NI PCI-6071E current measurement

[clarabella]

I am trying to measure the power consumption for a coreless motor, so it will be hard to calculate the current by v/r. Is it possible to measure the current from DAQ with LABVIEW? I figured that PCI6071E can only read the current up to 40mA; however, the motor current could go up to 300mA, does it have any other possible ways to record the current changes in real-time?!

your help is highly appreciated!!!

[Corby_B]

Hello clarabella!

Thanks for your post!

I would like to start this out by saying current cannot be measured directly using the analog input of most DAQ boards. We do have some that are specifically designed for current such as the NI-6259.

So the 6071E has many analog input channels that are specified for reading voltages. So to translate this into current you could read the current from another sensor that translates this into a voltage then relate that to current in software. Another good point that you mentioned is that you will have a current that is very high and should not be directly connected to the DAQ board.

In your case your current may be low enough that the link above may be a bit overkill for your application. So there is another way you can do this using your own resistors and calculations depending on your load. You can use a known resistance value with an unknown load and relate that to current by reading a voltage. Take a look at the link below.

Measuring Current Using the Analog Input of a DAQ Board

Let us know if this helps you on your application and I wish you the best of luck!

Cheers!

Corby_B