12-02-2015 09:19 AM
Hello All,
I am using NI 9174 chassis and NI PS15 power supply which provide 24Vdc. connection are pin V wired to +24Vdc, pin C wired to -24Vdc.
But Seems like this connects pin C to ground too. Is there internal connection in the chassis that makes pin C connects to ground (enclosure)?
Now I have all my COM are connect to Gound which I don't have in my drawing.
Can any one explain this?
Thank you very much
12-03-2015 03:43 PM
Ya-hoo,
Have you checked the output of the power supply with a DMM? It might be worth making sure the voltage is what you think it is. I would also recommend looking through the manual for the NI 9174.
-aprillest
12-03-2015 03:48 PM
Yes, output of the power supply is 24Vdc.
12-03-2015 06:49 PM
12-04-2015 08:18 AM
I mean negative of 24Vdc power supply.
12-07-2015 08:25 AM
According to the user manual for the NI cDAQ-9174, (link) it appears that the safe voltage input range is 9-30V. A range of -24V to 24V would be a 48V range, which is outside the limits for this device. Can you use a lower power range (i.e. -15V to 15V) for your application?
12-07-2015 08:54 AM
Hi All,
I am sorry for the confusion. Here is the clarification of my wiring.
I am using NI PS15 as power supply and connection is as in the picture.
Thanks,
12-07-2015 10:07 AM
12-07-2015 10:12 AM
9174 is powered up and system seems working fine.
One thing I'd like to know is why the COM is connected to system GROUND once V and C of 9174 are connected.
Thanks,
12-07-2015 11:12 AM