Measuring small voltages

[dafemagu]

Hi there,

I would like to implement to measure very small voltage.  So, I need to measure voltage in the order of 0.5 mV and 5mV (the current of the system will be in the order of the 5A to 50 A) , with a resolution of 0.05 μV to 0.5 μV. Is there any national instrument  euipment that can help me to do this?, Alternatively, I will work with a nanovoltmeter model 2182A. However, I am in the same situation, because, I want to register the data in my computer using a ni usb 6009 (In theory, this equipment does not have enough resolution), Maybe, I need an amplifier in the middle. Please, Could you suggest me a DAQ for doing this job?

Regards.

[Hatef.fouladi]

you have to use 24 bit daq for full ADC
also check about signal conditioner and amplifier to make full range measurement

[crossrulz · Accepted solution]

There are special amplifiers specifically for current shunts, for example the TSC103IPT.  This one has three different gains.  The setup I'm going to use for a test system soon will be a .05 Ohm resistor and this amplifier set up to have a gain of 20.  With that setup, I have a 1V at the DAQ is 1A.  From there, your 6009 should have plenty of resolution for you.