S7 PLC

[lesliemcg]

Hi all, new to profibus
i have a S7-300 (313C-2DP) and will have profibus in the system
6 drives and 10 pneumatic valves will be controlled on this bus
one cylinder valve is very fast acting (12ms). will the profibus be able to switch on/off at this rate or will i have to hard wire to this valve from an output in the PLC
i know the data rate is up to 12MB but has anyone had a fast acting device tried and tested (and worked before)

thanks in advance
lesliemcg

 

[jacekd]

Hi,
If you really need this speed I'd suggest useing interrupts.

BTW, are you sure that 12ms after energizing the valve something is done and you have to switch it off ?


Regards,

Jacek

Do it right or don't do it at all.

 

[lesliemcg]

yes jacek, it really is a fast cylinder and high speed valve
the cylinder slices through a hose and gets out of the way for the next one
works well though
leslie

 

[jacekd]

OK,
Then if Profibus is a must you can go for isochrone mode with your CPU. Be careful with your network config - only some ET200M and ET200S interfaces and modules support this mode. Also you shouldn't use many slaves and preferably switch off all diagnostic ints and time of day sync.
However it won't be possible to achieve time granulity better then 1-2 ms.
If this is not enough try interrupts.
If still no luck then think of FM352-5.

Regards,

Jacek

Do it right or don't do it at all.

 

[masterthailand]

Dear. whome may be concern.
this massages from thailand. now I have a printing machine that the machine is control by PLC which brand name SHARP . I would like to ask you when you are know more description of this model. please tell me later.
thank
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