03-28-2012 12:27 PM
I have a c9188 system with four thermocouple (9214) modules, two voltage (9205) modules, and one current (9203) module. The system was working fine and running with my vi's. When I attempted to run the program on Monday, I am able to read the thermocouple and current measurements, but the voltage measurements have completely stopped reading. I tried switching out the voltage cards without success. They do not read in the .vi or in MAX, and I have checked all of the physical connections. Any ideas why my voltage cards (both) would stop working overnight would be appreciated.
03-28-2012 05:16 PM
Sorry you are having difficulty...I have some questions to get started...
Are you getting an error or warning? In other words, what do you mean they have "stopped reading"? What if you attempt to read values out of the DAQmx read instead of graphing. Do you see any values at all? Are you running tasks on the other boards in the 9188 system? If so, what happens if you stop reading from those modules?
03-29-2012 03:21 PM
I am not getting any errors or warnings. By "stopped reading" I only mean that when I apply voltage signals to the terminals no response is observed either in .vi files or when observing single channels in MAX.
I am not running any other tasks on other chassis. The channels reading from the TC and current cards read values, but the voltages report values of zero, even when I apply reference voltages.
03-29-2012 04:18 PM
If you could test the input voltage, that will let us know whether the issue is with the modules or the connections. Use an external meter to read the voltage across the screws that coordinate with the pins you are using (channel and COM or channel to channel depending on your setup). It could be the wires have gotten loose or there is an issue with the source
Also, have you tried shutting down the entire system (chassis and computer included) and restarted? You could also try to reseat the devices. Lastly, try placing the modules in a different slot. Any luck?
Let me know how things go!