Sign in to follow this  
Followers 0
benbrad

CJ1M password protection

8 posts in this topic

I've been asked today to lock a CJ1M 23 ready for despach to an ex-competitor. Our company is now on friendly terms with our Russian counterparts and the powers that be have agreed to send them some of our machines on licence. I've had to build an encrypted key into the code so that every month (provided we're still on good terms with them) they can enter a new key and the machine will run for another month. I've never used the password facility as everything here is "in-house", and I'm a bit concerned as to how easy it might be to break into the code and disable the licence section. Does anybody have any idea as to how hard this is to do? Is there a way of automatically erasing all the code should someone illegally attempt to access it? Thanks in advance benbrad

Share this post


Link to post
Share on other sites
Hi Ben, Here are some pages from the programming manual about protection. Never used protection myself. I recall the CPU locks itself after 5 false password attempts but I don't know if this is also the case with CJ1M. Alternatively there is a function that replaces complete program with a pre stored program on a memory card. protection.pdf

Share this post


Link to post
Share on other sites
PDL, I believe there is an misprint in Note 2 of your attached pdf file. The word 'cannot' should be 'can' instead.

Share this post


Link to post
Share on other sites
Thanks for pointing that out ECSI, it's extracted from the CJ/CS series programming manual.

Share this post


Link to post
Share on other sites
Hello benbrad, If you search the forum (and not just this one), you'll find that people have quite a lot of trouble 'cracking' PLC password protection. The CS / CJ series use an 8 digit alpha-numeric password, so that leaves quite a lot of possible combinations! And you can password protect individual tasks within the PLC as well, making it 'doubly' difficult to get at your program. I'm not saying that it is impossible to crack the password protection (nothing is totally failsafe), but it would require either real specialist knowledge of the PLC's internal memory set-up, or total determination / luck to by-pass it. Hope this helps quell any concerns you may have. Regards anonymous

Share this post


Link to post
Share on other sites
Thanks all for your input. Read the manual now, absorbed some of it. What happens after too many wrong password entries? It doesn't have to go off to Omron for repair, does it?

Share this post


Link to post
Share on other sites
Hello benbrad, I think this may confound a few people, but no, as far as I am aware, the idea of 'x' number of tries to release the password before it locks you out completely is a total myth. Just to make sure, I've just tried 20 or so incorrect attempts on a CJ1M - could still release it using the correct password. Regards anonymous

Share this post


Link to post
Share on other sites
Cheers anonymous I'd have tried that myself but for fear of doing something I would later regret. Ben

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0