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The Best solution is?

Created by: pago06 at: 3/27/2006 4:24 PM (8 Replies)

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3/27/2006 4:24 PM	Rate (0)
pago06 Posts: 36 Rating: (1)	Hi all! I've a doubt and that's why i'm here! My prob is: I've got to implement a software to control the blowers from a thermoelectrical station. The process (or Cycle) is to blow all the 10 blowers or the ones that are selected. In case all the blowers selected it is easy to do (by now). But in case to have the blowers 1 and 5 selected (that's an example), how should i do? I was thinking using a sequencer, but i guess it would be more complicated. Would the Shift bits Right (or left) work? Hope this info helps you to help me! if needed more info just tell. i can explain all the process, i didn't do cause i would be too much to read! P.S. - I'm using Simatic S7 on a 314 CPU.
pago06 Posts: 36 Rating: (1)
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3/28/2006 9:17 AM	Rate (0)
Cicero Gold Member Joined: 10/10/2005 Last visit: 10/18/2024 Posts: 1921 Rating: (136)	Hello, regarding to your inquiry we would like to inform you. I´m not sure what is exactly your problem but I hope I can help you with some examples which do you will find in the internet. In refer to your description you want to control example blower 2 and 3, or blower 1 and 5, or blower 2, 4 and 6. In STEP 7 there is a function of jump distributors. Here you can with the programming of the jump distributor to control the special blower in each jump. Please see the home page of the SIMATIC customer support: http://www.siemens.com/automation/csi_en/product By the home page you will find the FAQ with informations of the jump distributor: "How do you implement jump distributors in STEP 7?" by the Beitrags-ID: 20713380. Expample: L jump number //Load the jump number JL End; //Jump to jump label End //if the number of jumps is greater than //the number of SPA statements JU M00; //Jump to jump label M00 (Accu = 0), //here control blower 2 and 3 with an AND-instruction JU M01; //Jump to jump label M01 (Accu = 1) ////here control blower1 and 5 with an AND-instruction JU M02; //Jump to jump label M01 (Accu = 2) ////here control blower2, 4and6 with an AND-instruction End: ... An further example with the programming of jump distributor there is a faq "Calculating the week day with a jump distributor" which do you will find by Beitrags-ID: 12535573. We hope that these examples are successful for you so that you can generate some ideas to programming the control of blowers. With best regards Cicero

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3/28/2006 9:35 AM	Rate (0)
Liftaren Posts: 21 Rating: (2)	Are the blowers to run in sequence? Blower 1, then blower 2, then blower 3 and so on until all selected blowers and through? Then it would be easy to use two words and a counter and the shift right instruction. One word that keeps track ofwhat blowers are selected, one word that keeps track of wich blower to "blow" and a counter to make sure only one blower is started. Both these words are shifted one step to the right on a rising edge of "something" and the counter is counted up at the same time.
Liftaren Posts: 21 Rating: (2)	Last edited by: Liftaren at: 3/28/2006 9:36 AM
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3/28/2006 11:58 AM	Rate (0)
pago06 Posts: 36 Rating: (1)	[quote user="Liftaren"]Are the blowers to run in sequence? Blower 1, then blower 2, then blower 3 and so on until all selected blowers and through? Then it would be easy to use two words and a counter and the shift right instruction. One word that keeps track ofwhat blowers are selected, one word that keeps track of wich blower to "blow" and a counter to make sure only one blower is started. Both these words are shifted one step to the right on a rising edge of "something" and the counter is counted up at the same time. Yes, the blowers are to run in sequence but only by the selected blowers. I was thinking something like you said as a solution. To be more explicit i'll give here an example of the process. Example: The are 10 blowers in total. Before start sequence the operator selects wich blowers to include onSeq. (switch On/Off), then push the Start button. In this case lets pretend operator selected Blowers 1, 3,4-8,10. Pushing the start button the sequence should be: Verify Input correspondent to Blower 1 and if included (='1'), execute the blow process for that blower. Verify the input correspondent to blower 2 and if not included (='0') then it should jump to test the next input. And so on... This should be the process. I guess i can solve the problem with something like the solution you provided! I was thinking about using the Compare instruction in union with the shift one track word right! But i'm open to further solutions Thanks!
pago06 Posts: 36 Rating: (1)	Last edited by: pago06 at: 3/28/2006 12:27 PM
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3/29/2006 3:54 PM	Rate (0)
pago06 Posts: 36 Rating: (1)	Guys! [:blush:] I've been trying to implement the Liftaren solution but i couldn't implement the sequence [:(] Somebody to help me![:blush:] Thanks in advance!
pago06 Posts: 36 Rating: (1)
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3/30/2006 8:08 AM	Rate (0)
Liftaren Posts: 21 Rating: (2)	I attach a little sample code [:)] Function of the sample: M10.0 starts the sequencer and the sequence keeps on running until M10.0 is reset again. MW12 is the word for the start orders, for 10 blowers set this to w#16#07FE. The bit in the position to the right end (M13.0) must start as being "0". MW16 is for the selection of blowers. In the sample code it is set to w#16#0122 to start blower 1, 5 and 8. MW14is to keep track of where in the sequence we really are, since it is only bit M13.0 and M17.0 that are compared for the start order (due to the shifting instruction). M0.2 is the systempulse 100ms which shifts the word to the right and count up the counter. Replace this with whatever you want to trig the shifting. Looking at the code now, I see that there is really no need for two words to use in the shifting since MW12's bits are all set to "1" for all the blowers. But sometimes the mind works slower than the fingers...[:)] Attachment FC10.zip (903 Downloads)
Liftaren Posts: 21 Rating: (2)
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3/30/2006 1:06 PM	Rate (0)
pago06 Posts: 36 Rating: (1)	Thaks a lot! I'll try it and try to adapt to new configurations. I guess I'll need to add more blowers to word (MW12) cause some blowers have to blow 2 times if included in the sequence (one at start and another at the end). Each of these would probably have to blow in three phases. (Side 1, Side 2 the Side 1). Thnx! once again!
pago06 Posts: 36 Rating: (1)
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3/30/2006 1:13 PM	Rate (2)
Liftaren Posts: 21 Rating: (2)	If you need more blowers, you can use an MD instead of MW. Then you'll get 31 objects instead of 15 [:)] (one object is lost since the right-most bit must be 0 at start).
Liftaren Posts: 21 Rating: (2)
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3/31/2006 5:30 PM	Rate (1)
pago06 Posts: 36 Rating: (1)	Well! Thanks a lotLiftaren by your help. It was a big step ( 7 [:P] )you help me to give! I'm creating a "template" sequencer using MDs and some other paramenters. Thnx!
pago06 Posts: 36 Rating: (1)
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