High Voltage Switch Matrix?

[jplotzke]

Hi all,

I'm setting up a system where I need to do various DMM measurements on a set of test points of a UUT.  I'm looking at having a PXI 64x4 (1-wire) switch matrix and a PXI DMM in order to be able to switch in any of the incoming signals to a DMM channel.  However, I need to be able to measure up to 300VDC.

Of course the DMM can handle this, but I can't find any switch matrices that can.  I'm looking at the PXI-2533 which would be OK on the 64x4 site, but it only good to 50V.

I'm sure there must be others that use a switch matrix with a DMM -- Does anyone do it at higher than 50V?

Thanks for any suggestions you have!

Jeff

[Jason_D]

Jeff,

What is the minimum matrix size you are looking for?  We do have Mux switches that can do high voltage (2527/2584).  Unfortunately we do not have any matrix switches like this.

[Miikka]

Hi, I have a similar issue. I would need a switch that would have a high isolation between channels, at least 500V, but 1kV would be the good.

My case is that I need 24 isolated termocoupler measurements for CSA tests, and the isolation level would need to be arround 750V between channels.

Does anyone have any good solutions how to do this type of measurement setup? 

[rocketman 633]

Ufortunately there is no 300V, PXI matrix at this time.  Is it possbe for you to use SCXI?  The SCXI-1127 can be used as a matrix and is speced up to 300V.

Jim

[Miikka]

Well, there's no limitations on the hardware, so what ever works for this would be good. I have to look up that SCXI spec to see what it looks like.

I got one interesting suggestion to use NI WSN-3212 wireless sensor network to get the high isolation level between channels. So it would mean one module/channel, but I have to see would that work in real life.

[MaxXx]

Hello,

I'm also looking for a high voltage switch that can handle 2000V and be programmable with Labview. I have thought of using voltage dividers that can route through multiple switches but I'm not sure if it will work and it might also be a fairly expensive setup.

Message Edited by MaxXx on 10-07-2009 08:57 PM

[chericks1]

Hi MaxXx,

We don't have a PXI or SCXI switch module that can do 2000 V.  Have you considered the relay driver modules (NI PXI-2567 or NI SCXI-1167)?  They would allow you programmatically control 3rd party high-voltage relays using LabVIEW, and can provide up to 50 VDC / 600 mA per channel with an external supply.  The NI PXI-2567 module can provide 5 or 12 VDC (1.25 and 0.5 A, respectively) from the PXI backplane (no external supply needed), and the NI SCXI-1167 can provide 5 VDC at 0.75 A from the SCXI backplane.

Here's a link to the product pages:

NI PXI-2567: https://www.ni.com/en-us/shop/model/pxi-2567.html

NI SCXI-1167: https://www.ni.com/en-us/support/model.scxi-1167.html

Hope this helps!

Chad Erickson

Switch Product Support Engineer

NI - USA

Message Edited by Chad PSE on 10-07-2009 09:29 PM

[MaxXx]

Thank you for the suggestion, that was very helpful. I might go with a setup like this. I just have some questions though. Would I still need a separate switch module like the PXI-2586 or will this does everything by itself? (ie. I only need to connect HV relay switches and program the driver). Any other modules I might need? You say it can provide 5 or 12V, is this for each channel or all of them combined? (is it capable of switching 2 or more relays at the same time?)

Thank you.

Message Edited by MaxXx on 10-13-2009 09:07 AM

[chericks1]

Hi MaxXx,

You would only need to connect HV relays and program the driver to close the NI xx67 switches.  Once the hardware setup is configured as shown in the following picture (for a single-coil relay), closing an NI xx67 switch will source the required voltage and current to close a HV relay, and opening an NI xx67 switch will cease the flow of current and enable the opening of the HV relays.

From NI Switches Help: 

More informaton on the 5 V and 12 V internal sources of the NI xx67 is also available in the NI Switches Help: 

The sources are shared for the entire module, but can be used in conjunction with each channel.  Therefore, there may be a maximum number of relays you can control at once, depending on the required drive currents. 

The NI xx67 is capable of switching 2 or more relays at the same time.  The niSwitch Relay Control VI or the niSwitch_RelayControl function can be used: simply input the relay names separated by a comma.

Hope this helps!

Chad Erickson

Switch Product Support Engineer

NI - USA

[MaxXx]

Hello

Thanks alot for helping, I will purchase this setup. Just some more questions though, how would I connect cables to the PXI-2567 module? I read the manual and it doesnt seem to include any 78pin Dsub. Would I need to buy a separate 78pin dsub cable and a terminal block? and if so, which terminal blocks would be compatible? (I only see scxi terminal blocks not pxi/pxie)

Max