Circumvent 9233 IEPE

[A.S.]

Hi,

Please refer to the following KnowledgeBase:

http://digital.ni.com/public.nsf/websearch/F09B866779C7C1E786256E38005AAD62?OpenDocument

and the following Developer Zone

http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=D34242F36D5E0A59E034080020E74861&p_...

on creating and writing TEDS data.

Hope this is what you were looking for. Please let us know if otherwise.

Have a great day!

A Saha

Applications Engineer

National Instruments

[geneM]

I'm in a similar situation.  The pre-sales information I got indicated that the current source on the 9233 could be turned off.  Now that I've got one, I find it can't.  I'm trying to figure out what devices will be able to drive their signal into a load with a current source and have the following questions I'm hoping you can help with

1) Should I be able to hook a standard bench top function generator into the 9233 for simple VI testing?

2) Should a low level (< 1 Volt) device with moderately low output impedance work with the 9233?

3) Is it possible to disable the current source by cutting an IC lead or circuit board trace?

4) Is NI planning a product similar to the 9233 without the current source?  One of the PXI bus DSA boards would be ideal for users looking for a high speed, high accuracy digitizer with on board anti-aliasing filters and PGAs.

Thanks for the help - Gene Massion

[.avi file]

Greetings:

  Listed below are some useful links about programming virtual teds in LabVIEW.  Could you please let us know if you are looking for something very specific.

http://zone.ni.com/devzone/conceptd.nsf/webmain/2B71D966B0E41FB586256D9B0068BCBC?opendocument

http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=D34242F36D5E0A59E034080020E74861&p_node=DZ52516&p_source=External

http://digital.ni.com/public.nsf/websearch/F09B866779C7C1E786256E38005AAD62?OpenDocument

Thanks much
Avi

[geneM]

Avi

Thanks for the TEDS information.   I am looking for something very specific.  I want to be able to turn of the current source in a cRI-9233.   I'm a little unclear how to use the TEDS information.  Can I turn off the 9233 current source by programming a virtual TEDS in Labview?

Thanks - Gene

[Jack_A.]

Gene -

No, you are not able to disable the IEPE current source for the 9233 by using a TEDS sensor or a virtual TEDS file.  The design of the hardware on the 9233 is so that the IEPE current source is always present.

Jack

[mdillon@home]

Gene Massion posted the following questions, Below are some answers.

1) Should I be able to hook a standard bench top function generator into the 9233 for simple VI testing?

YES - Any number of co-op students have done this accidentally by leaving the ICP power turned on.

2) Should a low level (< 1 Volt) device with moderately low output impedance work with the 9233?

Likely So. - The real question is whether the device can sink the 2mA current @ 24 VDC coming from the 9233.  If it doesn't fry the device, the only measureable effect of the IEPE power is at 0 Hz, which gets filtered by the 9233 coupling circuit anyway.

3) Is it possible to disable the current source by cutting an IC lead or circuit board trace?

I wouldn't reccomend this.

4) Is NI planning a product similar to the 9233 without the current source?  One of the PXI bus DSA boards would be ideal for users looking for a high speed, high accuracy digitizer with on board anti-aliasing filters and PGAs.

No comment.

[mdillon@home]

Regarding Jack A.'s reference to the PCB 401A04, one should keep in mind that this device is easily damaged with input levels above +/-500mVpk or so.  Don't quote me on the actual threshold, but I have specific experience with these devices and their intolerance to high input levels. 

[.avi file]

Greetings!

   An answer to the question on a product similar to 9233 without a current source, this is something we at NI are looking in to. I would recommend filing a product suggestion at the following link also.

 http://digital.ni.com/applications/psc.nsf/default?openform

Thanks and hope this helps
Avi Harjani

[Vahan]

Regarding mdillon's post.

I have tested the PCB 401A04 with cRIO-9233 at input voltages up to 5V pk for several hours, but  no damage was observed.

[duncan carter]

I have also used the PCB 401A04 with a USB-9233 combination and experienced failure of the PCB 401A04 for no apparent reason except for possible transient overvoltage while connecting the device to a signal generator with output level set within the normal range of of the 9233 and after about four months of use.