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how to use timers without individual data blocks?

Created by: ks.senthil at: 7/2/2013 1:40 PM (12 Replies)

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7/2/2013 1:40 PM	Rate (0)
ks.senthil Posts: 6 Rating: (0)	I am using s7 1200 1214 cpu to control 150 motors. i created a FC with TIMERs in it. now if i call the FC 150 times , i need to use 150 DBs in total for Timers. the total work memory is 75 kb, which is not sufficient as i have too much codes . how to use timers without individual data blocks.
ks.senthil Posts: 6 Rating: (0)	Last edited by: O_Moderator at: 7/4/2013 7:51 AM new subject after splitting from /tf/WW/en/Posts/75136#top
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7/2/2013 2:04 PM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 12/28/2022 Posts: 6785 Rating: (1336)	ks.senthil I am using s7 1200 1214 cpu to control 150 motors. i created a FC with TIMERs in it. now if i call the FC 150 times , i need to use 150 DBs in total for Timers. the total work memory is 75 kb, which is not sufficient as i have too much codes . how to use timers without individual data blocks. Hello, 150 Timers is too much even for an S7 300 controller in medium version.(256 for S7 315-2DP) As I Checked you need (150 *1310 byte=196 kbyte) for DB related TON in load memory of CPU.Use a better or change to S7 300 controller.See if you can find similar pattern in function of motors.But note, it is recommended to use one timer for each task to avoid interference. Best regards Hamid Hosseini
	Last edited by: hdhosseini at: 7/2/2013 2:05 PM Demo Channel on Youtube
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7/2/2013 3:34 PM	Rate (0)
ks.senthil Posts: 6 Rating: (0)	Thanks hdhosseini, along with 150 motors i also need RS 485 communication board . Is it available in s7 300.
ks.senthil Posts: 6 Rating: (0)
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7/2/2013 4:26 PM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 12/28/2022 Posts: 6785 Rating: (1336)	ks.senthil Thanks hdhosseini, along with 150 motors i also need RS 485 communication board . Is it available in s7 300. Hello, RS 485 as physical layer for PROFIBUS and MODBUS is available.For MODBUS there are different versions.For both options, there are cases integral on CPU or possible to add via communication processors later as required. what is your required protocol? Best regards Hamid Hosseini
	Demo Channel on Youtube
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7/2/2013 5:57 PM	Rate (0)
DS SURESH KUMAR Bronze Member Joined: 4/17/2012 Last visit: 8/13/2022 Posts: 474 Rating: (10)	ks.senthil I am using s7 1200 1214 cpu to control 150 motors. i created a FC with TIMERs in it. now if i call the FC 150 times , i need to use 150 DBs in total for Timers. the total work memory is 75 kb, which is not sufficient as i have too much codes . how to use timers without individual data blocks. Hi, Instead of using 150 DB . you can create your own on delay timer by using the system clock pulse and compare instruction. this won't affect your memory, as well as it don't increase the load. You can get the one second pulse from Mx.y bit. and connect this to add instruction . take the add output value as comparator input 1 and use the other comparator input for set time . then comparator start to check the Setpoint time and input once it reach the Setpoint output will become high. use one reset bit to made the add value become zero. ----\| \|----(p)--------[use add instruction]--------\| ==I \|------------( ) ------\| reset bit \|------------[ move value 0 to add instruction input] you can creat this logic in fb as a multiple instance and use it for these 150 motors. and more

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7/2/2013 6:25 PM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 12/28/2022 Posts: 6785 Rating: (1336)	Hello, personally I don't recommend using a personally developed TON to be used instead of standard functions.You can check it here in STL for S7 300/400.You can develop a same idea.Memory required for DB to keep data of my function FB1 is around "140 bytes".It is atrade off between reliability and cost reduction. Best regards Hamid Hosseini Attachment DB_FOR_FB1.jpg (560 Downloads)
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7/12/2013 11:09 AM	Rate (0)
ks.senthil Posts: 6 Rating: (0)	Thanks DS Suresh Kumar, i used your logic and it works fine. I am using FC with temp variables, which contains integer values. when i use this FC in more than 1 place, the temp integer values has random values. how to initialise or have control over these temp integer values. it will be for more helpful if you provide example program for FC with temp variables.
ks.senthil Posts: 6 Rating: (0)
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7/12/2013 8:34 PM	Rate (1)
0_Einstein Diamond Expert Joined: 7/7/2010 Last visit: 2/6/2023 Posts: 13082 Rating: (2124)	ks.senthil Thanks DS Suresh Kumar, i used your logic and it works fine. I am using FC with temp variables, which contains integer values. when i use this FC in more than 1 place, the temp integer values has random values. how to initialise or have control over these temp integer values. it will be for more helpful if you provide example program for FC with temp variables. At the beginning of each FC with a temp variable, you absolutely MUST give is a value before using it later in the programming. At the end of the FC, the next FC will get some random value, not necessarily the value it was when your FC stopped running. It really sounds like you need to use an FB and have static variables that will keep their values from one call of the function to the next. Either that or use a global DB for those 'temp' values that are not really temporary....
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7/18/2013 8:13 AM	Rate (0)
O_Moderator Diamond Member Joined: 4/24/2009 Last visit: 2/6/2023 Posts: 2685 Rating: (135)	Follow-up question splitted to is it possible to find which input i received first in the CPU? Best regards O_Moderator
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7/18/2013 12:57 PM	Rate (2)
William_B Posts: 5225 Rating: (1160)	ks.senthil I am using s7 1200 1214 cpu to control 150 motors. i created a FC with TIMERs in it. now if i call the FC 150 times , i need to use 150 DBs in total for Timers. the total work memory is 75 kb, which is not sufficient as i have too much codes . how to use timers without individual data blocks. Gentleman, Forgive my entry to this thread, I am by no means an expert as you are. According to me it does not take as much memory to create 150 IEC timers. I must not be understanding the numbers right.. Attached see a global DB with array of 150 timers and the memory consumption thereof. For the CPU1214C there are 4MB load memory available. Please tell me what I am missing. Then to further the discussion.. a) I can imagine the 150 timers is used for ssequence starting. It is possible to use shift register method and x1 timer for this. If the time values differ, you can create a look-up table to load new values in, combined with a indexer. b) If the logic is more complicated it is still not needed to create 150 FC's. Create x1 master FB that calls the x150 instances. There is one multi instance capable FB. The memory of the multi instance FB comes from the single master FB. If I am understanding the issue wrong.. please do help me right. Greetings. w Attachment memory usage for creating 150 iec-timers.jpg (696 Downloads)
William_B Posts: 5225 Rating: (1160)	Last edited by: William B. at: 7/18/2013 1:10 PM [shame] sorry - missing about attachment
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