From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.
We appreciate your patience as we improve our online experience.
Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Mute
- Printer Friendly Page
charge acelerometers pC/g
Eng P&D
Member
02-24-2006 09:46 AM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
I would like to know if when working with charge acelerometers, there are some way to convert daq sinals.
Cause charge acelerometers work with sensitivity in pC/g and voltage with mV/g?
If not, what's the relation between both?
Thanks
Cause charge acelerometers work with sensitivity in pC/g and voltage with mV/g?
If not, what's the relation between both?
Thanks
Conseils
Active Participant
02-24-2006 05:01 PM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
The different scales relate to different types of output from accelerometer (or other) devices.
Specifically pC/g refers to a charge output that will normally require an amplifier to condition the signal. These types of transducers often have very low output signals but withstand higher temperatures and higher frequency ranges (a bit of generalising here). By using a charge amplifier a signal will be obtained which will be scaled by the pC/g factor to give an output in voltage (or current). These types of sensors of course suit battery powered equipment well.
mV/g refer to devices that have a voltage output but they require a constant current supply source (ICP {Integrated Circuit Piezoelectric a trademark of PCB} not necessarily identicle to IEPE sensors, consant current driven sensors introduced by Kistler in 1965 I believe) these types of devices are more suitable for noisy electrical environments and the signal can be driven over longer wires. The sensor contains an amplifier which is powered by the constant current supply which in turn produces a low impedance output as opposed to the high impedence output from the charge coupled types of sensors.
Either way you need to know what type of sensor you have and specify the correct input for the hardware of the DAQ system, then obtain the scaling to condition the signal correctly. More recently a system known as TEDS (Transducer Electronic Data Sheet) has been introduced to allow the transducer to hold calibration data and serial number information to simplfy the process of setting up instrumentation. Not all equipment or software supports TEDS but it is starting to appear.
You will find a really good article here if you want to go deeper into the subject.
http://www.pcb.com/techsupport/tech_signal.php
Specifically pC/g refers to a charge output that will normally require an amplifier to condition the signal. These types of transducers often have very low output signals but withstand higher temperatures and higher frequency ranges (a bit of generalising here). By using a charge amplifier a signal will be obtained which will be scaled by the pC/g factor to give an output in voltage (or current). These types of sensors of course suit battery powered equipment well.
mV/g refer to devices that have a voltage output but they require a constant current supply source (ICP {Integrated Circuit Piezoelectric a trademark of PCB} not necessarily identicle to IEPE sensors, consant current driven sensors introduced by Kistler in 1965 I believe) these types of devices are more suitable for noisy electrical environments and the signal can be driven over longer wires. The sensor contains an amplifier which is powered by the constant current supply which in turn produces a low impedance output as opposed to the high impedence output from the charge coupled types of sensors.
Either way you need to know what type of sensor you have and specify the correct input for the hardware of the DAQ system, then obtain the scaling to condition the signal correctly. More recently a system known as TEDS (Transducer Electronic Data Sheet) has been introduced to allow the transducer to hold calibration data and serial number information to simplfy the process of setting up instrumentation. Not all equipment or software supports TEDS but it is starting to appear.
You will find a really good article here if you want to go deeper into the subject.
http://www.pcb.com/techsupport/tech_signal.php
