Vibration-related problems in a PT100 measurement channel can come from the probe mounting, lead wires, connector, terminal, instrument input, or the measurement location. A PT100 element name alone does not establish that the complete assembly is suitable for a vibrating machine.
This guide helps OEM engineers review a platinum RTD for vibration exposure. It focuses on failure prevention through application definition, mechanical integration, wiring, and representative validation—without assuming that every sensor construction has the same vibration capability.
Identify where vibration acts on the assembly
Document the equipment, sensor location, motion or vibration source, operating states, temperature profile, mounting support, and expected service conditions. Use the equipment drawing to identify how the probe is supported and whether the cable or connector can move relative to it. A sensor mounted on a motor winding, bearing area, enclosure, or pipe experiences different mechanical and thermal conditions.
Review the full load path from the sensing tip through the sheath, fitting, lead transition, cable, connector, and instrument terminal. Repeated movement or contact can loosen a fitting, damage insulation, fatigue a conductor, alter thermal contact, or create an intermittent connection. The mechanism must be confirmed on the actual design; vibration exposure does not imply that every PT100 will fail in the same way.
Specify the RTD and input interface
State the nominal resistance, reference temperature, resistance–temperature curve or standard, tolerance, wiring arrangement, and receiving instrument. Confirm that the controller is configured for the actual PT100 curve and lead scheme. Two-wire, three-wire, and four-wire circuits compensate for lead resistance differently; specify the cable and connection details used in the equipment.
Include the operating range, sheath material and dimensions, insertion length, mounting method, cable length, insulation, connector, and available clearance. Do not use a general “vibration-resistant” label as a substitute for a defined assembly and test requirement.
Review mounting and cable routing
- Use a support and fitting compatible with the equipment drawing and expected movement.
- Prevent the cable from carrying unintended mechanical load at the probe transition or connector.
- Provide strain relief and bend routing that match the installation and service movement.
- Keep the sensing point and thermal contact consistent with the defined measurement objective.
- Check that the connector, terminal block, and enclosure remain secure during operation and maintenance.
For high-consequence installations, agree how the assembly will be evaluated under representative vibration and thermal conditions, and define pass/fail criteria before sample testing. A generic test result for a different probe, fixture, frequency profile, or mounting arrangement may not represent the installed design.
Diagnose intermittent or shifted readings
Record whether the symptom follows vibration, startup, speed changes, temperature cycles, or maintenance. Inspect the fitting, lead transition, cable, connector, and terminals. Confirm sensor wiring and controller configuration; then compare the installed channel with a suitable reference under stable, repeatable conditions. Where the site procedure allows, determine whether the symptom follows the sensor, cable, input channel, or installation.
Separate mechanical connection problems from element drift or a persistent calibration offset. If the installation changes the probe’s contact or location, the indicated temperature can change even when the RTD response has not. Document test conditions and instrument setup before replacing the element.
OEM project checklist
- equipment drawing, measurement point, and vibration source;
- PT100 curve, tolerance, wiring, instrument input, cable and connector;
- probe dimensions, mounting support, strain relief, and service routing;
- representative test fixture, operating profile, acceptance limits, and records;
- approved drawing revision, sample approval, and change-control process.
See the RTD sensor assembly range, the motor PT100/PT1000 example, and our RTD supplier evaluation checklist. For an application-specific review, send the assembly drawing and operating conditions.
