Description
The Bently Nevada 190501-12-00-05 is a low-frequency, piezoelectric integrating velocity sensor designed specifically for machinery condition monitoring in harsh environments. It measures casing vibration velocity on slow-speed rotating machinery, primarily cooling tower fans and air-cooled heat exchanger fan assemblies that operate at or above 90 rpm (typically 100 to 300 rpm). By incorporating internal integration electronics, this sensor converts a raw acceleration signal into an industry-standard velocity output, allowing direct routing into machinery protection systems such as the Bently Nevada 3500 series.
Commercial Availability & Terms
- Condition: New Original (Factory Sealed Surplus)
- Warranty: 12-Month Comprehensive Industrial Warranty
- Availability: In Stock
- Standard Lead Time: Ships within 1–2 business days via global express couriers
- Pricing Note: Price is subject to regional market conditions and component allocations. Contact our technical sales engineering division for a firm, formal quote.
Part Number Configuration Breakdown
The alphanumeric structure 190501-12-00-05 defines the specific mechanical mounting interface, termination layout, and global regulatory compliance envelope for this asset:
- 190501 (Base Model): Velomitor CT (Cooling Tower) low-frequency piezo-velocity sensor platform.
- -12 (Mounting Hardware): Includes a Plate Stud adapter scaling from 3/8-in 24 UNF to an M8 × 1 metric thread.
- -00 (Connection Option): Standard top-mounted 2-pin MIL-C-5015 stainless steel receptacle.
- -05 (Agency Approval): Multiple International Agency Approvals package (combining CSA, ATEX, and IECEx certifications for safe deployment in Zone 0/1 and Class I, Division 1 hazardous locations).
Technical Specifications
| Parameter | Value / Specification |
| Sensitivity | 3.94 mV/mm/s (100 mV/in/s) \pm5\% calibrated at 100 Hz |
| Frequency Response (\pm1.0 dB) | 3.0 Hz to 900 Hz (180 to 54,000 cpm) |
| Frequency Response (\pm3.0 dB) | 1.5 Hz to 1.0 kHz (90 to 60,000 cpm) |
| Velocity Range | 63.5 mm/s peak (2.5 in/s peak) maximum dynamic limit |
| Output Bias Voltage | 10.1 V DC \pm1.0 V DC (Pin A referenced to Pin B) |
| Excitation Voltage Requirements | Constant current source of 2 to 10 mA over a voltage range of -10 to -30 V DC |
| Case Material | Hermetically sealed 316L stainless steel |
| Operating Temperature | −40 to +85 °C (−40 to +185 °F) continuous operational range |
| Mounting Torque | 4.5 N\cdotm \pm0.6 N\cdotm (40 in\cdotlbf \pm5 in\cdotlbf) |
Field Integration & Architectural Constraints
When deploying the Velomitor CT on structural fan cowlings or gear reducers, observe these rigid mechanical constraints:
- Low-Frequency Noise Floor Floor: Because this sensor is tuned down to 1.5 Hz, it is sensitive to thermal transients and base strain. Ensure that the sensor base is completely flush against the mounting flat to mitigate false low-frequency “vibration spikes” generated by mechanical casing distortion.
- Cabling Constraints: Utilize high-quality twisted, shielded pairs (such as the Bently Nevada CB2W100 series with a yellow Teflon jacket). Cable runs can extend up to 305 meters (1,000 feet) to the monitor rack without signal degradation, provided the total capacitance does not exceed 200 pF/m. Ground the shield purely at the monitor rack terminal block; isolate the shield at the sensor housing.
- Orientation Freedom: The 190501 can be mounted in any spatial orientation (vertical, horizontal, or inverted). However, when tracking unbalance on low-speed fan blades, the sensor must be positioned perpendicular to the shaft axis on the bearing housing for accurate radial velocity tracking.
Frequently Asked Questions
What differentiates the 190501 Velomitor CT from a standard 330500 Velomitor?
The 330500 standard Velomitor is optimized for general-purpose rotating machinery and has a low-frequency cutoff around 4.5 Hz. The 190501 Velomitor CT shifts the internal electronics filter downward, extending the usable frequency range down to 1.5 Hz (\pm3.0 dB). This allows the CT version to accurately capture structural defects on ultra-slow shafts turning at speeds as low as 90 rpm.
Can this sensor be used in areas with constant moisture condensation?
Yes. The housing is constructed from corrosion-resistant 316L stainless steel and is hermetically sealed. For cooling tower cells where 100% condensing humidity or chemical water treatment mist is present, you must use a splash-proof boot assembly over the 2-pin MIL-C-5015 connector to prevent moisture from bridging the electrical contacts.
How do I verify if the sensor element has failed internally?
Disconnect the field cable from the monitor rack and measure the DC bias voltage across the signal lines using a standard digital multimeter. Under normal operating conditions, the bias voltage should sit steady between 9.1 V DC and 11.1 V DC. A reading approaching 0 V DC indicates an internal short circuit or cable grounding failure, while a reading locked at the supply rail voltage indicates an open-circuit fault.
