selection of DMM

[VZn]

Greetings. I have six Kikusui power supplies PAN35-20, which has the output voltage 0-35V and current 0-20A. I want to use PC to read the exact output voltage and current.

What I am thinking now is maybe I need a mutichannel Digital multimeter to measure all these six power supplies simultaneously. The accuracy I need is only 0.1V and 0.1A.

Any suggestions for DMM choosing? Thank you.

VZn 

[Jarrod_B.]

Hello VZn,

In order to measure multiple channels with a DMM, you would have to use switches to connect each of your DUT's to the single DMM input channel.  For more information on possible switch configurations to use with a DMM, please refer to Common Switch Configurations for NI Modular Instruments.

In terms of your current requirement, the NI PXI-4071 has the highest current range out of all DMM's that we offer at 3 A.  You can measure higher currents by using an external precision shunt, but the highest current shunt we sell is the CSM-10A, which can handle currents up to 10 A.  In order to measure a current as high as 20 A, you would have to find a third-party current shunt and wire up your own circuit to perform a voltage measurement on this shunt. 

I hope this helps!

Best regards,

[dataforth]

Hi,

have you considered just reading back the info from each power supply through its gpib part? unless you consider the response to be possibly inaccurate it should do the job.

[the_intern]

I was wondering what is the best DMM that has PCI slot/bus for measuring voltages (o - 64V) and currents up to 2-3 A ? Are all DMMs have only one channel?

[the_intern]

I don't see any Switch cards that support PCI bus. Am I right?

[Sandra_T]

Hello the_intern,

In terms of DMM PCI solutions we have the PCI-4065 that will both your specifications. Take a look at the following references to learn more about the product:

NI PCI-4065 Low Cost 61/2 Digit DMM for PCI

With regards to your other question about switches refer to this discussion forum posting.

Regards,
  Sandra T.

Applications Engineer | National Instruments

[kawaiicat]

How about i want to measure differential output. I got an differential signal. the amplitude of it is 0-80V around. So the peak to peak with be -80V- 80V. I wonder if i can use PCI-4070 to do so but how should be the configure?

[Sandra_T]

Hello Kawaiicat,

The PCI-4070 is rated with a maximum voltage measurement range of -300V-300V. You will not have any issue making a +/-80V measurement. Take a look at the detailed specification for the 4070 family of DMMs for more information.

Regards,
  Sandra T.

Applications Engineer | National Instruments

[kawaiicat]

Thanks  Sandra T

I've look at that product spec. Actually I just afraid the "LO" is connected to GND so i can't put that 2 signals as they are differential. But i check the port drawing.. i guess the 2 ports  are floating and with respect to ground, am i right?

Between, I am getting familiar with the Labview. As i am going to use the generator to generate signal and the system i am going to test will output a 120-180V peak to peak signal.
I got a PCI 5911 but i know it is not going to work, that's why i want to find another DMM for that application.

However, when i try to use the DAQ assistant, i can't find any port whatever analog in or analog out . Is that because PCI 5911 is not DAQmx series? Do u know if the 4070 is in DAQmx series? any link can show what's card is supported by the DAQmx ?

[Sandra_T]

Hello Kawaiicat,

Yes the two leads are making differential measurements and are isolated.

I see that you are using the PCI-5911 , you need the NI-SCOPE driver to program this part. You can download the driver here.
If you have additional question about programming or about the hardware post your questions here.

With regards to programming the DMM in LabVIEW you use the NI-DMM software. You can download this driver here.

These modular instruments usually have its own soft front panel software that installs with the driver. You can use this utility to quickly test your hardware.
For example for how to use program the DMM in LabVIEW take a look at the shipping examples. After you have installed the driver, in LabVIEW, click on Help>>Find Examples. In the Browse tab, select Hardware Input and Output>>Modular Instruments>>NI-DMM for a list of examples.

Happy programming!!

Regards,
  Sandra T.

Applications Engineer | National Instruments