What is OB2- OB9 ?

[douyi 0]

What is OB2 - OB9 ? Can I use them? How ? by the way, I can only find s5time, how can I use IEC timer? - in LAD ? Thanks in advance.

[RMA 0]

Unless they exist in 400 series CPUs, which I've never used, OB2 - OB9 don't exist, not on my copy of Step7 V5.3, anyway. You'll find the IEC Timers in the Standard Library. You can access this from the Simatic manger via: File -> Open then Libraries -> Standard Library For reasons best know to Siemens, the Timers are not in the IEC Functions sub-directory, but in System Function Blocks! SFB3 - SFB5 are what you're looking for. You can use them directly in LAD OK. Edited 5 Aug 2005 by RMA

[douyi 0]

Actually, what I did is insert a new object as an "Organization Block", and type in OB2 in the pop-up dialog and Simatic Manager generated it, I can open it, do whatever I want to do with it, but I don't know how the processor will do with that and I can't find any help from manuals or help files. As a professional, maybe you guys know that. Thanks.