PXI-4351 reading rate

Hello,
I'm using a 4351 board for RTD and thermocouple measurements. I've got a strange behaviour when activating "auto-zero at start" : the reading rate is higher than with no auto-zero at all. It looks like it was in "Fast" mode, although i leave the reading rate in "Slow" mode.
I'm using a pxi controler with labview RT 8.2.1 and 435x driver 2.5.2.
Any help would be very appreciated
regards
Ludos

Hello,
Thank for your answer.
In fact, the acquisition in "Slow" mode is not too slow, it just match the spec (p 2-4 of the NI 435x User Manual), witch is given with no auto-zero : 2.8 readings per second, to be divided by the number of channels.
With 5 chanel (+ 1 for CJC), the acquisition take approximately 2.15s in slow mode, no autozero => 2.8 readings/s
Activating Autozero per scan add 1 channel measurement (around 2.5 s => 2.8 readings/s).
Activating Autozero at start should impact only the first scan... but here, it take 0,7 for the whole scan => 8.6 readings/s. That's near from the Fast mode spec : 8.8 readings/s.
My config is a PXI-8106 RT controler with a PXI-4351. I'm Using Labview 8.2.1 with corresponding RT module. And the driver for the 4351 is ni435x 2.5.2 / traditional DAQ 7.4.4
Regards,
Ludos

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NI PXI 4351 read temperature

Hi,
I'm trying to read temperature from TBX-68T connected to NI PXI-4351.
I see PXI-4351 in my hardware explorer, it show me right data in test panel.
But, I can't found any tools for reading temperature in LabView!
I installed drivers for NI PXI 4351
http://joule.ni.com/nidu/cds/view/p/id/285/lang/en
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I use LabView 10 and I have NI DAQ Traditional 7.4.4
so, I confused. How read temperature?

JaredRo wrote:
Hi kmcdevitt,
The SC Express product family was specifically designed to take advantage of the PXIe architecture and therefore the timing circuitry on the PXIe-4353 is not designed to be compatible with the PXI platform. There are no plans to design any of the SC Express products in the PXI form factor.
Jared,
Please explain what it is that makes the PXIe-4353 so special that there can not be a PXI-4353.
This 32-Channel, 24-Bit, Thermocouple Input Module does 90 S/s/ch sample rate in high-speed mode or 1 S/s/ch sample rate in high-resolution mode. Surely you are not claming the the PXI platform's architecture and timing circuitry can not hadle the troughput generated by the 32 channels of 24bit data at 90Hz.
Jared, it is not a pleasent fealing to be prommised that the new signal conditioning cards are going to be made for your soon to be purchased PXI-1045 chassises, and later find out from an Applications Engineer Jared that it has been in the plans to never make PXI versions of signal conditioning cards. How would you feel if you purchased about 30 PXI-1045 18 slot chassises with PXI Embedded RT controllers with the promiss that if you bought the controllers and chassises that NI would continue to develope new Signal Conditioning and Other PXI Cards for your chassises. Just buy them, and the new PXI cards will come. How would you feel when you were told to be patient and just wait till next years NI week. How patient would you be after the second year of being told to be patient until the next year's NI week? How patient would you be after the third year of being told to be patient until the next year's NI week? I have been recently asked to be patient again. NI Week 2012, there may be something. And now you tell me that there will never be anything.
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I have a PXI-8105 controller in a PXI-1045
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Well, I don't have ready access to a LV PC and for some very odd reason, my attempt to search for "error code" (and even just plain "error") on the ni website returned 0 hits?!? Strange...
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Hi,
My question is, why do you think Thermocouples are not transducers? In the application with NI 435x, thermocouples are considered transducers just like thermistors, etc.
1. You may want to take a look at examples here:
C:\VXIpnp\WinNT\NI435x\examples\CVI
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Claudia-
Thanks for the response.
Regarding the CJC- When I switch it on, the temperature readings I get are very random, roughly negative 1 degrees. (I am operating right now at room temperature, and will be using J-type TC's to measure ~43 degrees C). Also, when I use the built-in CJC, the aquisition rate seems to slow down considerably. When I use the "user specified" everything seems to be ok, including the aquisition rate.
I measured the resitance of the Thermistor on the TBX-68T and it was about 5000 Ohms, as expected.
Just to make sure: When using the TBX-68T, do I need to hard-wire a thermocouple to Channel 1/auto-zero and another to channel 0/CJC? Because I connected a TC to channel 0 right now, but I wasn't 100%
sure.
I've attached my main vi and two sub vi's that I am using for the voltage aquisition part of my project. (Note:the current measurements are just voltage measurements multiplied by the recipricol of the resistance it was measured across, ie. 10).
I would like to keep this file as is because it writes to a file exactly the way I want it to. I'd like to have the temperature aquisition with the 4351 in the same vi as the 6030E so that they both stop and start at the same time. I am just not sure how and where to log the temperature data since there will be fewer data points than the voltage data. Any suggestions? Should I write two separate files? can I somehow append them?
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Duplicate post

Cannot detect PXI 4351 channels

Hi there. I am new with labview and also the NI products. I just got myself a PXI 1042 controller with PXI 4351 card. I got to know that DAQmx can't be used to program the labview. I am using labview 8.2.
I can detect the card under DAQ traditional in MAX. How do I assign the channels in Labview 8.2? I can see the DAQ traditional in the Instrument I/O, but I dont know how to go about assigning the channels. I am only trained in DAQmx and I can't find any samples in the using traditional DAQ in 8.2.
Please help.

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Hey Grocket,
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PXI-4351 reading rate

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