topic Re: Simple Dual Redundancy in Components

Simple Dual Redundancy

ninjaphil — Tue, 04 Aug 2009 22:40:49 GMT

Please provide feedback, comments, and questions on the

Reference Design for Simple Dual Redundancy

in this thread.

Re: Simple Dual Redundancy

toddho — Tue, 23 Mar 2010 14:52:09 GMT

Can not get it to install in 8.6.1. After the instillation screen asks where you want to install the files up pops another screen that says no software will be installed and the next button is grayed out.?

Todd

Re: Simple Dual Redundancy

Doug_S — Tue, 23 Mar 2010 15:52:08 GMT

If you previously installed it for another LV version, I believe that you must uninstall it before reinstalling it.

Re: Simple Dual Redundancy

toddho — Tue, 23 Mar 2010 16:22:12 GMT

Yes, you are completely right. I now have it working. Thank you!

Does anyone know if there is something like this already written for TCP/IP? I will be trying to use this not for compact RIO but on servers. I am afraid that using serial ports may be hard to do... Hardware wise.

Thanks

Todd

Re: Simple Dual Redundancy

LaRisa_M — Wed, 02 Jun 2010 22:38:11 GMT

How do you specify which controller will be the Primary and which will be the Secondary?

Re: Simple Dual Redundancy

toddho — Thu, 03 Jun 2010 13:42:26 GMT

I think a start up configuration file assiging a functional global variable is probably the more eligant way but I just have two identical versions but with a "Primary" boolean control setting the functional global that I change on the primary and the non-primary. Then in my decision making it checks to see if it is the primary and takes or gives control accordingly.

Hope this helps

Todd

Re: Simple Dual Redundancy

irfan789 — Thu, 06 Feb 2014 06:32:26 GMT

how to communicate the two sb rio Boards for redundancy i mean which kind of protocol could be better out of ethernet and rs 232 ?

Re: Simple Dual Redundancy

Mashfique — Wed, 19 Feb 2014 04:32:18 GMT

hello everybody

is there a way to make a redundant system of two sbRIO boards ?

Re: Simple Dual Redundancy

lharding — Mon, 24 Mar 2014 17:48:27 GMT

Ethernet protocols such as TCP will provide much higher data transfer rates than RS-232. Some Single-Board RIO (sbRIO) boards do offer RS-232 connectivity, but this is generally to support devices or instruments which require it.

Communication of data between multiple sbRIOs for the purposes of redundancy would be most easily handled using a standard ethernet communication protocol, such as TCP or UDP. Your selection of protocol would depend on the requirements of your application.

Re: Simple Dual Redundancy

lharding — Mon, 24 Mar 2014 18:43:03 GMT

I should add that the Simple Dual Redundancy (SDR) is designed for slow-speed systems (<1Hz) and is set up for serial ports. Using the SDR with RS-232 serial is a good option for systems like this.

Re: Simple Dual Redundancy

lharding — Wed, 02 Apr 2014 18:00:34 GMT

I put together a quick example of using the SDR with two NI sbRIO-9612 boards (LV2013). It uses network shared variables, so I would recommend using a different mechanism for RT Target to Host communications (such as Network Streams) for any serious applications. To run the example, you will need:

null modem cable
NI CompactRIO Software, plus the following Add-ons:

NI-Serial RT
Network Variable Engine

The example is run be toggling the "Health" values for each board, causing the board with a higher numeric value to assume the role of "Active" unit and relegating the other to "Slave." Here are a couple of screenshots of the example project:

Re: Simple Dual Redundancy

Marco.Kwok — Fri, 11 Apr 2014 10:16:14 GMT

hello all,

Thank you for making a wonderful reference for SDR.

I want to share with you about my experience when creating rtexe for my real-time target.

When you test the VI in LabVIEW, it works as expected.

However, after you build the exe and deploy it on your cRIO/cFP, it does not work,

You will see an error coming out with code 1026, saying VI reference is invalid.

My work around is to open the SDR Start.vi. Replace the open reference function with Static reference, as shown below:

Now all will work just fine.

If Anybody know the method to use dynamic reference on RT target, please post here too. I believe many of us will appreciate it.

Attached my set of modified SDR reference used under LabVIEW 2012

Cheers,

Marco Kwok