Defaulting Memory Card to fix connection issue

[Awloescher 2]

Newer automation tech here...still taking classes and learning on the job as well.  We've had trouble connecting with our SLC 5/04's.  We get the message "failure to find baud and parity rate...check cables"...or something to that effect.  A few times we've somehow got it to connect.  Cables are new, using RXLinx Lite to connect, USB 1747 CP3 to 1747 CP3 SER A to connect to RS232 port on SLC 5/04.  Autoconfigure just won't communicate...trying to communicate with RS232 DF-1 Driver.  SLC has no fault, no battery low indicator.  I've experienced this twice now on two different SLC's.  One time I was able to connect, but I can't figure out how.  The maintenance guy told me I need to default the memory card, which as I understand it involves shutting off the power to the unit, pulling the memory card, then reinserting it?  Is this the "go-to fix" or something?

Thanks in advance for the help.

Andrew 

[Awloescher 2]

[pcmccartney1 139]

Is it possible the RS2322 Port of the SLC is configured to talk to something other device and therefore not talking DF1?

Presumably, your laptop doesn't have a serial port.  More than likely a USB to serial converter is being used.  Make sure the converter and the USB port are correct and that no other device in your PC is "stomping" on that port.

[Joe E. 244]

Also, are you using a virtual machine? If so, try connecting the USB-Serial adapter directly to the VM instead of the host. We've had trouble with the physical COM port of the host not translating predictably to the VM.

[pcmccartney1 139]

From a VM standpoint, usually you would install the USB Driver in the base OS and then configure your VM to pass it thru or be used within the VM.

Generally, the Autoconfig  should work if everything is able to talk.

Back on the other subject, are you sure the RS232 port is not setup to talk to some other device?  In your picture, I see blue hose and a serial port are occupied.  Did you pull a cable off that port before plugging in your cable to the PC?

Also, the keyswtich is in RUN rather than RUN-REMOTE, not sure that this would affect your ability to connect.  It would prevent you from doing anything other than reading the program.  Try turning the keyswitch to PROG, this should stop the program execution and then see if you can connect via RSLinx. DO NOT TRY THIS IF THE PROCESS IS ACTIVE.

Edited 13 Feb 2019 by pcmccartney1

[Awloescher 2]

 

1 hour ago, pcmccartney1 said:

Is it possible the RS2322 Port of the SLC is configured to talk to something other device and therefore not talking DF1?

Presumably, your laptop doesn't have a serial port.  More than likely a USB to serial converter is being used.  Make sure the converter and the USB port are correct and that no other device in your PC is "stomping" on that port.

It is configured to talk to a scale, which according to the PLC program is Ch.O "user mode", not "system mode", which is an ASCII driver.  Is there a driver when configuring in RSLinx specifically for talking to an ASCII driver? (see attached pic). I did pull the RS232 cable that connects the SLC to the scale.  The blue cable is for DH+ communication with the PanelView 550.  I've tried connecting to it with the switch in Run and in Program.

 

38 minutes ago, Joe E. said:

Also, are you using a virtual machine? If so, try connecting the USB-Serial adapter directly to the VM instead of the host. We've had trouble with the physical COM port of the host not translating predictably to the VM.

Thanks for the reply Joe...yes we are using a virtual machine, and yes we connect through the VM...com port is completely different and won't recognize the port if we go through the COM port through the host.

[Awloescher 2]

So what I've gained from digging for information is that I can't talk to an ASCII driver with RS232.  So I assume my only option then is to default the memory card and reset/ download the program again.  Is that correct?

[pcmccartney1 139]

There is a way to "blank" the memory or therefore the program by removing the CPU from the rack and shorting out two pins.  This assumes that you already have the program backed up offline on your PC.

Currently you have no way of getting online and viewing, debugging or modifying code.

Not sure, others here are more expert than I, but you might be able to to talk to it from the DH+.  But I think you need another piece of hardware to attach and a different driver.  It's something like the USB/Serial Adapter, but for DH+.

Did a quick google search and found the 1784-U2DHP Cable and Adapter.  Looks very expensive.  You would need to use the specific driver called 1784-U2DHP for DH+ devices.

Also saw EtherNet to DH+ Adapter, not any cheaper.

Scratch the EtherNet idea.  Looking around I find the old NET-ENI but it talks to the RS232 port.  Most everyone's suggestion is upgrading the procewss to the 5/05 with built in EtherNet.

Edited 13 Feb 2019 by pcmccartney1

[Awloescher 2]

I also saw the option of using a serial port splitter 1747-DSP1/2...it's hard to tell if it would support talking to the ASCII scale.  And it's also quite expensive.  Seems like any option is fairly expensive, since I can't plug into the DH+ or RS232 port and still debug/go online while process is running. It's not a large enough problem where the company is going to spend that kind of money to upgrade the equipment, so I'm most likely going to have to go with "pull the memory card and reset it", since we do have the existing program on file...unless anyone else has other ideas.  Thanks for the help and knowledge gained :)

[Joe E. 244]

If the RS232/USB adapter is connected to the VM using the "removable devices" menu, go to Device Manager and double-check which COM port number it was assigned. It may not be the same port number it got last time, especially if it's plugged into a different physical USB port.

But, from what you said, it's configured for an ASCII protocol that RSLinx can't use (if your research is right, I haven't confirmed that).

Are you still using that scale? If so, you're not going to get very far with setting the COMMS to default. Once you download the program back to the PLC to get online, the port will revert and you'll be dumped offline. Since you're using the COM port for a scale, and DH+ to an HMI, you won't be able to use a 5/05 since the 5/05 doesn't have a DH+ port. Your best bet right now is probably to connect to it via DH+, which won't be cheap. Actually, a better bet is to replace the 5/04 with a 5/05 and the HMI with one that supports Ethernet. That may not be in your budget, though.

We've had very bad results from the AB U2DHP modules. They are very expensive and just stop working without having been "abused". For systems where we must use DH+, we have a couple of Prosoft Ethernet to DH+ modules (AN-X2-AB-DHRIO). They're pricey, and need an external power supply, but they've been flawless.

We used to have a ControlLogix chassis on our computer cart with a 1756-ENBT module in one slot and a 1756-DHRIO in another. That worked well too but was a little cumbersome and would only be cost effective if you had those components lying around unused.

Our standby for aftermarket cables has been these guys:

https://www.plccable.com/allen-bradley-1784-u2dhp-alternative-usb-to-data-highway-plus-dh-anc-120e/

We haven't tried their DH+/USB system since we already have the Prosoft system working, but it is cheaper than the AB version, at least for us with our AB pricing.

The SLC 5/04 has a round mini-DIN port and the 3-pin phoenix connector on the front. Both are the same DH+ port, so you can get your gateway device connected at the same time as the HMI.

 

Edited 14 Feb 2019 by Joe E.
Stupid typos.....