novaqui1

Control of random amount of machines

6 posts in this topic

 

Hi All.

I hope you are all doing excellent and also, hope you can help me.

Today I contact you as I am having some issue when programming a PLC.

I need to create a piece of software that:

1) Can control a random number of machines at any given time.
2) Each machine is a slave 
3) They are exactly the same, do exactly the same thing.

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So far I have managed to create a piece of code that allows me to control a fixed number of machines but things get complicated when one job does not need 10 machines but 20 and the next one needs 15, and the next need 5 and so on.

I have thought to use arrays to do this job but this is an area I have not touched at all and I would like to ask for your advice in this area.

I hope everything is understood.

Thank you very much for your help in advance.

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Software and plc being used? Also you say random but I presume that if a machine needs to be used then it must be selected on an HMI of some sorts? The software and plc you use first needs to be know before real advice can be given

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Just now, cHud said:

Software and plc being used? Also you say random but I presume that if a machine needs to be used then it must be selected on an HMI of some sorts? The software and plc you use first needs to be know before real advice can be given

Thank you for your answer.

I am new here, I thought the tags were more than enough, sorry for that. 

The software: Unity Pro.

 Master PLC: M340.

Slave: M221

BUS: Modbus TCP/IP.

 

We do have an HMI, the thing is that if the amount of machines needed changes per job.

So if one job tomorrow needs 10, instead of 400 that are stored in the master PLC (M340) then the master must be smart enough to recognize how many machines are being used on that day and give the commands required to the slaves.

Thanks

 

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Sorry didnt see the tags. So each machine has a m221 controlling it and the m340 telling each m221 when to operate? 

I would go the Function block route for each machine. If all are identical then you only have to create one function block then paste this function block for the amount of machines you have. Then each function block can have an enable/disable leg on it. Sorry cant give more advice as as the scope of what the setup there is is a bit vague

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On 30/08/2016 at 5:00 PM, cHud said:

Sorry didnt see the tags. So each machine has a m221 controlling it and the m340 telling each m221 when to operate? 

I would go the Function block route for each machine. If all are identical then you only have to create one function block then paste this function block for the amount of machines you have. Then each function block can have an enable/disable leg on it. Sorry cant give more advice as as the scope of what the setup there is is a bit vague

Sorry for the vagueness it is just there is some info I can give.

 

However, I have applied that method you mentioned, created a function block per machine/station, which is great and everything work beautifully however, everything starts to get complicated when you want to apply things like E-Stops that work with an ever changing amount of units.

 

Does it make sense?

 

Thanks.

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Are these estops and machines in one area? If so it shouldnt matter how many machines are in operation. If any estop is pressed hard-wiring through safety relays should disconnect power to starters vsds etc on all the machines.Even if a machine isnt working and it has estops around it the estops should be healthy for other machines to operate. Well thats just my opinion.

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