How to control an NI 6343 on shutdown

[LabviewRat]

I am using the NI USB-6343 and my digital outputs (P0.1-0.8) are firing during computer shut off. The digital outputs are wired through some gate drivers for isolation purposes which in turn trip some relays to control higher voltage lines. The Digital outputs do not fire when the program is closed and work as intended during operation. The only condition in questions is when there is a power surge or the computer is completely shut down. I am using the executable on a PC with NI run time. My labview version is 2017. I have a hardware solution in mind but was wondering if there was any software solution that would resolve this problem. Any help would be greatly appreciated.

[GerdW]

Hi Rat,

The only condition in questions is when there is a power surge or the computer is completely shut down. … but was wondering if there was any software solution that would resolve this problem.

Ok, you want a software solution for the case of power surges or computer shutdown.

Really? Software in case the computer is shut off???

I have a hardware solution in mind

Go this way.

As should be done anyway for "higher voltage lines"!

[LabviewRat]

Thanks for the quick reply. I will resort to a hardware solution for this then. I understand power surge can throw a wrench in the works but was under the impression that a digital out shouldn't run high on shutdown. If this is a naive assumption let me know as I don't have a ton of experience with the DAQ's startup or shutdown protocol. Thanks!

[RavensFan]

I don't know whether something would or should run high or low on a computer shutdown.

But what I do know is that if a PC loses power, devices connected to it via a USB aren't going to be in any known state, thus how can you rely on a digital output to remain high or low when device is no longer powered in a way to cause it to remain high or low.

[Ben]

Safety Modules are now available.

Ben