Looking For Recommendations On Logger


Kchristensen

Recommended Posts

I'm looking for some recommendations on how to go about taking measurements of current between a microelectronic device and its battery. The device has been experiencing some issues regarding projected longevity of the battery and the actual field reports I'm getting back of actual longevity. While I think I've found the source of the issue and fixed it I need to fully verify that nothing is happening that's unexpected. I have a test setup that incorporates an electronic shunt that converts any current measurement into voltage that I can then look at under an oscilloscope. The problem is that while the oscilloscope provides a very accurate picture of time slices of pulses that are of interest I want to be able to record the behavior of the device over a period of time of 2-4 hours. I need to log the voltage data at a 10kHz rate and that creates a rather large data set on top of requiring some sort of hardware piece that can record at that rate. I'm completely unfamiliar with this sort of data acquisition and I'm looking for ideas on how to go about this sort of testing with some specifics towards hardware and software tools I can use.

Link to comment
Share on other sites

My recommendation is a LabJack for hardware and of course DAQFactory for software.  LabJack's are affordable, easy to use, and very flexible.  I'll have the folks at LabJack recommend which unit you would want.  It will largely depend on desired resolution (precision) that you need.

Link to comment
Share on other sites

My recommendation is a LabJack for hardware and of course DAQFactory for software.  LabJack's are affordable, easy to use, and very flexible.  I'll have the folks at LabJack recommend which unit you would want.  It will largely depend on desired resolution (precision) that you need.

 

Thanks. I'm down in the 10mV - 20mV range for detection of the current I want to measure.

Link to comment
Share on other sites

If you want to resolve a 0-20mV signal with good resolution, then you want a U6/T7, or even better the -Pro version of either.  There are many differences between the U6 & T7, but the main difference is that the U6 is usb-only, whereas the T7 is USB + Ethernet (also +WiFi on the -Pro):

 

http://labjack.com/u6

http://labjack.com/t7

 

What is the resistance of your shunt?  What is the voltage on either side of the shunt versus ground?

Link to comment
Share on other sites

Variable

in the nA range the resistor is a 10k, 0.1%

in the uA range the 10k is put in parallel with a 10R 0.1%

in the mA range it's a 10mR 0.5%, with a switch contact resistance of 70 millohms that factors into the total shunt resistance

 

I'm uncertain as to the voltage on either side of the shunt. Since it's a variable shunt and there are other elements in the circuit I'd have to do some investigation to figure out what those values might be.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.