Logix 5000 Technician-Level Access - What Are The Best Practices?

Hi all,
We are looking for the best practices when it comes to maintenance technicians having online access to our PLC's. We would like to give our technicians the ability to go online with a PLC for troubleshooting purposes but not allow them to make changes. I would love to know how everyone is handling this in their facilities.

Thanks

Better HMI design.

It will depend on the platforms used I suppose, before I retired, I was the only one that had access for over 15 years at the last place I worked, I was on call 24/7 (providing I was available even when I was on holiday I had remote access), however, there were a couple of young engineers who I felt could with some training use a laptop to go on-line for troubleshooting purposes, I would keep the "Engineers" laptop up todate with the source files these were all password protected so could not be modified only viewed & on-line monitoring, the PLC's were all PW protected for view only, all those approved were given training, the laptop had to be signed for from the stores. The HMI's were a different problem, fortunately most were the Beijers E series, you could load the project that had been compiled (DAT file) so again, the stores kept all the HMI files each one on a seperate USB stick (yes a lot of sticks but for the little cost it was worth it), had to be signed out & back in, they had no access to the IDE so could only load the file onto an existing or new HMI.

When I worked in a production support role, we had one or two controls technicians (me being one of them) that worked Mon-Fri and handled most of these things. We were a 24/7 operation, so during nights and weekends the lead technician for that shift (me at one point) was the one responsible for going online with equipment when necessary. Some didn't mind, some didn't want to be the one to break the machine even worse and would keep equipment down until a controls tech could be called in. Generally we didn't let non-lead technicians on crews access the laptops or the programming except for training, and even then the lead technician on duty or a controls technician was supervising, took backups, etc.

That being said, as I'm sure you will be told repeatedly, the best programming is that which rarely if ever requires a connection to troubleshoot. I may sound like a broken record, but well-designed code, a healthy alarm structure and solid HMI design goes a long way. Just my $0.02.

Well designed code still does not work, got called by the Engineering manager, 5 engineers had been working on a machine for about 7 hours still no luck, so I popped down looked at the alarm screen "LOW AIR PRESSURE", Turned it up & there were a few red faces. You can put every conceivable system in place & they still mangage to miss it.

The issue there is the expectation... when they expect to have to log into the PLC to troubleshoot a fault, they're already wrong. If that is not there, they'll be forced to start from scratch.

I had similar where they never even opened the control panel to look for tripped breakers or broken fuses.