9264 offset

[Řeřicha]

Hi everyone,

i have two cRIO analog output modules 9264 (Uout<+10V;-10V> and 4mA per channel).I need output range <0V;18V> for all channels, but I would like control output range. I think i could use cRIO analog output module 9269 or DC supply source, but i am not sure. I would hate to see my cRIO modul in fire

My solution: 

 

What do you think about it? Could you suggest better solution (price/(safety,serviceability...))?

[Stefo]

Hi Rericha,

now i have to be careful what i say 🙂 in fact I believe it could be possible to use external power supply with 9264 nodule, because it has isolated outputs. However, keep in mind that this module doesn't have Chanel to Chanel isolation.

NI 9264 with DSUB Isolation

VoltagesChannel-to-channel...........................None

Channel-to-earth groundContinuous .................................60 VDC

In fact it is what you attached, just I included internal circuity as explanation why i believe it should be possible.

regards,

Martin Stefik

[JamesBeams]

I can confirm this is possible, but you must be careful what the source of your DC offset is and what it also references.  If you connect your with the external voltage to the AO output of the 9264, then that supply will have to not be ground-referenced otherwise it won't be able to float above ground and you won't get what's expected.

If instead you connect the output of your DC voltage source to COM then the entire bank of 9264 outputs will be referenced to that DC source voltage, and the isolation will definitely allow a higher voltage output (I've done this to create 12-16V before with a benchtop DC source).  As Stefo mentioned, be sure the DC offset doesn't exceed 60VDC though.

-James