Default Settings for Digital Lines? USB-6009

[diarmaede]

Hi All,

I am using the digital lines on my USB-6009 to control normally-opened SSRs.  When I turn the system on, I'd like to have the digital lines on the USB-6009 automatically configure themselves to be digital output lines set in the "Low" position, so I don't switch on my SSRs until I give the command.  Is there a way to do this?

Thanks.

[SnowMule · Accepted solution]

Can't set default states on 600x DAQs, unfortunately.

Have to do some engineering on the hardware side knowing the lines are pulled high when the DAQ is initialized; and if some combination of outputs produces a hazardous situation, you'll need to stop that from happening in hardware.  Good practice to do anyways.

Other option is to use an analog output, those can pump a little more current than the DO's and default at 1V which usually isn't enough to toggle SSRs.

[diarmaede]

Thanks.  That makes sense.  I've used the analog channels in the past, but I wanted to "do it right" this time.  Maybe doing it right is the wrong way to do it in this case.

I'm going to transfer the whole setup to a CompactDAQ chassis as soon as my new NI toys come in.  I'll be using a 9401 DIO module for the digital lines.  Can I set that unit up to default to the conditions I require?  But, yes, I will make sure that the lines are automatically switched to the low position if when the system is set up.