×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Converting dB to acceleration

Converting dB to acceleration

Converting dB to acceleration

(OP)
Hello
I recently measured vibration with a sound level meter (Norsonic 121 and accelerometer). The sound level meter only shows me values in dB. Can anyone tell my how I can convert the values to acceleration (or displacement)?
Thank you for your help.

RE: Converting dB to acceleration

You need to know the reference level of the dB calibration. Typically sensible people use 1g=0 dB, or 1 m s-2 = 0 dB.

Sadly there are many more standards than that.

Once you know this then
acceleration = Accref*10^((dB-dBref)/20)

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Converting dB to acceleration

The input amplifier specs for that meter list a range of .3 uV to 7 volts RMS.  The specs call this a dB range of -10 to +137.  Using this info I come up with a reference voltage level of approx .95 uVolts.  You'll need to find out what the volts/g's is for your accelerometer.  So for an example, if your accel puts out 1.9 uVolts at 1 g then the meter would show:

dB = 20 log (1.9E-06/.95E-06) = 6 dB

So an accel of 1 g would read 6 dB.

There appear also to be different gain ranges for the meter.  You'll need to take those into account also.

Make sure the electrical guys here check my numbers!!

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources