Compact cylindrical case with a short sensor body and larger contact face.
Type B (Top Hat) 0.250 in. L x 0.188 in. Dia. 6.4 mm x 4.8 mm Spring-loaded top hat case style with external retention hardware for maintained bearing contact.
Type C 0.300 in. L x 0.125 in. Dia. 7.6 mm x 3.2 mm Small-diameter cylindrical case for narrower bearing housing or bore requirements.
Type D 0.300 in. L x 0.080 in. Dia. 7.6 mm x 2.0 mm Reduced-diameter probe-style case for limited insertion space and compact single-element builds.

How to Choose the Right Bearing Sensor

RTD bearing sensors with platinum 100 ohm (Pt100) or platinum 1000 ohm (Pt1000) elements for stable machine protection loops
Thermocouple-based builds where faster response or existing TC instrumentation is preferred
Bearing thermocouple assemblies selected around the case style, contact geometry, lead exit, and machine-protection requirements
Single and duplex builds for redundancy, control, and shutdown logic

Information to Share for Quoting

Bearing housing style, available clearance, and preferred case geometry
Whether the sensor is protecting turbine, turbo, generator, or other critical rotating-equipment bearings
Lead exit direction, wire protection, and routing constraints through the machine frame
Required sensing technology, wiring scheme, and instrument interface
Contact-tip shape, spring force, and installation environment around oil, vibration, and heat

Browse Bearing Sensor Product Pages

Choose the bearing sensor style that best matches the sensing technology, case style, and machine-protection approach used in your rotating-equipment program.

BTC Bearing Thermocouples

Bearing thermocouple assemblies for motors, turbines, turbo machinery, pumps, fans, gearboxes, and other rotating equipment.

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BRTD Bearing RTDs

Platinum 100 ohm (Pt100)-based bearing RTD assemblies for stable machine protection loops and API 670-oriented applications.

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Industries Where Bearing Sensors Are Common

Bearing temperature monitoring is usually tied to rotating-equipment reliability programs in these industries.

Industrial Machinery

Motors, gearboxes, and driven equipment where machine health and replacement fit matter.

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Energy & Power

Fans, pumps, turbine-adjacent equipment, and other critical rotating assets.

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Automotive & EV

Specialized rotating test stands, validation rigs, and machinery temperature points.

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Request a Bearing Sensor Quote

Provide bearing style, mounting method, lead length, range, and preferred sensor type (RTD or TC).

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