160-Pin Cable Pinout problem

[TreyB]

I have a PXI-2530B Mux with the 160 Pin cable. I am using a Dual 64x1 Topology and please correct me if this is incorrent but are the "OUT" channels, in the installation instructions, not the com ports? If so, I am having issues with the com ports. I have used the switch soft panel and connected a channel to com0 to check continuity with the module itself and it was good. When I connect the 160 pin cable to the module and check for continuity, with the same channel and com port (using the 50pin connectors), I get nothing. The reason I came to this is because I could not get a dmm reading from a simple closed circuit between two channels on each bank using the 160-pin cable. Please inform me if I am incorrect in my thinking or if there is anything else I need to take into consideration.

Thanks 

[Jeffrey_Zola]

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@TreyB wrote:

I have a PXI-2530B Mux with the 160 Pin cable. I am using a Dual 64x1 Topology and please correct me if this is incorrent but are the "OUT" channels, in the installation instructions, not the com ports? If so, I am having issues with the com ports. I have used the switch soft panel and connected a channel to com0 to check continuity with the module itself and it was good. When I connect the 160 pin cable to the module and check for continuity, with the same channel and com port (using the 50pin connectors), I get nothing. The reason I came to this is because I could not get a dmm reading from a simple closed circuit between two channels on each bank using the 160-pin cable. Please inform me if I am incorrect in my thinking or if there is anything else I need to take into consideration.

Thanks 

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Hi, Trey. I have several of the PXI-2530 switch modules, which are the same as your PXI-2530B except with a different front-panel connector. You didn't mention it, but should we assume you are using the 50-pin terminal blocks? I suggest that you check that you are using the correct one of the 4 "branches" of the 160-pin cable for the signals you are probing, as the first groups of signals counter-intuitively use the P2 and P3 branches of the cable.

I created the attached Excel file using the various manuals to help me set up various multiplexing topologies using my 2530's. It can be sorted by column to clarify where the signals are carried for the various topologies.

Jeff

[Now_With_Underscores]

Hey Trey,

When using the dual 64x1 topology, CH0:63 can connect to COM0 and CH64:127 can connect to COM4.

With that knowledge, if you connect COM0 to CH52, then front panel pin 141 is physically connected to pin 117.  Since you're using the LFH-160 cable, this means you've connected pin 1 of DSUB P3 (CH52) to pin 51 of DSUB P2 (Out0 (which is COM0)).  Let us know if you're not able to establish this connection. 

As always, until you're familiar with the topology, we strongly encourage using series current limiting resistors to prevent relay damage due to overcurrent during the design stage.  In many cases (voltage, 4-wire resistance, etc), the final design can continue using these current limiting resistors to limit inrush current.

[TreyB]

I was using a db50 breakout board for the 50-pin 'branches' until I noticed I was getting incorrect readings, or no readings at all. Yes I have the correct signals of what I am trying to measure. I have tried many and for the time being I am using com0 (P2 Pin 33) and ch0 (P2 Pin 1) to just check continuity to see if the cables are connected. I have used the switch soft panel to connect ch0->com0 and have tried measuring continuity with the end of the P2 branch with two wires sticking out and I get nothing. I have came to the conclusion that the lfh160 backshell is not seeding with the module connector. Reason is, when I use the P2 branch (Pin 33/Pin 1 again) and stick those in the correct ports in the module( 41 and 51) and measure continuity from the lfh160 backshell pins I get continuity. So it seems that the lfh160 backshell is not mating with the module connector to make a connection. I have tried tightening the screws on the backshell and far as they will go, removing the backshell and neither gets the job done. What I did notice is if I remove the while PXI-2530B piece on the front of the module with the fastener and then mate the backshell with the module the pieces seem flush together.

Thanks

[Now_With_Underscores]

Hey Trey,

Apologies, I listed the interface connector pin side of the cable, not the D-SUB side... ignore my previous post, I've posted the correct side of the cable below:

When using the dual 64x1 topology, CH0:63 can connect to COM0 and CH64:127 can connect to COM4.

With that knowledge, if you connect COM0 to CH52, then front panel pin 141 is physically connected to pin 117.  Since you're using the LFH-160 cable, this means you've connected pin 21 of DSUB P3 (CH52) to pin 33 of DSUB P2 (Out0 (which is COM0)).  Let us know if you're not able to establish this connection. 

As always, until you're familiar with the topology, we strongly encourage using series current limiting resistors to prevent relay damage due to overcurrent during the design stage.  In many cases (voltage, 4-wire resistance, etc), the final design can continue using these current limiting resistors to limit inrush current.

...
Let's remove the cable and use the independent topology to continue debugging.  In the soft front panel, close relay k0 (in the relay tab; you'll need to enable manual relay control in the SFP preferences).  Then see if pin 141 is connected to pin 133.

[Now_With_Underscores]

Another configuration to test is connecting relays relays k0 and k1, then see if there's a short between pins 133 and 89.

[TreyB]

Hi John,

I have done what you have mentioned also. Have connected switches in the soft panel to make sure the module is making the connection and it does. And have also been using the 2530B for many continuity measurements and for this I just used resistors and shorts in the module front panel itself, running through code and everything measured about great with the 4070 dmm from com0 and com4(using Dual 64x1).

Now that I am doing something different(but using the same module), which involves the lfh160 cable, I am having issues with what seems like the cable itself.

[TreyB]

I tried a few other solutions. Removed the white connector piece, with the fastener, on the module and connected the backshell that way and it failed. Removed the backshell piece itself and tried that and it failed.

I know the cable is good as I used P2 CH5(Pin 6) and OUT0(Pin 33) and set wires out of the P2 cable for continuity. Used the 160 pin backshell end to short Pin 51(com0) and Pin 38(Ch5) together and got continuity. Did the same with the module, 2530B, and closed the channel ch5->com0 in the soft panel and received continuity from the 2 wires in pin 51 and 38 in the module connector. So somehow the 160 pin backshell is not mating with the 2530B module when they are connected and I have tried many ways.

[NEWKlear]

Hey TreyB,

The best thing to do so we can better investigate this issue is to call in at 1-866-ASK-MYNI and create a service request so we can RMA and investigate the behavior further.

Have a great weekend!

[TreyB]

I have and it is being taken care of. Thank you