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6ES7 972-0CB20-0XA0

Created by: Jason_Thomas at: 5/22/2014 6:25 PM (14 Replies)

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5/22/2014 6:25 PM	Rate (0)
Jason_Thomas Posts: 5 Rating: (0)	All, I am trying to connect to a CPU 317 via the the back side of the Profibus connector and not having any luck. I have tried using the following PC Adapter Auto 1 PC Adapter Profibus 1 I am not able to disconnect the Profibus line from the CPU. When I connect the adapter to my computer via the USB I am not showing any indication LEDS (Power, USB and MPI) Any help with this would be appreciated.
Jason_Thomas Posts: 5 Rating: (0)
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5/22/2014 8:49 PM	Rate (0)
Ayman Elotaify Platinum Member Joined: 5/28/2008 Last visit: 9/3/2025 Posts: 4522 Rating: (843)	Jason_Thomas All, I am trying to connect to a CPU 317 via the the back side of the Profibus connector and not having any luck. I have tried using the following PC Adapter Auto 1 PC Adapter Profibus 1 I am not able to disconnect the Profibus line from the CPU. When I connect the adapter to my computer via the USB I am not showing any indication LEDS (Power, USB and MPI) Any help with this would be appreciated. Hello, It is normal when connecting adapter to your PC, leds wouldn't lit if the PLC side is disconnected. This PC adapter fed from Automation System, leds will lit when connecting the PLC side (Sub-D 9 pin socket) into the CPU. This PC adapter6ES7972-0CB20-0XA0can work with MPI or Profibus up to 1.5Mbps baud. If you connected the PC adapter to a profibus network with baud rate setting more than 1.5Mbps, you will not be able to communicate with the CPU. I recommend for you to connect the CPU via its MPI interface. Or you can use this adapter "6GK1571-0BA00-0AA0" which can work withMPI or Profibus up to 12 Mbps baud Hope this helps.
	Ayman Elotaify
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5/23/2014 2:46 AM	Rate (0)
kriipc Silver Member Joined: 4/11/2011 Last visit: 7/11/2025 Posts: 132 Rating: (7)	Jason_Thomas All, I am trying to connect to a CPU 317 via the the back side of the Profibus connector and not having any luck. Is this connector connected to the PLC? If you are trying connect on external modules, then this adapter does not work. Adapter needs 24 VDC external voltage (pin 2 0V and pin 7 24VDC). PLC gives it, external modules do not.
	I'm just a human. Mistakes are allowed. Sorry for my english. Only 3 months of training and manuals :)
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5/23/2014 7:40 AM	Rate (0)
Jason_Thomas Posts: 5 Rating: (0)	OK. Thanks. Yes I am trying to connect to the backside of the Profibus connector on the OLM which is down stream of the actual PLC (CPU 317). So will this adapter not work for that6ES7 972-0CB20-0XA0. The Profibus connector on the CPU is not open so Im not able to connect to the CPU with the6ES7 972-0CB20-0XA0at that point. Thanks again.
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5/23/2014 7:57 AM	Rate (0)
Ayman Elotaify Platinum Member Joined: 5/28/2008 Last visit: 9/3/2025 Posts: 4522 Rating: (843)	Jason_Thomas OK. Thanks. Yes I am trying to connect to the backside of the Profibus connector on the OLM which is down stream of the actual PLC (CPU 317). So will this adapter not work for that6ES7 972-0CB20-0XA0. The Profibus connector on the CPU is not open so Im not able to connect to the CPU with the6ES7 972-0CB20-0XA0at that point. Thanks again. Hello, If you could change the bus connector with PG socket you will be able to connect the PC adapter to Profibus DP port of the CPU.
	Ayman Elotaify
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5/23/2014 8:22 AM	Rate (0)
Jason_Thomas Posts: 5 Rating: (0)	Im not able to change out the connector. This is a running system. Im gonna try an check the baud rate an hope for the best.
