Anyone out there with A-B SLC 500 experience?

[ralph@nes]

Help!

I've got an old Heald grinder that's been set up with one of these. It's worked flawlessly for quite some time, we powered it up this morning and got a 'No active nodes found on the network' alarm. I'm rather confused as to what network it refers to, as this thing is ancient. Is this something anyone has encountered before and can you point me in the right direction as to where to start looking?

I've got a decent pile of paperwork that came with this thing... Reams and reams of printouts and whatnot. I guess I'd just like to know what the heck went wrong.

Thanks in advance, folks.

[Al_The_Man]

It has been a while since I programmed a SLC500, What do the status LED's show on the fron of the CPU?
It sounds like you may have a network setup it uses a DH-485 communication port for things like remote I/O modules etc, if you do then it may have lost communication for some reason.
Al.

[cp8071]

You might try these PLC forums:
http://www.plctalk.net/qanda/forumdisplay.php?f=2
http://forums.mrplc.com/

But be prepared to give full part numbers and clear idea of the whole system!

Where did you see this error? "DH485" is an A-B protocol for having many devices share a serial network. Each device is identified by a Node Number. If you're just trying to connect with the programming software then it could be using this protocol and the software can't detect the PLC.

[ralph@nes]

I'm not trying to connect with any sort of software, this error comes up on the front display when we start the machine up.

Al, the two LED's that indicate network connectivity are blinking, the DH+ and RS232 LEDs that is.

I think I'm starting to understand that the network is this internal stuff... I guess I'm just at a loss as to how to proceed.

[Al_The_Man]

Do you have a cable plugged into the LAN socket in the front, CAT5 etc cable?
If so what is on the other end?
Al.

[cp8071]

What is the "front display" is this a PanelView? 2711-xxx part number?

My guess is that your SLC lost it's program because of a dead battery, now the panelview can't communicate with the PLC.

DH+ so it's a SLC 5/04? What is the status of the RUN, FLT, BATT lights?

[ralph@nes]

No, there's nothing hooked to this that wasn't there yesterday or ever. I don't even see a place for a Cat5 cable.

For what it's worth:

SLC 5/03 CPU module

1 SLC servo module with Ultra 3000 drive
4 input DC-SINK modules
2 output DC-source modules
1 output Relay module

Panelview 550 front pane.

Error is 612-No active nodes found on network

And the led is DH-485, along with RS232 blinking
Run light is on
FLT, Force, and Batt LED's are all off.

[cp8071]

SLC 5/03 is DH485, not DH+. Open the front cover just under the LEDs, should pull open and hindge to the right. Now you have two communication ports. The top is DH485 that looks like an Ethernet port, it is not, do not plug Ethernet into this! The bottom is an RS-232 port that could be configured several different ways. Tell us what is connected to these ports. Also what is connected to the back of the PanelView. The PanelView can't see the PLC, but it seems they both have good configurations. If you have another device in the cables between them then tell us about that also. Could have something called an AIC module.

If it's nothing obvious then you'll have to find someone local with RSLogix500 and PanelBuilder software ... it's $$$

[ralph@nes]

Looks like I've just got RS232 on the 5/03 connected directly to the panelview 550 (2711-K5A9). I can't 'see' any device in between the two. If there was a device, what would it look like and where would it fall?

[cp8071]

You've got a good start on everything that you're going to need. But based on the below manual and error description, you're gonna have to have someone go online with the PLC and determine what's wrong. Need to find someone with RSLogix500 and the correct firmware rev that matchs your PLC (This info is found on a sticker on side of the CPU card.) Need to find a system integrator or programmer in your area. Do you have info on who originally programmed this machine? Be aware that these devices can be password protected to prevent you from getting into them.


http://literature.rockwellautomation...m014_-en-p.pdf

Error Number
612

Terminal Messages
No active node(s) found on network

Type
Comm Status

Meaning
Tag or address does not exist or is the wrong data type.

Recommended Action
Check tag address.
Check for data type mismatch.

[ralph@nes]

Apparently I'm going to need some sort of 1747 module to talk to this thing. I spoke with a AB tech that said it could be as simple as an accidentally changed baud rate, or it could be a failing PV.

Question: Is the 'program' stored in the 5/03 or the PV?

[cp8071]

Both! They each have seperate programming softwares and seperate project files.