AB 1747-L551 Processor

[marc.hickling]

Hey there wondering if anyone can help?

I have 6x 1747-L551 processors and about a month ago I connected to them all by serial port and null modem cable and got comms. I configured the processors to be network controlled giving them an ip address and then stored them for a month or so.

Now when I go to turn them back on I get the boot sequence of:

Fault light flash
All lights flash
Fault light flash
No lights displayed

then after around 2 minutes I get the ENET light flash a few times and then go out. I find when I plug my processors into an active network card I can get the ENET light to stay on but cannot see it in BOOTP and the lights aren't flashing. (I can't remember the IP's anyway).

I have tried communicating with the units via the same serial cable as before and still can't get anywhere so now I can't control the processors at all. I have also tried pulling the battery and shorting the cap to reset the unit's memory but this doesn't seem to help either.

Any suggestions?

 

[daba]

BOOTP will only show Ethernet adapter ports that are not configured with an IP address.

Your post is confusing... "I configured the processors to be network controlled giving them an ip address".... do you mean that they are configured to use BOOTP to assign addresses ?

Or have you set the IPs and sent "Disable BOOTP" command via the BOOTP program ?... "(I can't remember the IP's anyway)."


If you reset the module by shorting the cap (not the recommended way, incidentally, you should short out the two copper lands labelled Vbb and GND), you perform a "factory reset", and will lose all ethernet comms settings, and restore the serial port to "default" settings.

Using auto-configure in your RSLinx DF-1 driver set-up is the easiest way to get comms going again. Then you can reconfigure the IP ports.

 

[marc.hickling]

thanks for the help!

some replies to your questions:

Your post is confusing... "I configured the processors to be network controlled giving them an ip address".... do you mean that they are configured to use BOOTP to assign addresses ?

So another guy configured them and gave them an IP i believe he did this through serial cable and RSlogix500

Or have you set the IPs and sent "Disable BOOTP" command via the BOOTP program ?... "(I can't remember the IP's anyway)."


If you reset the module by shorting the cap (not the recommended way, incidentally, you should short out the two copper lands labelled Vbb and GND), you perform a "factory reset", and will lose all ethernet comms settings, and restore the serial port to "default" settings.

Using auto-configure in your RSLinx DF-1 driver set-up is the easiest way to get comms going again. Then you can reconfigure the IP ports.

I've reset the unit a tonne of times including the way you suggest (on the copper lands) and the unit still doesn't communicate on serial through autoconfigure on RSLinx DF-1.

If there a chance that the serial port is disabled in the software? I.E can it be turned off or will it always work?

I don't seem to be able to get network comms either, any suggestions?

here's a video of it booting up: https://www.youtube.com/watch?v=2FNouo8RHkQ

thanks

 

[marc.hickling]

thanks for the help!

some replies to your questions:

Your post is confusing... "I configured the processors to be network controlled giving them an ip address".... do you mean that they are configured to use BOOTP to assign addresses ?

So another guy configured them and gave them an IP i believe he did this through serial cable and RSlogix500

Or have you set the IPs and sent "Disable BOOTP" command via the BOOTP program ?... "(I can't remember the IP's anyway)."


If you reset the module by shorting the cap (not the recommended way, incidentally, you should short out the two copper lands labelled Vbb and GND), you perform a "factory reset", and will lose all ethernet comms settings, and restore the serial port to "default" settings.

Using auto-configure in your RSLinx DF-1 driver set-up is the easiest way to get comms going again. Then you can reconfigure the IP ports.

I've reset the unit a tonne of times including the way you suggest (on the copper lands) and the unit still doesn't communicate on serial through autoconfigure on RSLinx DF-1.

If there a chance that the serial port is disabled in the software? I.E can it be turned off or will it always work?

I don't seem to be able to get network comms either, any suggestions?

here's a video of it booting up: https://www.youtube.com/watch?v=2FNouo8RHkQ

thanks

 

[daba]

After a "factory reset", the serial port will be enabled for DF-1 protocol.

You should be able to communicate with it via your standard 17XX-CP3 cable. Has this cable been verified on another device ? Do you have another cable ? Can you verify your laptop serial port is functioning ?

If RSLinx Auto-configure does not work with a known good cable, and your laptop serial port is ok, then it looks as though your module is fried...

EDIT : Your Youtube video is marked as "Private", and I can't access it.

 

[Geospark]

Common denominator?

Welcome to the Forum!

Daba,

I'm more curious about the LEDs. We don't know what they're doing after attempting to default. This is important to know before moving on to the comms.


Before attempting to establish communications can you confirm to us that you have successfully defaulted the processor(s)...

What are the LEDs doing after you attempt a default?

Are you still getting the same LED sequence as before?

If the default procedure is successful then you should have just a flashing FLT LED.

Only then can you proceed to attempt to establish communications.

If the LED sequence is still the same after attempting to default then make sure you are shorting the pins long enough to discharge the capacitor. The recommended duration is 90 seconds.

But something else worth noting here...

I can perhaps understand one previously working processor suddenly displaying this LED sequence after power up from a short storage period, but six?

Can you confirm that by "them" you mean all six processors display the same LED sequence at power up?

If you cannot get any of them to default successfully then I would be more inclined to think that there is a common denominator at fault here, more so than all six processors are actually faulty.

Have they each got their own chassis and power supply or are you powering them all up one by one in the same chassis, such as a test chassis or spare chassis and power supply?

Either way, make sure that any power supply being used is set to the correct voltage via its jumper (120VAC / 240VAC). The factory default is 240VAC, which can catch a lot of folks out using 120VAC.

The voltage jumper can be tricky. Even if you power on successfully, on a 120VAC line supply, with the jumper incorrectly set to 240VAC, the processor and I/O can all appear to work fine, but the comms can act up. Or from time to time the processor might clear its memory.

For a 240VAC line supply, with the jumper incorrectly set to 120VAC, the power supply usually won't power on at all and so the problem is somewhat more obvious.

The current LED status and voltage jumper setting are just some basics I would suggest to rule out before moving on.

Regards,
George