Plc with password protection.

Hi Everyone!

an equipment was relocated from another country to my country and one of the machine has a problem and I need to check the plc program but the plc(MICROLOGIX) request a password.Does it exist a way to access to a plc program that has a password protection?Please advise.


Thanks.

The builders of the machinery installed the password for what they considered to be a valid reason. You should contact them.

the programmer has gone and can not be contacted.

You can contact Allen-Bradley tech support and they may be able to help you.

What makes you think the problem is in the PLC program? The machine worked in the past. Now it doesn't. Do you think the program wore out or got bent out of alignment?

the programmer has gone and can not be contacted.

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If I had a dollar for every time I've heard that one...

If you don't like the way the current program controls the machine, there is nothing stopping you from clearing the memory and starting over. But the original programmer chose to prevent others from modifying his work. He had what he considered to be valid reasons for doing so. I'm not willing to substitute my judgement for his, so even if I knew a backdoor password, I wouldn't disclose it.

If you don't like passwords, don't buy equipment from people who apply them. Either that or make sure you get the password when you buy the equipment.

I did not purchased the machine,also it is an old equipment and all I want is to make it work,it would be easier for me just to say I do not have the password wash my hands and sit down.

I agree with Steve Bailey. As programmers we cannot undermine each others attempts to protect our work for whatever reason it may be. Possibly he protected it to ensure he would get paid for his work and maybe he never got paid. Maybe he did it because he want to protect his intellectual property. Maybe he doesn't want anyone messing with his program. There is usually a reason for password protecting a program.

I would suggest you get to the root of the problem or pay to have the system programmed from scratch. I know its not what you want to hear but its what I'd tell one of my customers if they asked me to circumvent someone's password.

From what I have experienced in the past, unless you have a machine with an imbedded program that will cure cancer or figure out the female mind, there is no reason to password protect it. Those that do only have one goal in mind , force the end user to deal with the programmer.

Steve Bailey said:

What makes you think the problem is in the PLC program? The machine worked in the past. Now it doesn't. Do you think the program wore out or got bent out of alignment?


If I had a dollar for every time I've heard that one...

If you don't like the way the current program controls the machine, there is nothing stopping you from clearing the memory and starting over. But the original programmer chose to prevent others from modifying his work. He had what he considered to be valid reasons for doing so. I'm not willing to substitute my judgement for his, so even if I knew a backdoor password, I wouldn't disclose it.

If you don't like passwords, don't buy equipment from people who apply them. Either that or make sure you get the password when you buy the equipment.

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I used to work for a machine builder. They would protect programs "So they could support them" = so we can force you to call one of our engineers in!

Now I work for an end user and would NEVER buy anything protected. This has been covered before - how *****d of would yu be if you tried to pull the hood on your car and the dash flashed "Enter your password or contact your Ford dealer"?

Call Rockwell Tech support.. sometime back there was a master password available for some AB PLC models. If you tell them the model and approx manufacturing year, they will be able to help you.

Real Espana said:

I did not purchased the machine,..

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So, its not your problem...It is the problem of the person who bought the machine...

I hate to see people buy machines that have no idea on how they work, or what is involved in maintaining them - they end up leaving people like you and me in a bad position

Real Espana said:

it would be easier for me just to say I do not have the password wash my hands and sit down.

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This is what you might have to do to get the message across to the "machine buyer" - when they buy machines in future they might learn to take care of all of the details, such as software passwords - or they can pay $$ to re-engineer the machine with new software.


Rant finished

There are both pros and cons with password protecting a person intellectual property. I know I have run into this a few times in my career.

One such time was with a GE 90/30. While I would have loved to go back to the engineer or the company that built the machine there was no such way to do so being as the company went bankrupt before they even ever completed the project. What really sucked was the fact that they left no note, no schematic, no nothing. So I ended up having to trace each wire, make a schematic, then rewrote the program from scratch. Not an easy task but it was rewarding in the end to see the machine function correctly.

And I do sometimes use passwords, but I mainly use them in higher ended routines that are critical. I do this to ensure that no one can just go in and change things in that area. However that being said I always leave the passwords at the machine if you know where to look. And I give it to mgmt as well.

Sometimes there is justification to use tools like passwords to prevent user self-service of a machine; preserving a warranty, protecting a lease agreement, and especially limiting liability.

Rockwell Automation's Technical Support group can help you bypass the password on a MicroLogix 1000 controller if you can provide commercial documentation that proves that you own the intellectual property within the controller. It's not cheap, but it can be done.

One doesn't ask for a password or assembler code for a microwave oven PIC microcontroller.....

Just because a machine has a PLC doesn't mean the program should be tampered with. OEM's build machines for a dedicated purpose and end user's modifying code should be doing it only after signing a full disclaimer releasing OEM from all liability.

And no matter how complicated the machine, if the end user programmer can't watch the machine and reprogram the code from scratch by watching it work and mapping IO they shouldn't be plugging in. Which p/w or not they are going to effectively be doing as once plugged in won't have any documentation and they will need to build the offline file so they can note what the i/o are doing in the first place.

Maybe he just wants to monitor the program for troubleshooting?