Micrologix 1200 , faulting

First part of this week we had a lightning induced momentary
power failure. An A-B Micrologix 1200 PLC suddenly faulted,
indicating a application program fault. Subsequently reloaded
program, and off we went, with the 1200 happy, and all lights
blinking green...
Operated the system, mainly in standby mode for the past 14-16
hours, and when the operator pressed a series of command buttons,
oops, the 1200 faulted out again, same application fault. System
trouble shot, and no electrical problem found, other than the
Micrologix 1200, stopped and blinking the red fault light.

Has anybody noted this controller to be extra sensitive to spikes, or noise, or perhaps the big jolt at the firts part of the week blew out some noise protection, or spike protection in
this controller, which will result in replaceing the controller.

This controller is operating a number of solinoid valves on a
hydraulic system, and I have not found any snubbers or spike
protection to protect the outputs from solinoid release spiking,
which could also capacitivly couple to the PLC input power.

This system has run for a number of years in an R&D mode, and
now going into a production mode, is giving us problems.

Suggestions and ideas ????

Thanks
Tim Jones
Elan Motorsport Technologies Inc.
Georgia

I have an old L40 fixed SLC that got hit and stopped working so I replaced it. I found later that it would come on but got hot and faulted, I found a bad component on board. I have it working but just use it for a test system.

If the ML1200 is a 120vac model you may want put surge suppression on the incoming power. Noise/harmonics especially if AC drives/inverters are used can create issues. Bad ground loop can cause problems.

If it keeps faulting dont try to have one of those 3rd party repair services fix it, cheaper in the long run to go thru AB and do a replacement exchange. At least that has been my experience.

Unsuppressed inductive loads are always Suspect #1 in MicroLogix controller faults. Get some R/C snubbers (or diodes, if they're DC) onto those solenoids and I'll bet your problems go away.

There's also my #2 recommendation for MicroLogix: The Big Fat Green Wire. Use a healthy-sized ground wire on the MicroLogix and it become far less sensitive to noise.

Thanks guys, I am hearing what i suspected I would hear, seems like when
we go for cramming more into a smaller box, the spike and noise problems
multiply logritmithicaly, due to close proximity of termainals and components.
have already orddr a corcom filter for the input, and a dozen big blue
snubbers for all the valve solinoids... Guys who designed this thing, say, Oh we never have a problem with these units.... Right.

Thanks again.

TJ

Suggestion Required, New Member don't ignore...

Please do the needful.
Looking ahead for a good response...


Regards,
Haroon

haron110 said:

Please do the needful.
Looking ahead for a good response...


Regards,
Haroon

Click to expand...

Reread post #2 and #3. Carefully.

Thanks Mickey I will go though this today, and see how much happiness i get @ ur qutation...

Regards,

Hi there! I drived 100kms in desert far away to go through ur suggestion, I had checked all PLC n panels ground loop... It is fine, I hope solinoid(s) n relay(s) will be good, but, still PLS's red fault light has not gone...
Do it need re-programming or any other???? plz am expecting same response from you n others....

Regards,

haron110 said:

Hi there! I drived 100kms in desert far away to go through ur suggestion, I had checked all PLC n panels ground loop... It is fine, I hope solinoid(s) n relay(s) will be good, but, still PLS's red fault light has not gone...
Do it need re-programming or any other???? plz am expecting same response from you n others....

Regards,

Click to expand...

You will need connect to the PLC with a Laptop running RSLogix500 and RSLinx to be able reset the fault and put the PLC back into Run mode.

You may try and contact manufacturer to see if they can come and reset the fault for you if you do not have the required software.

Thankx Swimmy67! It was all helpful...

Regards,
Haroon

Hello,I have tried all advised.Now the red LED is no more ON Solid,its now flashing and the COMM 0 LED will be coming ON intermittently.Still not been able to establish connection.I inserted the memory module to check still the same.I want to assume the program as wiped off or corrupt.I want to start a new project on my PC,Please give me the steps to follow then when i finish,I will upload for u guys to ascertain then we download to see by then it will communicate

Thanks for all ur supports so far

Hello,I have tried all advised.Now the red LED is no more ON Solid,its now flashing and the COMM 0 LED will be coming ON intermittently.Still not been able to establish connection.I inserted the memory module to check still the same.I want to assume the program as wiped off or corrupt.I want to start a new project on my PC,Please give me the steps to follow then when i finish,I will upload for u guys to ascertain then we download to see by then it will communicate.Thanks for useful supports.CAN ANYONE HELP ME

sheriffinst said:

Hello,I have tried all advised.Now the red LED is no more ON Solid,its now flashing and the COMM 0 LED will be coming ON intermittently.Still not been able to establish connection.I inserted the memory module to check still the same.I want to assume the program as wiped off or corrupt.I want to start a new project on my PC,Please give me the steps to follow then when i finish,I will upload for u guys to ascertain then we download to see by then it will communicate

Click to expand...

You should re-post this in the thread you started, it makes it easier to follow.
Link to your other thread:
http://www.plctalk.net/qanda/showthread.php?t=69928