AC500-S Saftey Processor loses all programming ... how is it possible?
First let me explain, I am the PM on a project .. not a programmer myself.
I was contacted by one of our most experienced programmers - that it indicated that we may need another spare AC500-S sent up to be pre-programmed. in the event that they had to use there back up. (any extremely techincal information will be passed directly to them, all other i might be able to cope..lol)
The main Safety Processor an AC500-s lost the entire programming (code) after the system was shut down last night in a completely brand new system still undergoing commissioning.
*The power down sequence was followed.
Upon arrival at the site this morning, the commission team powered up the system, it was found that the processor had no code..hmmm
*NO FAULT INDICATORS*
** yet they were able to restore the code into that processor.. and everything appears to be fine !!!
over the last 10 weeks this processor has worked without issue..
What concerns me is how a SAFETY PLC can just randomly lose its programming and no faults be recorded.
no other devices or PLC's were affected
*The Processor P/S is 24vdc Meanwell which we have used in hundreds of other systems.
*The whole panel has an incoming 415vac 3ph for the ACS800 drive.
I am hoping that some one else has experienced similar and has an answer to prevent a re-occurrence after our team has left.
Please help .. and give us a few possibilities to look into!
As this is a major concern for safety related projects in remote regions
The AC500 PLC's store their program on an SD card. The first thing to do is check that the guys on site have actually followed all the correct procedures for creating a Boot project on the SD card and tested this successfully.
AC500 PLC's do not "like" third party SD cards. While you can often get away with using a third party card OF THE CORRECT MEMORY SIZE, ( You cannot format a large SD card to a smaller memory size) In a safety application it is important that you use an officially supported SD card from ABB.
See attached manual section 2.9 ....
2.9 AC500-S restart behavior
When SM560-S / SM560-S-FD-1 / SM560-S-FD-4 safety CPU is restarted using poweringoff/on, the previously saved error information is lost.