Chris Elston

Posting via a member of forum. I merely pass on, I am not the employer Associate Control Systems Engineer for details see www.centralsan.org

Great! You can even do that on a real computer too. I haven't had time to make the mobile skin the same colors as the main website. I come from the school, functionally before form...

When you are on your phone. Do you see the SKIN option at the very bottom? If you select MrPLC, then GO, does that switch it for you?

Daryl, I wrote an article about BIT SHIFT LEFT. http://www.mrplc.com/kb/index.php?article=71 Most of the time engineers will use this to track a process. The article describes how to apply it.

done...

Here is an article I wrote for the same reasons. http://www.mrplc.com/kb/index.php?article=13 but most have already posted examples that should work as well.

No counter balance is tough, and we don't have the weight. We have to weigh in at 120 lbs. And the robot is 115 lbs now. There is no ramp function from set -point to set - point...that's a good thought..... The update rate is 100 HZ for the loop. We got this to work by having the same PID tune, but different motor limits. So the output limit on the up direction is +1 on the speed controller and -0.3 on the speed controller going down. This ended up working really well. We are quite pleased with the results. Thanks for all your suggestions. I'll post a video of the robot when we release it to the public very soon.

Hugh Jack has allowed his PLC Programming books for download on MrPLC. Have to seen these? http://forums.mrplc.com/index.php?autocom=downloads&showfile=156

For small machine I/O I am a BIG FAN for Compact Logix L35E. You get an ethernet port "ethernet I/P", expandable rack. If you don't need motion the L35E is a sweet deal. I agree that Control Logix can be over kill for smaller machines. Or if you don't have motion, or the need for multi layers of communications. You can do motion with an L43 Compact Logix, but for straight up digital I/O, you don't need it. I would recommend the L35E Compact Logix. My favorite still today cost to performance wise, and I get to use RS logix 5000 software, which is killer compared to Rs Logix 500 software. User Define Tags in RS Logix 5000 saves me soooo much time, it's not even funny.

At one point, I wrote a whitepaper on this. Some say, I didn't do a good job on explaining it in my whitepaper, so sorry if it is hard to understand. http://www.mrplc.com/kb/index.php?article=85 At the bottom of the article, I posted my sample code if you want to open it up and take a look.

You can use a bit shift to track the position. I wrote a white paper on how to use two bit shifts in a process with reject in the end. http://www.mrplc.com/kb/index.php?article=71

Is this what you want? http://forums.mrplc.com/index.php?app=downloads&showfile=595

Now that I have this problem fixed: http://forums.mrplc.com/index.php?showtopic=20796 I am able to configure my DeviceNET Master card no problems using the Ethernet IP driver / RS Linx Classic 2.55, a crossover cable and RS Networks. Works great.

I think I already know the answer to this...but hey, maybe I'll learn something new. Is there any other ways to configure a 1756-DNB/B module without a DeviceNET converter box? I don't have mine anymore. I had a 1770-KFD module but not any more. It's a series B so I don't have the USB port on this one. I might have to borrow either a 1770-KFD / 1784-PCD or buy another one. Just checking...

This is one of those days where I think I need "two heads are better than one" deals. I've got an 1756-ENBT/A module that has firmware 4, installed I am running version 17.01 RS5000. I can't seem to get a connection through it to PLC program. I have the firmware 4 EDS file installed in RS Lite. I also can ping the module just fine on it's IP address. What did I miss? I would like to PLC program through the 1756-ENBT/A by setting up either an Ethernet driver or Ethernet I/P driver in RS LINX. Linx sees it ok, but it won't drill down into the rack and expose the CPU to go ONLINE. I am only seeing the module at the top level...and I have a head ache today..

Figure this out on Friday. So I thought I would post the solution. Basically, I ended up going to my local AB distributor to figure this out and get to the bottom of this. Kudos to Bob Winters at Kendal Electric for helping me out and having some hardware on hand just in case it was the chassis. However the problem was not hardware. I had version 2.54 RS Linx Classic installed on my laptop. When I arrived, Bob tried his laptop, which has 2.55 RS Linx and it connected no problems and drilled into the rack just fine. At this point I assumed all the hardware was ok and it was a software or PC problem. So naturally, I uninstalled 2.54 RS Linx and installed 2.55 version. It worked like a champ. Now according to the Firmware Matrix on AB’s website, for version 17.0, you need a minimum of RS Linx 2.54. I'd say you better bump up to the highest version possible. I did have TWO COMPUTERS if you remember; I had a laptop and a desktop I was trying to connect with. Both had version 2.54 RS Linx. After uninstalling and reinstalling 2.55 on both laptop and desktop I was able to browse the rack. I also was using a crossover cable to eliminate and switch/hub problems. So the lesson learned here is make sure you have the latest version of RS Linx Classic installed on your machine. Why this happened, I dunno. Maybe someone can explain it. Bob thought 2.54 might have been a corrupt install. I would agree with that except, it happened on two machines. I also tried 2.54 on a version 17.0 CPU / 4.008 ENBT. I also downgraded to version 15.0 CPU / 3.9 ENBT neither firmware versions seemed to affect it, until I upgraded to 2.55 RS Linx. I was able to browse the rack with version 2.55 after upgrading back to 17 and 4.008 ENBT as well, so not problems after that. I did also have the latest EDS files installed with RS Linx 2.54 for both CPU and ENBT card. I used the EDS hardware install wizard. I also did try and blow away my harmony as well. None of these suggestions worked until I upgraded to 2.55 RS Linx Classic. Both DF1 driver and Ethernet driver configured in RS Linx Classic was able to drill into the rack after the 2.55 upgrade. So not only did the ENBT not work with 2.54, the DF1 driver would not either. That might be clues to if you experience something similar. Good news is, I am up and working now!

Tried flashing down to version 15.0 on the L61 and 3.0 on the ENBT module like Ken Roach, but same results. I didn't flash down the DeviceNET card even though the firmware matrix calls for 6.002 for the DNB card. It doesn't matter anyway. Neither DF1 or ENBT will drill into the chassis. I am confirming that I am using RS Linx Classic 2.54 and RS Logix 17.0 as well. Tried moving the CPU around too, as you can see in this latest setup here.

I dunno. I may have a Chassis Problem because I believe, I should also be able to drill into the rack through DF1 driver, and I get the same. I can see the Processor, but nothing in the rack.

Here is my Wireshark capture. Not sure what I am looking at but it doesn't look the same as yours after the initial first level. ENBT_dump.zip

I tried to clamp down on my mask. That didn't seem to help. Also I tried with two PC's one desktop and one laptop and they both do the same. I'll try the slot swap in a second.

I did an RS Who, then right clicked on the ENBT. All I got was an Upload EDS option, so I did that just to check what the EDS was. It was in fact version 4.0. That was a good sign. I tried blowing away harmony, but still no browse. It acts like it's "trying". I get the "+" then alittle wait, then a "-" with no drill down into the back plane. Any other bags of tricks? Maybe I'll try another firmware version just for kicks and giggles.

Catch 22 then. Once I figure out why I can't get online through the ENBT, I'll be able to get online with the DNB. Great. LOL....

Here is an RS Linx Screen Shot too. No drill down to CPU and back plane.

I can also browse the ENBT through HTTP.

Here is a screen shot. Yup IP looks good. I can ping the card ok.