Jason_Thomas Posts: 5 Rating: (0)
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5/23/2014 8:42 AM	Rate (0)
Navnag Platinum Expert Joined: 11/21/2007 Last visit: 7/25/2025 Posts: 2326 Rating: (309)	Hello Please have a look at this thread : SImatic S7 PC Adapter USB 6ES7 972-0CB20 0XA0 This will solve your problem. You can prepare a special cable to provide external 24VDC to the PC Adaptor for operation at nodes where 24VDC supply is not available on Profibus Connector. Hope this helps Cheers Navnag
	There is no such thing as the last bug in a program There are no stubborn bugs, There are only stubborn Debuggers.
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5/23/2014 8:59 AM	Rate (0)
Ayman Elotaify Platinum Member Joined: 5/28/2008 Last visit: 9/3/2025 Posts: 4522 Rating: (843)	Navnag Hello Please have a look at this thread : SImatic S7 PC Adapter USB 6ES7 972-0CB20 0XA0 This will solve your problem. You can prepare a special cable to provide external 24VDC to the PC Adaptor for operation at nodes where 24VDC supply is not available on Profibus Connector. Hope this helps Cheers Navnag Hello Navnag, That not the case here. Because you can connect PC adapter to DP sockect of any S7-300 CPU. Using external power supply to provide PC adapter by 24VDC is applicable only in case the device you would like to connect doesn't provide 24VDC between pin 7 (+24VDC) & pin 2 (0VDC). In this case only you will need to use external PS. And Siemens have PS dedicated for PC adapter "6ES7972-0CA00-0XA0" But again it's not the case here.
	Ayman Elotaify
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5/23/2014 10:28 AM	Rate (0)
Navnag Platinum Expert Joined: 11/21/2007 Last visit: 7/25/2025 Posts: 2326 Rating: (309)	Ayman Elotaify Hello Navnag, That not the case here. Because you can connect PC adapter to DP sockect of any S7-300 CPU. Using external power supply to provide PC adapter by 24VDC is applicable only in case the device you would like to connect doesn't provide 24VDC between pin 7 (+24VDC) & pin 2 (0VDC). In this case only you will need to use external PS. And Siemens have PS dedicated for PC adapter "6ES7972-0CA00-0XA0" But again it's not the case here. Hello Ayman Elotaify I wrote this post as the user has mentioned that he is trying to connect the PC Adaptor to the Profibus Connector on the OLM ( Not CPU !! ) Jason_Thomas Yes I am trying to connect to the backside of the Profibus connector on the OLM which is down stream of the actual PLC (CPU 317). So will this adapter not work for that6ES7 972-0CB20-0XA0. The Profibus connector on the CPU is not open so Im not able to connect to the CPU with the6ES7 972-0CB20-0XA0at that point. CPU does not have a Connector with PG interface. The connector cannot be changed as system is in operation. Jason_Thomas Im not able to change out the connector. This is a running system. Im gonna try an check the baud rate an hope for the best. I fully agree with you if he is connecting on the CPU Profibus / MPI Port. Cheers Navnag
	There is no such thing as the last bug in a program There are no stubborn bugs, There are only stubborn Debuggers.
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5/23/2014 11:54 AM	Rate (0)
Jason_Thomas Posts: 5 Rating: (0)	Thank you all for the responses. At this point Im guessing I have a BAD adapter. I get a message that says " Unable to connect...faulty or damaged adapter". But I still not getting any indication LEDs on the MPI module. This is the set-up. I have multipe OLM modules. One of which has a place where I can plug into the backside of it. On the connector I have 2 Profibus lines going in. 1 in the receive in going to another OLM module and the transmit side going to the CPU317. I am piggy backing off that connector and trying to gain access to the CPU 317. Normally, I just connect via a ethernet switch....but this system does not have that capablity. So....Im learning as I go. Thanks again
Jason_Thomas Posts: 5 Rating: (0)
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