Measure 36kHz ~60Vpp signal by PXI.

[Bill Choy]

Hi,
 
I have a reomte monitoring system running with PXI RT controller and some DAQ cards. I would like to measure a 36kHz ~60Vpp signal but DAQ card is not suitable to measure such high voltage. Are there any suggestions about that? I prefer to use 4-20mA output transducer but I didn't find suitable one until now.
 
Thanks,
Bill Choy

[Tiptop]

Let's see.

We have several cDAQ/cRIO boards that support higher voltages, like 60 volts.  However, DAQmx is only supported using the USB interface, which is not support on LabVIEW RT.

If you must have RT, then I would take a look at an SCXI system.  You can get a combo chassis that will be both PXI and SCXI, giving you the ability to measure higher voltage signals.

Another option is to move from daq to cRIO.  A cRIO chassis runs LabVIEW RT, and has higher voltage modules.

Lastly, I would give NI a call if you want to explorer the options.  They know all of the solutions better then I do, it's there job.  🙂

-Justin

P.S. all of this assumes that you weren't looking to build signal conditioning on your own.

[BrowningG]

Hello Bill,

Thanks for contacting National Instruments.

Justin has made some excellent suggestions to get you started with signal conditioning using real-time.  SCXI and SCC both offer signal conditioning solutions compatible with real time that would add on to your existing setup.  CompactRIO would require the purchase of additional hardware, but if offers small size and multiple options for signal conditioning built into compatible modules. 

If you are looking to purchase any items from NI, it would be best to contact them directly.  The technical representatives and applications engineers will be able to help you find the best solution with regards to your current setup and application needs. 

Please post back if you have any questions or concerns. 

[Bill Choy]

Hi Browning,

My existing system is PXI running RT platform. If there are any other products support RT and able to measure 36kHz ~60Vpp signal. Please give me the model number.

Thanks,

Bill Choy

[BrowningG]

Hello Bill,

Both the PXI 4070 and PXI 4072 DMMs are capable of high voltage waveform acquisition.  Their drivers are compatible with LabVIEW Real Time as well. 

If you are interested in purchasing one of these, I would recommend contacting NI directly to ensure that these devices will fit your needs. 

Please post back if you have any questions or concerns. 

[Bill Choy]

Hi Browning,

Actually I used 4070 to measure this signal before. However, I have to measure many test points with this signal now so I can't use 4070 because the cost is too expensive and occupy too many PXI slots.

Thanks,

Bill

[BrowningG]

Hello Bill,

If you are able to switch platforms, using CompactRIO with the NI 9221 will allow you to make a high voltage measurement at the 36 kHz. 

If you are able to test each of the test points one at a time, there are several PXI switch modules available.  If you go to the switches webpage, you can browse through all of the options by categories.  These browse options allow for you to narrow the switch down by OS Support, Bus Type, and Maximum Voltage.  A switch would allow for you to test multiple test points without the need for multiple digital multimeters or the need to change the wiring. 

Please post back if you have any questions or concerns.