When Extreme Heat Threatens Machine Protection
A reactor coolant pump in a nuclear plant was tripping on false vibration alarms. Standard accelerometers failed above 300°C, leaving operators blind to real loose-part events. The fix was a sensor built for the extremes: the Vibro Meter 144-901-000-282 piezoelectric accelerometer. This charge-output accelerometer operates from -196°C to +700°C, so it survives conditions that destroy ordinary sensors. It meets NRC Guide 1.133 and IEEE 323-1974, and carries ATEX certification for Zones 0, 1, and 2. When you need spares when you need them, Oil AutoTech ships this unit fast, worldwide.
Technical Specifications That Matter
| Parameter | Value |
|---|---|
| Sensitivity (at 120 Hz) | 10 pC/g ±5% |
| Dynamic measuring range | 0.001 g to 200 g peak |
| Overload capacity | Up to 500 g peak |
| Frequency response | 3 to 2800 Hz nominal ±5% |
| Resonance frequency (mounted) | > 17 kHz nominal |
| Temperature range (continuous) | -54°C to +650°C |
| Temperature range (extreme) | -196°C to +700°C |
| Pressure rating | 140 bar at 23°C, 80 bar at 300°C |
| Internal insulation resistance | Min. 109 Ω |
| Mounting | 4 Allen screws M6, torque 15 Nm |
| Output | 2-pole system insulated from casing |
Sensitivity of 10 pC/g means the sensor generates a charge proportional to vibration. The charge converter processes this signal. With no input power required, the 144-901-000-282 works passively, reducing wiring complexity. The Inconel 600 hermetically welded case resists corrosion and humidity. Radiation tolerance is proven: gamma flux at 1011 erg/g and neutron flux at 1018 n/cm2 cause no effect.
Where This Accelerometer Performs
Nuclear reactor internals. Loose part monitoring demands a sensor that survives high radiation and temperature. The 144-901-000-282 meets NRC Guide 1.133 and IEEE 323-1974, making it a direct replacement for aging sensors in safety-related systems.
Steam turbine monitoring. Continuous operation from -54°C to +650°C covers turbine casing measurements. The 140 bar pressure rating at 23°C handles high-pressure steam environments.
Explosive atmospheres. ATEX certification LCIE 08 ATEX 6017 X II 1 G allows use in Zones 0, 1, and 2. This suits oil and gas facilities where standard accelerometers cannot go.
Installation and Integration Notes
Mount the sensor inside a tube using four M6 Allen screws. Tighten to 15 Nm. The 2-pole system remains insulated from the casing, so you avoid ground loops. Connect the Lemo connector to a charge converter; the cable length is 3.5 m. For fieldbus networks, wiring may require an external gateway or connection module. Confirm cables and gateways with Oil AutoTech before ordering.
Maintenance for Long-Term Reliability
Inspect mounting torque periodically. Check cable insulation for wear. Because the sensor has no moving parts and no input power, wear points are minimal. In high-radiation areas, follow your plant’s safety manual for inspection intervals. The Inconel 600 housing resists corrosion, but visual checks for physical damage remain practical.
Selection Checklist
Before buying, verify your charge converter accepts 10 pC/g sensitivity. Confirm the operating temperature range covers your application. Check that the Lemo connector matches your existing cabling. The 144-901-000-282 is a direct replacement for Type CA 901 standard versions. Please verify current lifecycle status and availability with Oil AutoTech before ordering.
Frequently Asked Questions
Q: What makes the 144-901-000-282 suitable for nuclear applications?
A: It meets NRC Guide 1.133 and IEEE 323-1974, and tolerates gamma flux at 1011 erg/g and neutron flux at 1018 n/cm2 with no effect.
Q: Does this accelerometer require external power?
A: No. Input power requirements are none. It uses a charge output with a 2-pole system insulated from the casing.
Q: What is the maximum temperature for continuous operation?
A: Continuous range is -54°C to +650°C. Extreme capability extends to -196°C to +700°C.
Q: Can I use it in explosive atmospheres?
A: Yes. It holds EC type examination certificate LCIE 08 ATEX 6017 X II 1 G for Zones 0, 1, and 2.
Q: What cable length comes with the standard version?
A: The ordering number 144-901-000-282 includes a 3.5 m cable with a Lemo connector.
