Allen Bradley SLC 5/03 strange fault state - I need help with the LED diagnostics

[Oleksandr_Husyev]

Hello everybody!

One our customer from the far placed site sent us a video with the very strange behavior of SLC 5/03.

Link on this video:
https://drive.google.com/file/d/0B1cF3Af-O4PHaEFYVXVHT21KN00/view

After power on LEDs on the SLC CPU module every two seconds cyclically light in the following sequence:

1. FAULT, FORCE, DH485 - all are lighting for 1 second

then after 1 second:

2. FAULT, BATT, FORCE, DH485, RS232 - all are lighting for 1 second

then after 1 second everything repeats once again.

The customer also tried to reset this fault with key switch (RUN -> PROG -> RUN) but this had no effect. Also he doesn't have any software or cable to connect to the PLC and check out fault information with RSLogix. This is a stand alone far placed production line so we can't get there immediately.

What the kind of fault could it be?

Best regards, Oleksandr.

 

[geniusintraining]

Any chance they moved the jumper for flashing the firmware? have them take a picture of the jumper and make sure its in the protect position

 

[Mickey]

See pdf for trouble shooting guide.

 

[Oleksandr_Husyev]

Guys!!! Thank you very much for the fast replies!!!

As far as I understand from Troubleshooting info that the CPU has at least fatal hardware error (the first state when LEDs FAULT, FORCE and DH485 are lighting).

But the second state (when all LEDs are lighting: FAULT, BATT, FORCE, DH485 and RS232) does not present in the faults description table.
In the description there is the state with LEDs FAULT, BATT, FORCE, DH-485 but without RS232 (The operating system is missing or has been corrupted.)

What the state with all LEDs could be meant?

Best regards, Oleksandr.

 

[Mad_Poet]

Dear Oleksandr,
I don't suppose there is any chance that the power is coming and going on the PLC is there?

MadPoet.

 

[keithkyll]

Power supply has become marginal. Powering up, then failing under load. Bad capacitors. Replace.

 

[Geospark]

Hi,

First...

Just one small difference to point out in what you have described as being the sequence and what can be clearly seen in the video...

...After power on LEDs on the SLC CPU module every two seconds cyclically light in the following sequence:

1. FAULT, FORCE, DH485 - all are lighting for 1 second

then after 1 second:

2. FAULT, BATT, FORCE, DH485, RS232 - all are lighting for 1 second

then after 1 second everything repeats once again.

The FLT LED is solid ON during the entire sequence in the video. It is not flashing with the other LED indicators.

These unusual SLC LED indicator patterns are indicative of an internal hardware failure during processor boot. The particular LED indicator sequence you have described is identical to the one described in the following AB technote article...

14988 - SLC 500: LEDs flashing in unusual sequence that is not shown in the manual
Access Level: TechConnect

Note again how the FLT LED is mentioned as being solid ON. This condition is a hard fault state. While the FLT LED is solid ON, the communications ports are in a lock down state and will be incommunicado. You must get the FLT LED flashing again to reestablish any communications.

Although the technote describes such a sequence for an SLC 5/04 (CH1 DH+), it is identical when experienced with an SLC 5/03 (CH1 DH-485). The same pattern is witnessed on the DH-485 LED as is witnessed on the DH+ LED.

During this fault the program will have been cleared from the processor's memory. Do you/they have a backup copy of the program?

To recovery from this faulted state you can attempt the processor factory default procedure. If you cannot access the technote article, the following is the procedure which may be performed...

Disconnect the battery from the back of the processor.

Locate the VBB and GND points on the back of the processor PCB.

Short these points together for roughly 90 seconds.

When finished, double check the 'J4' jumper is in the 'Protect' position on the back of the processor (pins 1 and 2).

Reconnect the battery, install the processor, and power up the chassis.

I would also recommend removing any I/O modules from the chassis and just power up with the processor initially.

If this procedure has been successful then the FLT LED indicator should be flashing RED. All other LED indicators should remain OFF.

If so, the processor boot failure has been recovered and the processor is ready to download a program to again.

If I/O modules were removed, then I would start refitting them one by one, powering down before inserting each module and checking as you go that the processor FLT LED remains flashing and does not hard fault again.

Even if there is someone onsite that can perform such procedures, that may only recover the processor ready for a program download. But it would at least tell you that the processor is reusable. As they do not have the programming software to download a backup of the program, if one exists, then you, or someone who does have the programming software, would still have to visit the site to perform the program download.

It is also entirely possible that the factory default procedure will not work and the processor may be permanently faulted.

Either way, I'm sorry to say that I cannot give you a solution that they can perform to get going again, quickly.

Regards,
George

 

[Oleksandr_Husyev]

Hello!
Dear Geospark! Thank you very much for such fast and helpful answer
I send all these instructions to the site guys and they would try to reset CPU to the factory settings and may be FAULT LED will become flashing state. If yes we are going to continue with them via TeamViewer. So now I am waiting for their results.

Best regards, Oleksandr.

 

[PLCnovice61]

If GS says it's dead and gives a concise reason for it being dead, maybe it is dead.

UNLESS it's not dead.

Com on Daba, this is people up north being more knowledgeable, surely not.

just being helpful, ha ha.
GS as per usual a very in depth and likely the right answer.
But man you must like typing (or coping).
Regards your loving servant.
KD

I blame Guantuer for starting this attitude which l like.

 

[ASF]

I blame Guantuer for starting this attitude which l like.

You mean the "getting drunk/high then posting a series of incoherent and borderline abusive messages" attitude?

 

[dmargineau]

Note qualifier in his/her username...I believe it is also true regarding specific substances ingesting...It must be weather related...It's winter there after-all...

 

[geniusintraining]

You mean the "getting drunk/high then posting a series of incoherent and borderline abusive messages" attitude?