scc 2345 and lp04

[E@bio]

I have connected the signal from and accelerometer amplifier to an SCC-LP04 filter module.  The module is located in slot J1 of an SCC-2345 enclosure with the external power supply and DAQ cable connections on the rear of the enclosure.  The DAQ card being used is a PCI 6221.

 

I am getting a flat line response sitting at 10.5 volts when I look at the signal in MAX.   If I unplug the signal from the accelerometer the output seen in MAX remains at 10.5 volts.

 

In the current setup all the components are brand new.  I have used similar combination of hardware in the past with out any problems.  I am at a loss as to what is wrong. 

[BrowningG]

Hello E,

Thanks for contacting National Instruments. 

It is normal for an open connection being measured by a DAQ card to return a railed voltage value.  This is due to the fact that the inputs at this point are floating.  Most likely there is an issue with the hardware setup. 

Try running the <a href="http://digital.ni.com/softlib.nsf/websearch/C8D5A739965EF222862571D900780D3C" target="_blank">DAQ Diagnostic Utility</a> for your DAQ card; this will attempt to locate any errors in the DAQ device. &nbsp; Also try connecting a known voltage source directly to the DAQ card and to the LP04.&nbsp; If the voltage rails when using the LP04, but not the DAQ card, it is most likely an issue related to the LP04.&nbsp;

We have seen case where the LP04 when used in a SC-2345 with a PWR02 connector has caused a malfunction.&nbsp; To attempt to get around this, try connecting the PWR02 module to the SCC-2345 before you plug it into the wall.&nbsp; This will allow for the +/- 15 Volt power supply rails to come on at the same time.&nbsp;

Please post back if you have any questions.&nbsp; If this troubleshooting does not work for you, contact our <a href="http://www.ni.com/ask" target="_blank">technical support</a> to speak to an Applications Engineer who can determine if the device needs to be returned for repair. &nbsp;