Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

MPI Connection between CPU313C and 3 OP73 Operating Panels

Created by: Suhas at: 11/22/2009 8:16 AM (5 Replies)

Rating (0)

Thanks 0

6 Entries

11/22/2009 8:16 AM	Rate (0)
Suhas Posts: 27 Rating: (0)	Dear All, Iam using CPU 313C and 3 Op73 Operating Panels. I want to connect cpu and op's through MPI Cable. I have got 4 Connectors which are having provision for In and Out Connections. i have connected Connector near by CPU Out connection terminals (A2,B2) to first OP (A1,B1) and first OP(A2,B2) to next OP(A1,B1) and second OP(A2,B2) to Third OP(A1,B1). I have swithced on the resistors DIP Switches of CPU Connector and last OP connector ON. I have given MPI address for Op's as 3,4,6 and CPU Address as 2. But iam not able to communicate with CPU from the OP Panels. Can anybody help me out to enable the communication. Waiting for your valuable suggestions. Thanks & Regards, Ravindra.
Suhas Posts: 27 Rating: (0)
Suggestion To thank Quote Answer

11/22/2009 9:46 AM	Rate (0)
Ayman Elotaify Platinum Member Joined: 5/28/2008 Last visit: 1/2/2025 Posts: 4518 Rating: (841)	Hello Suhas, It looks like that you have connected the sockets correctlly. Check that you didn't duplicated the MPI address. Each OP should have unique address as per the application software. Please have a look on the attached screen shot. Also check that the termination resistor of the first and second OPs are set to OFF status. Also please tell us what's the lengthes between each OP and the other and also the CPU. Regards, Attachment OP73.JPG (168 Downloads)
	Ayman Elotaify
Suggestion To thank Quote Answer

11/22/2009 10:53 AM	Rate (0)
IBN-Service Posts: 8946 Rating: (999)	Suhas i have connected Connector near by CPU Out connection terminals (A2,B2) to first OP (A1,B1)... That is wrong. If you connect only one cable to the plug, you must always use A1,B1! Only using A2,B2 is not allowed!
IBN-Service Posts: 8946 Rating: (999)
Suggestion To thank Quote Answer

11/22/2009 11:58 AM	Rate (0)
Suhas Posts: 27 Rating: (0)	Hi, U mean to say i have to connect A1,B1 terminals for connector near by CPU. Length of the cable is within 1 mtr only.All CPU and OP's are located in the same control panel. Waiting for your suggestions. Best Regards, Ravindra
Suhas Posts: 27 Rating: (0)
Suggestion To thank Quote Answer

11/23/2009 12:23 AM	Rate (0)
fritz Diamond Expert Joined: 10/7/2005 Last visit: 1/17/2025 Posts: 3030 Rating: (1058)	Suhas U mean to say i have to connect A1,B1 terminals for connector near by CPU. Hello Suhas that is exactly what IBN-Service said and he is correct! Any Profibus (or MPI) Plug that has only ONE cable in it needs to be connected to A1/B1 terminals and the terminating resitor switched ON (which also disconnects theinternal loop to A2/B2 and the reason why your intial connection does not work). I would also recommend to haveAT LEAST 1 meter cable lenght between two Plugs, especially at baudrates of 1.5Mbps or higher to avoid any potential for upsetting the bus (every Plug/connection causes an impedance mismatch and havingless than a meter of cable between two Plugs compounds this effect). I hope this helps
	Last edited by: fritz at: 11/23/2009 12:34 AM fixed typos Cheers fritz The advice and opinion given in this thread is that of the author and does not necessarily reflect the views of I S Systems Pty Limited. To find out how I S Systems can help you with your automation needs please visit www.issystems.com.au.
Suggestion To thank Quote Answer

11/23/2009 3:49 AM	Rate (0)
how come Posts: 382 Rating: (47)	Hi Suhas, Apart from the rest valuable inputs, connect your profibus with the connectorthis way CPU [A1B1, Resistor ON] to 1stOP73 [A1B1, Resistor OFF] from [A2B2 of 1stOP73] to 2ndOP73[A1B1, Resistor OFF] from [A2B2 of 2ndOP73] to lastOP73[A1B1, Resistor ON] Always remember the 1st and the last node of the profibus connection of the switch is "ON" and the rest in between are in "OFF" position and start with A1B1 as IBN_Service mention. In addition, alsotake note of the profibus shielding and proper termination to the connector.I have attached a sample for your reference. Hope this helps. with regards, how come Attachment Profibus Connector 90deg Double 9pin Screw Type.pdf (138 Downloads)
how come Posts: 382 Rating: (47)	Last edited by: how come at: 11/23/2009 4:04 AM Last edited by: how come at: 11/23/2009 3:53 AM
Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on