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Convert puls signal to RPM

Created by: RahulSharma at: 3/13/2012 9:11 AM (8 Replies)

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3/13/2012 9:11 AM	Rate (0)
RahulSharma Posts: 25 Rating: (0)	Dear all, I have digital input from the inductive sensor in PLC to know the feed back for belt drive. I want to convert this signal to RPM, is there any procedure in Simatic S7 400 PLC. Thanks
RahulSharma Posts: 25 Rating: (0)
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3/14/2012 10:36 AM	Rate (0)
Shafi Posts: 3 Rating: (0)	I think you need to provide more details. Are you asking whether you can use the same channel for taking the RPM?
Shafi Posts: 3 Rating: (0)
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3/14/2012 11:34 AM	Rate (0)
umencho Diamond Member Joined: 3/21/2006 Last visit: 3/30/2025 Posts: 10239 Rating: (1183)	Hello, DO you have some special DI or will use ordinary DI? Best regards, Hristo Mihalev

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3/15/2012 8:54 AM	Rate (1)
Jazz_M Gold Member Joined: 9/6/2008 Last visit: 5/7/2022 Posts: 1121 Rating: (86)	Hi What is the MLFB no of your DI card, You will have to calculate for one pulse what will be the RPM for that, say for an example if one pulse come then 3.1 meter of cloth are fed into the system. Based on the pulse we could calculate the meter of cloth fed into the machine. See the Pulse frequency is also a majore factor here. Because if your pulse is less than a second then you will high speed counter. Have fun....
	Jazz
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3/15/2012 5:56 PM	Rate (0)
RahulSharma Posts: 25 Rating: (0)	Dear This is ordinary DI. we are already using it as a pulse. Now what i did i give this pulse to counter and after one minute i reset it and after every second this value transfer to SCADA. But i need some standard way to convert puses to RPM.
RahulSharma Posts: 25 Rating: (0)
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3/15/2012 5:58 PM	Rate (0)
RahulSharma Posts: 25 Rating: (0)	Tagolover Hi What is the MLFB no of your DI card, You will have to calculate for one pulse what will be the RPM for that, say for an example if one pulse come then 3.1 meter of cloth are fed into the system. Based on the pulse we could calculate the meter of cloth fed into the machine. See the Pulse frequency is also a majore factor here. Because if your pulse is less than a second then you will high speed counter. Have fun....
RahulSharma Posts: 25 Rating: (0)
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3/19/2012 4:31 PM	Rate (0)
Jazz_M Gold Member Joined: 9/6/2008 Last visit: 5/7/2022 Posts: 1121 Rating: (86)	Hi Well sorry for the delay , as i said again you need to understannd the pulse frequency, in our case we also used normal DI card. [code] A i 0.0 // DI card Address. L 1 L MW20 // ADDRESS TO STORE YOUR COUNT. + I T MW20 [/code] After that you can calculate the RPM by scaling the total count with the MAX RPM. Have fun...
	Jazz
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4/1/2012 8:09 AM	Rate (0)
TIBI68 Gold Member Joined: 12/1/2009 Last visit: 7/14/2025 Posts: 672 Rating: (147)	Hi, I hope that this is not the real code of your machine while it will count execution cycles only. Independent of the state of the Inputsignal. Regards. It is possible to detect pulses less than a second with using interrupt OB's.
	Last edited by: TIBI68 at: 4/1/2012 9:26 AM Last edited by: TIBI68 at: 4/1/2012 8:19 AM Give us your feedback and show us your respect! We take our free time to support you with our knowledge and experience. If this post is helpfull to you kindly click on "Rate" or "Thank".
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4/9/2012 12:59 PM	Rate (0)
Jazz_M Gold Member Joined: 9/6/2008 Last visit: 5/7/2022 Posts: 1121 Rating: (86)	TIBI68 Hi, I hope that this is not the real code of your machine while it will count execution cycles only. Independent of the state of the Inputsignal. Regards. It is possible to detect pulses less than a second with using interrupt OB's. Hi I think you can, but i have done it by calling it in the Cyclic OB's. Have fun...
	Last edited by: Tagolover at: 4/9/2012 1:01 PM Jazz
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