Re: Data acquisition for ICP accelerometers

[Matt Rippa <mrippa@gemini.edu>]

Our accelerometers are also from PCB Piezotronics. We use
model#'s 333B50 and some triaxial 356B18. Their resolution goes
down to 50 ug so at some point I worry about the noise floor
with the less expensive DAQ units. Have you had any concerns
along these lines? I believe many sites are amplifying these
signals to overcome this. The turn key systems I referred to are
all significantly more expensive but the dynamic range is
upwards of 144 dB.

Josh, I'm certainly interested to learn more about your system.

Thanks for all the input.
-Matt


On 11/28/2012 06:22 AM, S. Stein wrote:
> As Mark pointed out, the APS has installed a few 3-axis
> accelerometer systems as a way of monitoring effects of large
> equipment near certain points of interest. These use Piezo
> transducers from a company named "PCB Piezotronics" coupled
> to an amplifier which - as Mark indicated - feed into an
> inexpensive USB ADC from Measurement Computing.
> 
> The system works under Windows currently due to the libraries
> which were supplied being Win32 based. We do have a student
> working on Linux drivers which have shown promise; enough
> that we hope our next installations will be under on a Linux
> OS.
> 
> I'll be happy to give you more info if this interests you,
> 
> --Josh
> 
> 
> ----- Original Message ----- From: "matthew pearson"
> <matthew.pearson@diamond.ac.uk> To: mrippa@gemini.edu,
> tech-talk@aps.anl.gov Sent: Wednesday, November 28, 2012
> 4:50:23 AM Subject: RE: Data acquisition for ICP
> accelerometers
> 
> Hi,
> 
> This probably doesn't meet your requirements, but thought I'd
> mention it...
> 
> On at least one beamline at DLS we have a few Bruel & Kjaer
> charge accelerometers mounted inside a UHV double crystal
> monochromator. We use their Nexus amplifier to read the
> signals and feed them into a 16-bit ADC, and we control the
> amplifier via RS232. Then we do a FFT on the amplifier
> waveform data. But we only have a few channels to deal with,
> and we don't actively monitor the data (just analyse it on a
> ah-hoc basis when we have time).
> 
> However, we've only just started to use them so we don't have
> much experience with them so far. I'm not sure which actual
> accelerometer we're using, but the manufacturer has a range
> of different types. We use them for looking for mechanical
> vibrations in the 1-100Hz range.
> 
> http://www.bksv.com/products/transducers/conditioning/charge/2692c.aspx?JsEnabled=0
>
>  Emma Shepherd developed the streams based Epics support for
> the amplifier.
> 
> 
> Cheers, Matt
> 
> 
>> -----Original Message----- From:
>> tech-talk-bounces@aps.anl.gov [mailto:tech-talk- 
>> bounces@aps.anl.gov] On Behalf Of Matt Rippa Sent: 28
>> November 2012 02:39 To: tech-talk@aps.anl.gov Subject: Data
>> acquisition for ICP accelerometers
>> 
>> Hi,
>> 
>> Has anyone worked with vibration monitoring and analysis
>> in EPICS? We're looking for a digitizing system with 24 or
>> more channels and dynamic range of 96 dB or higher. Our
>> sensors are ICP accelerometers with resolution down to 50
>> ug's (uV) and sensitivity of 1V/g.
>> 
>> It seems there are plenty of 'turn-key' systems out there
>> with Windows only. For example, this is a good fit but no
>> linux/epics.
>> 
>> http://www.spectraldynamics.com/index.php/products/puma
>> 
>> Thanks, -Matt
> 
>