USB-6008

[Raman Jaiswal]

How to use Daq Vi like analog input,analog output with USB-6008

[Dennis_Knutson]

Up until recently, you had to use DAQmx base that shipped with the unit and the examples for that. Now, you can download DAQmx version 7.5 which has support for the USB-6008. Then you can use the DAQmx shipping examples in LabVIEW.

[Ronin]

About analog input I have the following question:

 I want to analyze the 220 V waveform using USB-6008 three analogic input (three phases) and I was thinking to use a 220V to 10V transformer in order to avoid any damage of the electronic board but because I want to display an armonics chart the transformer is a filter for high frecvency signals that may modulate the sinusoidal waveform the transformer will perform as a low frecvency filter pass. I was thinking to use a resistor devider but there is a high risk of deamaging my USB board and even the PC. How should I do it? I know that the sampling frecvency is very poor but I am looking forward to any help I can get.

Regards,  RoninMBV 

[RobtheVib]

I've been using an NI USB 6008 - driven by NIDAQmx version 8.3.1 -  with LabView 7.1 and have the following problems:

1. Channals Ai0 and Ai6 RSE do aquire signals but with totally wrong amplitude values. The other channels work perfectly and accurately;

2. The Analog outputs (Ai0 and Ai1) don't work with LaBView neither with SignalExpress Tektronix. Error 200077.

3. The PFIO (digital port for external trigger) seems not to be working.

Can anyone help me to sort this out?

Thanks in advance...

Roberto

[Sandra_T]

Hello RoninMBV,

It looks like in your application you want to measure and analyze a 220V signal with one of our USB DAQ devices. You are concerned with the high voltages and require the full spectrum of frequencies.

For such an application you need a way to step the voltage down to something in the range of your board. You have the option of building custom high-impedance voltage divider circuitry or to use a voltage transducer to lower the voltage.

Take a look at these previous discussion forum postings on this similar issue:

Measuring High Level Signals

High Voltage!

Another concern I have would be isolation. You want to consider additional external circuitry to deal with possible voltage spikes. I know that National Instruments has Isolated PCI solutions that provide physical isolation, for instance the PCI-6232 or consider a DMM solution like the PCI-4065 which has ±300 VDC/Vrms isolation.

I hope this was of help.

Regards,
 Sandra T.

Applications Engineer | National Instruments