Micrologix/SLC crashing while online

[curlyandshemp]

I have ecperienced the online editing fault with SLC 5/04s in the past too. At one site I can make it happen everytime an edit is performed over DH+. The strange thing is that the CPU faults and it looks like it is wiped clean from the DH+ port, but connecting to the serial port the ladder is fine but the DH+ port is locked up. The only way to get past this condition is to download a fresh program. Tech Support was no help, they blamed the DH+ wiring (which works fine for about a dozen other PLC5s and SLCs). I eventually added a NET ENI and do the online edits over Ethernet with no problems.

That's what we have SLC 5/04 connecting via PCMCIA DH+ card.
As soon as another laptop uses the same file, BOOM crash on first online edit. Then its fine after that until the file is used on another laptop.

There are two of us here in this plant commissioning 8 machines, so who is ever available goes to the machine with the most up to date backup.

 

[dmroeder]

I have ecperienced the online editing fault with SLC 5/04s in the past too. At one site I can make it happen everytime an edit is performed over DH+. The strange thing is that the CPU faults and it looks like it is wiped clean from the DH+ port, but connecting to the serial port the ladder is fine but the DH+ port is locked up. The only way to get past this condition is to download a fresh program. Tech Support was no help, they blamed the DH+ wiring (which works fine for about a dozen other PLC5s and SLCs). I eventually added a NET ENI and do the online edits over Ethernet with no problems.

What version of RSLogix 500 were you using?

 

[Derek McFarland]

What version of RSLogix 500 were you using?

This was an ongoing problem that started when the system was installed with v6.20 (I think, ) and continues to this day with version 7.20 (I think, I am not at the site).

The problem occurred from more than one workstation that were connected to DH+ via KTXs. After migrating the workstations to Ethernet and joining them to the DH+ via a CLX Gateway, the problem continued. Adding the NET ENI has allowed us to aviod the problem, but it was never determined why it was happening or what to do to correct it. At the time, I dug out some old Rockwell technotes that showed how to troubleshoot DH+ with a scope and the traces didn't look much different than the ones in the technote.

Apparently this is not uncommon.

http://www.plctalk.net/qanda/showthread.php?t=10666

 

[Bob A.]

One thing that comes to my mind, is that AB provided a serial cable that would connect directly to a ML 1000 but they did not recommend connecting directly to the ML1000 from a PC. I eventually got the AIC+ for an interface to the DH485 port. When serial ports got scarce and I got tired of fighting the PIC driver, they told me to check out the UIC instead of the AIC+. It is USB to either DH485 or RS232 serial and it works great. The reason that they gave me was related to blowing up the port electronics due to different power systems, etc. That might be affecting you during your transfers on the ML1200 as well.

In regard to crashed CPUs, make sure that you don't have any division problems where you can divide by zero. That is the most common way that I ever found to fault a CPU.

Best Regards,

Bob A.

 

[OkiePC]

What is the watchdog timer set on? Assembilng edits can spike hte scan time, but should not wipe memory unless there is a firmware issue.



Serial port electrical incompatibility is a real issue, but I have never seen that with DH+. I have locked up the serial ports a number of times with similar symptoms...only a power cycle would get it freed up, and once toasted the serial port on a PC, before finally using isolated ground, and then later bought a little UPS for the roll around desktop we used.

If it were divide by zero, it could fault the controller, (which has not ever kicked me offline...maybe it could though...), but that should set fault bits and in a SLC will fault the processor unless you're programmatically clearing it.

If your program unlatches fault bits, add logic to make a copy of those bits first, and then when you get back on line, you'll have more evidence to work from.

To me though, this sounds like a firmware incompatibility issue.

 

[Picklemon]

I have had the same issue this week with a SLC5/05 (1747-L553C FRN 10) making an online edit over Ethernet.

The first time was when someone else was covering for me and needed to make an online edit. The second time was when I came back and tried to make an online edit.

I am using RSLogix 500 7.30 and RSLinx 2.52.00.17.

I am currently working with my Rockwell vendor to figure out the issue. I'll post back when we have an answer.

 

[Picklemon]

And I am using a Dell Inspiron 6000 with WinXP SP2

 

[Picklemon]

Here's what my vendor replied with:

There was a PSA (Product Service Advisory) that just went out last week for 7.30 of RsLogix 500.... and guess what? The symptoms are exactly as you describe. Please download 7.30.10 from the www.ab.com and this should fix your problem