Overview
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | 74712-06 |
| Brand | Bently Nevada |
| Product Type | Seismoprobe Velocity Transducer |
| Series | 9200 Series |
| Measurement Principle | Seismic velocity measurement |
| Measurement Reference | Absolute vibration relative to free space |
| Electrical Sensitivity | 20 mV/mm/s (500 mV/in/s), +/-5% |
| Frequency Response | 10 Hz to 1 kHz (600 to 60,000 cpm), +0/-3 dB typical |
| Dynamic Operating Range | 2.54 mm (0.100 in) peak-to-peak maximum displacement |
| Amplitude Linearity | +/-5% from 0.01 to 5.0 in/s (0.254 to 127 mm/s) at 100 Hz |
| Operating Temperature | -29 deg C to +204 deg C (-20 deg F to +400 deg F) |
| Storage Temperature | -29 deg C to +204 deg C (-20 deg F to +400 deg F) |
| Coil Resistance | 1.25 kOhm +/-5% |
| Shock Resistance | 50 g peak maximum acceleration along non-sensitive axes |
| Transverse Sensitivity | +/-10% maximum of sensitive-axis response |
| Height | Approx. 102 mm (4 in), typical |
| Diameter | Approx. 41 mm (1.6 in), typical |
| Weight | Approx. 480 g (17 oz), typical |
| Power Consumption | Not specified; the supplied data identifies the unit as a velocity transducer with a specified coil resistance |
| Environmental Resistance | Dust and moisture resistant |
| Typical Measurement Location | Bearing housings, machine casings, structural components |
Mechanical Vibration and Rotor Dynamics
The 74712-06 measures absolute vibration velocity rather than shaft-relative displacement. Its seismic sensing arrangement responds to casing or bearing-housing motion and produces an electrical signal proportional to vibration velocity.
The specified sensitivity is 20 mV/mm/s, equivalent to 500 mV/in/s, with a stated tolerance of +/-5% when properly terminated and oriented at the calibration angle. The 10 Hz to 1 kHz frequency response defines the stated measurement bandwidth.
For machinery monitoring, the transducer can provide casing vibration information used to evaluate mechanical behavior associated with rotating equipment. Installation orientation and termination should follow the applicable Bently Nevada installation and calibration requirements.
Frequently Asked Questions
Q: What type of vibration does the 74712-06 measure?
A: It measures absolute vibration relative to free space at bearing housings, machine casings, and structural components.
Q: What is the electrical sensitivity of the 74712-06?
A: The specified sensitivity is 20 mV/mm/s, equivalent to 500 mV/in/s, with a +/-5% tolerance under the stated calibration conditions.
Q: Can the 74712-06 operate at high temperature?
A: Yes. The supplied specification gives an operating temperature range from -29 deg C to +204 deg C.
Field Installation Guidelines
Install the transducer on a mechanically representative surface where casing or bearing-housing vibration can be transmitted to the seismic sensing element.
Maintain firm mechanical contact between the transducer and its mounting surface. Avoid mounting locations that introduce excessive structural resonance, loose mechanical coupling, or unrelated vibration sources.
Route the transducer cable separately from high-current power conductors and switching circuits where practical. Avoid sharp bends, mechanical abrasion, and locations subject to excessive heat beyond the specified temperature range.
Terminate the electrical connection according to the applicable monitoring-system input requirements. Verify the specified coil resistance and signal sensitivity during commissioning when test equipment and the monitoring system permit such checks.
Where shielded cabling is used, apply the site-approved instrumentation grounding practice. Avoid creating unintended ground loops through multiple shield termination points.
Confirm the installed orientation and calibration arrangement before accepting vibration readings. The supplied sensitivity specification assumes proper termination and orientation at the calibration angle.
Reviews
There are no reviews yet.