20ma current output not achieved for NI 9265 when external supply is 24 volts

[bobcat7]

With an external supply of 12 volts (and 1k load) the NI 9265 channel was able to swing from 4ma to 20ma without a problem. With an external supply of 24 volts, however, the maximum current it produced was approximately 12.67ma (12.67 volts across 1k). Why would this be, as the external power supply range is 9-36 volts?

[rpursley8]

How did you get 20 mA driving 12 Volts into a 1k load?

That aside.  It looks like 12 Volts might be the maximum that is output from this module.  The power supply runs through an internal DC/DC coverter which probably is regulated to 12 Volts.

Hopefully an NI guy will respond to confirm or deny.




Message Edited by rpursley8 on 03-06-2008 03:49 PM

[bobcat7]

Indeed, what I wrote originally cannot possibly be correct. In my prior test with a 12 volt supply and 1K load, the max current would have been 12ma. A re-read of the output specs indicate a max compliance voltage of 12v (20ma through a max load of 600 ohms). Thanks for the reply.