Home » Bently Nevada Vibration Probes Functional Testing
Calibration Guest Articles Vibration Measurement

Bently Nevada Vibration Probes Functional Testing

Bently Nevada Vibration Probes Functional Testing

Objective :

To check the characteristics and healthiness of vibration probes ( make : Bently Nevada )

Principle:

Proximity transducers use Eddy Current principle to measure the distance between the probe Tip and the surface to be observed.

The proximeter generate a low power radio frequency (RF) signal. This RF signal is connected to a coil of wire inside the probe tip by the extension cable. When No conductive material is within the range of RF signal which surrounds the probe tip, virtually all of the power released to the surrounding area is returned to the probe. When a conductive surface approaches the probe tip, the RF signal sets up small eddy currents on the surface. These eddy currents creates a measurable power loss in the RF signal. When vibration tip nearer the target the greater the power loss. The system uses this power loss to generate as output voltage.

The output voltage of the proximeter is linearly proportional to gap over a wide range.

Required tools:

  • Multimeter
  • TK-3

Also Read : What is TK-3

Equipment Setup:

To check the characteristic of vibration probe

Procedure: Follow the following steps

1) Physically check the vibration probe and extension cable for any damages, if it is please Replace with new one.

2) Check resistance of vibration probe and continuity of extension cable it should be in between 5 To 9Ω and 5 to 20 Ω (resistance value varies from model to model)

3) Place the vibration probe on TK-3 spindle and adjust to the target plate surface and make sure the scale should be zero.

4) Connect multimeter on proximeter common and Vout terminals. Apply input voltage.

5) Measure the output voltage (multimeter reading) and increase the target distance in the TK-3 calibrator and follow the same steps as per given table and note down the output voltages at different displacements (gaps).

Bently Nevda Vibration Probes Voltage

6) After this make a graph which shows the relation between gap and voltage.

7) If graph is linear in between 10 mils to 80 mils then probe is in good condition.

Vibration Probe Calibration

Proximitor Calibration graph :

Bently Nevda Vibration Probes Calibration

Note : Change in gap is within 80 mils Linear Range which is in between 10 mils and 90 mils

Article by :
Ashish Agrawal

Similar Articles:

Related Articles

RTD Calibration

S Bharadwaj Reddy

Level Transmitter Calibration Procedure

S Bharadwaj Reddy

Calibration of Gas Detectors

S Bharadwaj Reddy

Abbreviations of Pressure, Temperature & Flow

S Bharadwaj Reddy

Types of Level Gauges

S Bharadwaj Reddy

Practical Calibration Standards

S Bharadwaj Reddy

7 comments

rakhi rawat October 21, 2017 at 8:38 am

its a very good n easy for learn i like too much this article

Reply
prasanth October 26, 2017 at 3:42 pm

Why using negative voltage? -24vdc

Reply
S Bharadwaj Reddy October 26, 2017 at 3:45 pm

Hi, check this article, CLICK HERE

Reply
azetou October 31, 2017 at 2:16 pm

Thank you for the article, there is a mistake in the graph though : Gap is in mils not in millimeters.

Reply
S Bharadwaj Reddy October 31, 2017 at 3:44 pm

Corrected. Thanks for your efforts & updates.

Reply
ashraf April 15, 2018 at 11:40 pm

Incremental Scale Factor (ISF) is just as important as Average Scale Factor (ASF). For a better proximity transducer system verification, one can easily refer to Bently Manuals. They have written the procedure in a clear and concise manner.

Another important thing, need to confirm machinery shaft material as well whether the proximitor used is modified for linearity other than AISI 4140 (typical material for shaft). You can see physically a ‘MOD’ sticker with details on it, on the side of the proximitor itself. Performing a verification check using a MOD proximitor against a standard AISI 4140 spindle micrometer will render the result invalid.

Reply
Breaker November 13, 2018 at 4:04 pm

i couldn’t find the manual from bently nevada that talks about the procedure for checking or calibration te sensor*proximiter , could you please refere to this document or give me the link to it thanks

Reply

Leave a Comment

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More

WordPress Image Lightbox