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thols
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Connect individual pin on 2-wire mux using NI-Switch

I have a 2-wire MUX (2576 with cable LFH160 and four terminal blocks TBX-50). I have from the TBX-50 connected each wire in a 2-wire-pair to an input on an RF-switch (2593). In Switch Executive (NISE), each 2-wire pair will be shown as a channel (ch1, ch2, ..., ch64). Is it possible to split these channels into each wire (ch1+, ch1-, ch2+, ch2-, ...) so I can create hardwires in NISE that represent the physical connection between a 2576 and a 2593?

 

In the properties for 2576 I can select Terminal Block TB-2676. I expected to be able to see each individual wire in NISE if I selected that I had this block, but I couldn't see that anything changed. The help file isn't very helpful here either. Or why else is it possible to select a Terminal Block. And why is it not possible to select TBX-50?

 

 

Member
EricS.
Posts: 179

Re: Connect individual pin on 2-wire mux using NI-Switch

Hi thols,

 

To answer your question, no, there is no way for NISE to know which individual wires of a 2-wire device are connected (if they are not connected to another 2-wire device).  However you can sitll create the hardwire between ch0 of the 2-wire device and com of the 1-wire device.  When NISE is configured for hardwires, it associated channels together, not individual wires.  You sill still see the superscript next to the channels in the schematic to know that the channels are part of a hardwire but NISE does not know which individual wires are connected.

 

More importantly, NISE cannot create a route between between a 2-wire device and a 1-wire device.  If you try to create a route on a 2-wire device (based on which channel you select first) the route configuration will only show 2-wire devices.  Similarly if you select a 1-wire channel first, NISE will only show other 1-wire channels as possible endpoints. You can of course create two routes, one for each wire-type, and create a route group that contains both routes.  This would create the full route for you when you call to connect the route group.

 

Even more importantly, why are you using a 2576 and 2593?

 

The 2593 is a 500 Mhz RF switch, and the 2576 has extremely low bandwidth coparitively.  All RF signals (including digital edges) will be dramatically attenuated in the 2576.  If you need to switch RF signal, you should be using all RF switch modules.  If you are not using RF, then the 2593 is overkill and you could easily use a different multiplexer.

 

 

 

For your last question, when you select the terminal block in MAX it will automatically limit the different topologies you can choose (note: independent mode is only avaialble without the terminal block).  For other modules the terminal block selection is different and often a terminal block supports only one topology.  Terminal blocks often make explicit connections on them to expand matrices or change multiplexer wire modes.  The TBX-50 does not do this, and is a simple pin-pin mapping that does not require a drop down in MAX.

Eric S.
AE Specialist | Global Support
National Instruments
Member
thols
Posts: 21
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Re: Connect individual pin on 2-wire mux using NI-Switch

Hi Eric,

Thanks for your answer. It will be of great help.

Using a route group will be a good enough solution. I kind of forgot to use route groups since my routes were so simple (until now). I guess I was carried away by the way the Visual Route Editor" in the "Routes/Groups" tab displayed the route, and hoped that I could see everything there.

Thanks for noting that the superscript next to the channels in the schematics is visible when creating a hardwire even between 2-wire/1-wire switches. I didn't think of that. I will use this.

Also, thanks for caring about my hardwire setup. I have a bunch of RF-signals and 8x 2593's. These signals will only go through 2593's. But I also have some signals with very low bandwidth requirements which I will mux in the 2576 and then route through one or two of the 2593's (to connect to the same instruments as the RF-signals). So we should be fine there.


Member
EricS.
Posts: 179
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Re: Connect individual pin on 2-wire mux using NI-Switch

Hi Thols,

 

I'm glad to hear my comments were able to help.  Also, thanks for clarifying about you use of both the 2529 and 2593.  That definitely makes sense and you shouldn't have a problem with it.  Good luck with getting everything up and running and if you have more questions let us know!

 

 

Eric S.
AE Specialist | Global Support
National Instruments