USB Storage

[russedwards]

Hi everyone

 

Is there a way to store data table information on to a USB pen drive?

 

My customer does not want to use the SD card - as they do not want their operators opening the PLC cabinet, and they have no way of using wireless transfer in their location.

 

I haven't been able to find anything suitable yet!

 

Thanks

Russ

[Michael_P]

Hi Russ, 

There is no method of performing this action to date. There is no USB connection on the PLC The USB to serial converter is used to communicate from the software to the PLC and only operates well as there is a driver contained within the software. Therefore if the same concept were applied to saving to a USB like it were an SD card, this cannot be performed as the PLC does not have the driver or the capability to support the USB to serial converter on its own, nor does the USB have the ability to host software. This is why any information exchange uses a PC or other process/software driven operation other than standard flash memory like an SD card. 

This can be performed on the UniStream controllers using the USB ports. 

Hope this helps to clairify

Mike

[Alexander]

If the operators have access to a PC they can use our SD card Suite that remotely connects to the PLC to view the contents of the SD card. This will allow an operator to view, download, and upload files that reside on the SD card of the controller. The information can be saved from the SD card and placed onto the USB drive, or saved from the USB drive and uploaded to the SD card.

 

This will require a serial or Ethernet connection from the PC to the PLC.

[MikahB]

Russ - I had a similar issue and solved it using a Micro-SD to SD-Card extension cable (this one, in fact: http://www.amazon.com/Manufacture-Sdhc-micro-Reader-Extension-Cable/dp/B0085GGO92/ref=sr_1_3?ie=UTF8&qid=1429124566&sr=8-3&keywords=sd+cable+extension).

 

I then mounted the plastic housing on the end o the cable to the outside of the enclosure and now you can get to the SD card without any trouble.

 

There is one catch (of course).  The PLC will not see the eject notification when you remove the SD card, so it goes along thinking (and indicating) there is an SD card present when there is not.  Only way to get it to reset is to restart the PLC.  For my application it's not a big deal - hopefully it's okay in yours also.

[russedwards]

Hi Mikah

Did you ever find a solution to this? I'm not sure I will be able to easily cycle the power to the plc after each data transfer.

[Flex727]

Is the reason you can't easily cycle the power because your application can't allow the PLC to be offline for 5-10 sec, or because you can't easily access a power switch? If the latter, you can use SB 300 to re-boot the PLC without having to access power.

[MikahB]

Hi Mikah

Did you ever find a solution to this? I'm not sure I will be able to easily cycle the power to the plc after each data transfer.

 

Hi Russ.  Unfortunately, I do not believe there is a solution besides resetting the power, the mechanical eject requirement is part of the SD slot spec.  If Unitronics could magically add a "Reset SD Status" bit, that would do it, but short of that I have no other solution.