buying a usb digital multimeter for labview

[acgraham]

hey guys, im a total newb to this program but im already hooked.  i've made a multimeter interface out of a voltage regulator and the k8055 velleman kit.  but i think id like some better accuracy.  are there any affordable digital multimeters with two inputs that interface with labview via usb?

I figured it would be good to get recomendations here.

[kirsch]

National Instruments makes a very, very nice bus-powered USB DMM that can be used from LabVIEW through the NI-DMM API: The NI USB-4065.

http://sine.ni.com/nips/cds/view/p/lang/en/nid/204061

This is a really nice, high precision and high performance DMM:  6.5 digits of resolution and 7 kinds of measurements.

Marcos 

[chuggins143 · Accepted solution]

Might take a look at...

http://www.mccdaq.com/products/usb_products.asp

They don't have a stand alone DMM but there may be something there you could use for way less than the $1300 NI wants for their DMM unit.  I'm running a bunch of MCC equipment with great results!  ...MCC is a subsidiary of NI if that helps.  🙂

[kris.c1986]

Hi, 

     My question is also along the same lines. I posted the question by mistake in the LABVIEW forum last night.  I feel this is a more relevant place to be asking about how the NI USB-4065 meter should be used. 

     I have a 4-node Intel Nehalem cluster which draws power through a power strip. I am using a wire-splitter like this one : http://www.multimeterwarehouse.com/M920f.htm and a lower resolution clamp meter (http://www.amazon.com/Mastech-MS2205-Digital-Clamp-Interface/dp/B002VZA7L4) to measure the total power drawn by the entire cluster. It has a very low sampling rate and generates one reading per 0.7s. I would like to upgrade to something like the NI USB-4065 as it seems to have a significantly higher resolution.  

     My question is, can I use something like the NI USB-4065 to measure power consumed by the cluster by using the wire-splitter and the probes? Or will I have to splice the power cable to measure the overall power that is being drawn by the cluster? 

Thanks

[GarPar]

Kris-

     As long as you have a probe that outputs either the current or the voltage, you can use the 4065 for your measurements without splicing any cables.  One thing to keep in mind, however, is that the USB-4065 does not measure power.  It only measures current or voltage.  If you need real-time power measurements, you will need two DMMs: one to read the instantaneous current and the other to read the instantaneous voltage.  Then, Power = Current (Amps) X Voltage (Volts).

     Best of luck with your application!

[kris.c1986]

Gary,

         Thanks for the explanation.