USB-6501 static problems

[stilly32]

Thanks for the info - if you dig up any specs on the bad cable feel free to post it so others can avoid it. I know we've had some issues with poor quality cables in the past but this is the first I've heard of them linked to this error.

Thanks!

Andrew S

[peter_dtn]

found out that the 6501-OEM is sensitive for EFT (Fast Transients). If you generate fast transients in the neighbourhood of the 6501 PCB (10..20cm) the on-board microcontroller resets and the USB connection is lost. Maybe there are some high-impedance circuits on the board (reset-circuit) or open inputs. The board we have is one of the first series.

EFT is normally generated by relays switching loads..

Do more users see this behavior when the 6501 (OEM) is used near relays ?

regards from the Netherlands

Peter

[Axel Villamo]

I do have a problem with the ni-6501 units.

In my setup I log IOs and control a relay with a 6501 continually with a netbook. Nothing else is connected to the computer and a short quality USB cable is used. After a period (14 days last time) the 6501 breaks down. The green diod if of and I need to disconnect and reconnect the unit to get it working again.

The problem could come from:

1. Faulty USB driver or chipset.

2. The labview code.

3. Static electricity

4. Nearby relay that interfere.

This is a problem for me and as of now I do not know what causes the errors.

Input are appreciated.

[PK-EngineeringArts]

I frequently (daily) see the issue of resetting USB-6501.   I have seen static discharge cause the reset and have also noticed electrical noise can cause the reset (example when a vacuum pump was switched on).  We are using the OEM version.   We have several USB devices on our instrument system (cameras, motor controllers, etc)  and the USB-6501 is the only device experiencing problems.

[Matthew-B]

Hi PK-EngineeringArts,

The resetting USB-6501 OEM can be due to any number of reasons. To give us a better idea of where to look, what error are you seeing? Is it error -50405 or something else? In addition, what version of DAQmx are you using?

In the meantime, a few things that I thought of that you could try in order to reduce the frequency of the resetting would be to ensure the grounding of the board is correct, try a different USB cable, use a different hub, or try a different computer if possible.

If none of these help reduce the frequency of the resetting, I would recommend creating a new thread since the last post in this thread was over three years ago. Creating a new thread will also help get you some potential solutions faster. Thanks!

Regards,

[SnowMule]

Build some protection into the signal conditioning if possible, bypass caps help. 

On the USB side, Moxa makes a USB hub that can withstand pretty big ESD spikes, but it's fairly expensive.  Startech makes one with lower ratings and about a quarter of the cost.

Also make sure that under device manager, "Allow the computer to turn this device off to save power" is unchecked.