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dcalderonv
Hi,

We are working with some motion control instructions that we have bundled inside an AOI. Basically what we have is MSO, MAPC, MAS and MSF instructions, in such way that we control them through input and output parameters.

So far, it is working but sometimes, apparently random, when we deliver a stop command, the axis stops but we can see the .EN bit of the MSO instruction remains Set, no matter its rung condition is already false. When this happens, the Axis won't turn on again and we have to manually Reset '.EN' in the MSO, trigger an MSF and then try again.

We don't understand why the MSO '.EN' bit is still Set regardless of the servo state and its rung condition. This only happens sometimes and when it happens, we have the problem to start again.

When we do not use the AOI bundled Motion Inst, there is not such issue.

Does anyone have a clue?

Thank you in advance.
TWControls
Not a lot to go off of, can you post your program?
b_carlton
Warning - pure guess. Are the conditions which enable the motion instruction the same as those which enable the AOI? For an .EN to turn off there would have to be at least one scan where the enable in to the motion command is false. In other words are you ending the invocation of the AOI as soon as the motion instruction is done?
BobLfoot
QUOTE(b_carlton @ May 6 2009, 09:16 AM) [snapback]81902[/snapback]

Warning - pure guess. Are the conditions which enable the motion instruction the same as those which enable the AOI? For an .EN to turn off there would have to be at least one scan where the enable in to the motion command is false. In other words are you ending the invocation of the AOI as soon as the motion instruction is done?

I strongly think carlton has the answer. Ran into a similiar problem with MSG instructions inside and AOI until I figured out I need to call the AOI for 1 scan after the msg was not enabled.
dcalderonv
Thanks,

I canīt post the program and I know it makes it more complicated.

The AOIs rung conditions are always true, i.e. we don't have rung conditions for the AOIs.

BTW I found this tech note in AB's KB:

http://rockwellautomation.custhelp.com/cgi...p?p_faqid=42520

With that info we could make them work better.

Thanks again.
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