Floating voltage in BNC 2090, PCI 6024E

Hi experts, I have a single ended connection on a BNC 2090 connected to PCI 6024E board. However, when I leave it connected(without any input) I see that the voltage gradually increases to +10V. Even when I input a signal, I see that the 10V forms a baseline, which hinders any measurement. Is this some sort of grounding problem? Kindly post any helpful thoughts on this matter. thanks. Roshan.

Roshan,
I believe that the 2090 has a switch for each channel which configures the inputs for either Single Ended configuration (AI channel is read with respect to your 6024's Analog Input Ground) or Differnetial configuration (AI channel reads signal on BNC connector differentially). Ensure that the terminal configuration you have programmed for you channel matches the terminal configuration selected by the switch on the 2090. If you do not make any explicit setting, the 6024 will default to differential mode.
I hope this helps,
Dan

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Strange voltage observed in NI BNC 2090

Hi all, I have a BNC 2090 and AT-MIO-16O-2 DAQ board. I am recently
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This is actually very common. When nothing is connected to the pins the voltage will charge up on the leads. Sense the lines are not connected to anything and the voltage has no where to go the lines will normally completely saturate the capacitors on the board.
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http://digital.ni.com/public.nsf/websearch/DF70FCE03D397BFE86256A3700780FFA?OpenDocument
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Attachments:
ttl.vi ‏26 KB

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We handle all repair requests over the phone. The procedure is as follows:
1. Go to www.ni.com/ask to create your own Service Request number (SR#). Choose the Phone NI option. Fill in the form with the appropriate information.
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How does the system Validyne pressure transducer -- Validyne CD280-Dual-- SCB-68-- PCI-6024E-- LABVIEW work and how can we calibrate the pressure transducer?

Hello there,
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Experiment.vi ‏143 KB
Plogger.vi ‏21 KB

Hello there,
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Attachments:
Pressure plot.jpg ‏111 KB

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http://www.ni.com/support

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Dear Friends,
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AI_Start-Stop_D-Trig.zip ‏25 KB

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Thanks,
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... And here's where I keep assorted lengths of wires...

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Lcacho,
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“Engineers like to solve problems. If there are no problems handily available, they will create their own problems.”- Scott Adams

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One Step At A Time, Maybe Two...

200Ksamples/sec on a single channel, per the specs:
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"It’s the questions that drive us.”
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Floating voltage in BNC 2090, PCI 6024E

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