Extending a DAQ USB cable 100ft

[Mark Balla]

I'm working in a food plant and we are required locate the PC 100ft from the USB Daq device during testing (Stay out of production's way).

The client bought a USB to Ethernet converter box to do this. It was tested with the system and it seemed to work.

Today it is not working. We can find the Daq device in Max no problem but as soon as we start acquiring data The device gets lost and Max no longer sees the device.

We took the computer and pluged it into the daq device bypassing the USB extender and sure enough it worked with no problems.

The USB to Ethernet convert specs say it can transmit up to 1.5MB/s. I am only sampling at 100 Samples /sec which is nowhere near that rate.

Has anyone else experienced a problem with USB extenders? If so how did you fix the problem? or

Does anyone know of a proven USB - Ethernet - USB extender that will work with USB 2.0?

Thanks

Mark

[David Novak]

Check out the guide I put together: TIED IN KNOTS – A Must-Have Guide to Untangling USB Extension Options for PC Based Automation. It describes several methods for extending the USB.

Best Regards,

David

[dblk22vball]

No that it will be much help directly, but here is a post from the other forum.

From NI poster:

We've continued testing on hubs and extenders, but have yet to find any that work to our satisfaction (%100 of the time for every chipset). We have found that name brand powered USB hubs usually work and that active extension cables usually work. We've also found that most USB to ethernet and "wireless" USB extenders either don't work at all with our products, or have unacceptable throughput and reliability issues.

[ShaunR]

I'm working in a food plant and we are required locate the PC 100ft from the USB Daq device during testing (Stay out of production's way).

The client bought a USB to Ethernet converter box to do this. It was tested with the system and it seemed to work.

Today it is not working. We can find the Daq device in Max no problem but as soon as we start acquiring data The device gets lost and Max no longer sees the device.

We took the computer and pluged it into the daq device bypassing the USB extender and sure enough it worked with no problems.

The USB to Ethernet convert specs say it can transmit up to 1.5MB/s. I am only sampling at 100 Samples /sec which is nowhere near that rate.

Has anyone else experienced a problem with USB extenders? If so how did you fix the problem? or

Does anyone know of a proven USB - Ethernet - USB extender that will work with USB 2.0?

Thanks

Mark

1.5 MB/s is a bit of an odd number. 10BaseT is 1.25 MB/s and 100 BaseT is 12.5.

If you have been using it for a while and its stopped working. then it probably has developed a fault and just needs replacing. (Just though I'd clarify that since it was not clear).

If you quickly tested but found it unreliable over a period. Then there are a couple of things you can try (I presume you've eliminated the usual stuff like dodgy wires and poor connections).

Some devices only support half duplex and can get confused by the probing if set in auto, or can succeed in full auto due to response times but fall over when the inevitable contention occurs. You can try explicitly setting the PCs network to "Half Duplex" and see if that helps.

If your device supports wake up on lan. It could be going to sleep. To wake it up, you have to send a "magic packet" your documentation may tell you more.

What is the model/manufacturer of the device?

[Mark Balla]

Check out the guide I put together:

David I'm flattered that you joined LAVA for the sole purpose of answering my question.

Have you tested any of these with an NI DAQ USB device? (Please, no more links just reply to this thread)

No that it will be much help directly,

Thanks dblk22vball it did help. Now I see that this may be a more difficult problem than I had thought.

If you have been using it for a while and its stopped working. then it probably has developed a fault and just needs replacing. (Just though I'd clarify that since it was not clear).

If you quickly tested but found it unreliable over a period. Then there are a couple of things you can try (I presume you've eliminated the usual stuff like dodgy wires and poor connections).

What is the model/manufacturer of the device?

The device is made by "Black Box"

Single USB to CAT5 Extender, 50 m

IC244A-R2

http://www.blackbox.com/Store/Detail.aspx/Single-USB-to-CAT5-Extender-50-m/IC244A-R2

We tested it breifly 3 weeks ago but were distracted by other issues at the time to fully test the reliabiltiy of the connection.

Update:

After talking to NI support we covinced our selves that it must be a USB power dropout issue.

By the end of the day we had powered hubs on both ends of the extention and we would still lose connection.

Tomorrow we will try one that is rated for USB 2.0 speed and is externally powered.

Icron USB Ranger 2101

http://www.icron.com/products/usb_new/usb20_ranger_2101_2104.php

I will let your know how it worksout

[ned]

I'm working in a food plant and we are required locate the PC 100ft from the USB Daq device during testing (Stay out of production's way).

The client bought a USB to Ethernet converter box to do this. It was tested with the system and it seemed to work.

The device is made by "Black Box"

Single USB to CAT5 Extender, 50 m

IC244A-R2

http://www.blackbox....-50-m/IC244A-R2

Sorry for stating the obvious here, but your client is aware that USB to Ethernet is not the same as USB to Cat5? If they're trying to use an existing ethernet network it's not going to work - they need a dedicated Cat5 cable just for this device.

[Chris Davis]

Tomorrow we will try one that is rated for USB 2.0 speed and is externally powered.

Icron USB Ranger 2101

http://www.icron.com...r_2101_2104.php

I think you will have better luck with the Icron extenders, they are designed for USB2. I'm still not sure they will work, but they have a better chance than the blackbox USB1 extenders.

If your client is up for another purchase, you might want to checkout NI's Ethernet DAQ devices. If they meet your needs, and don't break the bank, they are much more reliable over long distances. They can also be clocked together so that you can get more channels of input. I have used three NI-ENET 9215's in such a way and have been very impressed with thier abilities. It looks like the 9205 has 32 channels, and a very small package, but you didn't mention your rate/channel or channel count needs, so I don't know if it will do what you want.

You might also consider bringing the computer closer to the USB device, via a "weather proof" box and the appropriate connectors. You could then use VNC, or a KVM extender from blackbox to extend the monitor, keyboard, and mouse.

[David Novak]

Have you tested any of these with an NI DAQ USB device?

Your sample rate rate and the USB extender data rates are two different things. The 1.5MB/s means that the converter does not support USB 2.0's high speed mode. If you're DAQ device operates using the USB 2.0 high speed mode, then the converter won't work.

I've not had the opportunity to test extender devices with NI DAQ USB devices, but I see no reason it can't be made to work. The USB to CAT5 extenders are maybe the worst choice for extending USB. Theoretically, they should work fine (USB 1.1 only), but all they are doing is transmitting the USB signals over CAT5 cable. It never enters the ethernet domain. If you pick up any noise, these extenders are likely to cause problems. Try keeping the bulk of the cable in the most electrically noise-free area of the installation.

Using USB hubs with 50m USB to CAT5 extenders is not allowed. The delays they add cause the communications path to exceed the USB's maximum allowed transmission delay.

Icron's Extreme USB devices impress me the most. They don't require additional software drivers and they fully meet the USB 2.0 specification. However, beware that they will add delay to the communications. I expect you will see that it takes twice as long to complete a USB transaction. If this is a problem, try an active cable which includes signal conditioning.

I hope this helps.

[Mark Balla]

The Icrons came in and they worked great.

They come with their own 5VDC 1.5 A supply and it must plug into the DAQ end of the cable not the PC end.

This caused another issue since the DAQ device is inside an electrical box stuffed full of other electrical equipment.

I have lots of room on the PC end of the cable and it would be nice if you could connect the power supply to either end.

But after cramming 2 more wall warts into the electrical box we fired it up and everything work.

We are running tests overnight to make sure it will be reliable over the long term.

I think for the final implementation where the cable needs to be 300ft form the DAQ device we will move to a ENET carrier.

Thanks everyone for your input.

Mark