Using 1771-SDN for plc500

[Audy86]

Hi,

I have to use a 1771-SDN devicenet card for a remote control panel which is controlled by PLC5000. Now, it looks like 1771-SDN is used for communicating with PLC-5 not PLC5000 widely..I am desperately in need of help how to make it work!!

Thanks in advance!

 

[Mike_RH]

Explain more clearly what you want to do?
Specifically which CPU, what is the "remote panel".
More information might result in an answer / suggestion.

 

[Audy86]

I have to set up a communication between a 1771-SDN devicenet and plc5000 through a remote I/O protocol. The Panel in which i am going to have my 1771-SDN device-net is communicating with plc5000 through remote I/O (using 1771-ASB).

Please see the attachment, the remote panel is C594 witch is using rack 2 & 3 and communicating with PLC_411.

Thank you.

 

[Mike_RH]

You should be able to use MSG instructions in the ControlLogix to perform block transfer reads and writes to the 1771-SDN module. You will also need RSNetworx software to configure the scan list for the SDN.

 

[Ken Roach]

The contents of the Block Transfers should be identical to how they would be in a PLC-5. It's just the MSG instruction configuration that looks different than the BTR and BTW instructions from the PLC-5 operating system.

I'm gritting my teeth looking at the layout because it suggests you've got a lot of devices hooked up to this RIO network. The 1756-DHRIO is notoriously skimpy on block transfer capacity, so if you have a lot of other analog modules this is could get tricky.

This is definitely not the preferred way to connect a ControlLogix to DeviceNet, but I suppose there are reasons.

Is there an existing DeviceNet network, and do you have the 1771-SDN Scanlist and a RSNetworx for DeviceNet project file ?

 

[Audy86]

First of all, Thanks to Mike and Ken.

I am connecting four (4) armorstarts with the 1771-SDN for running conveyor 594 (C594) as you can see in the layout. Now this 594 panel slots are plc5(hardware) and controlled by plc5000 (software) and thats the reason I have to use 1771-SDN.

I do not have any existing devicenet network or scanlist but im hoping to configure a scanlist using RSNetworx.
Is it too much to ask if you have any kind of example for MSG instruction configuration to perform Block Transfer? I would really appreciate.
Thank you.

 

[JeffKiper]

I don't know why but I have it in my mind that the 1771-SDN had to be the Master on DeviceNet network.

 

[Ken Roach]

The 1771-SDN will be the Master on the DeviceNet, with the ArmorStarts as slave devices on the DeviceNet.

It's just unusual that it's been placed in a remote 1771 chassis on a RIO network with a ControlLogix and 1756-DHRIO as the scanners. That's a blend of 1978 and 1996 technologies.

The 1756-DHRIO user manual covers the basics of configuring the RIO network, and there are some simple Block Transfer logic examples for the 1756-DHRIO in the RA Knowledgebase.

Which versions of RSLogix 5000 and RSNetworx are you using ? If I happen to have the same versions installed I can post a simple example.

 

[JeffKiper]

Can you say multi-hop of signals?

 

[Ken Roach]

In 1996 my DeviceNet seminars were titled "Nothing but Net". Thanks, Michael Jordan, for the easy marketing slogan.

 

[Audy86]

Thanks a lot! my RSLogix5000 version is 16 anr RSNetworx version is 11. Your image gives me an idea how i need to do it. I am am planning to do the following but instead of using plc5 i will be using plc5000, also how do I configure the control block using MSG instruction?

Thanks you once again!

 

[Ken Roach]

That's exactly what my screenshot shows, with two separate MESSAGE type control tags.

You'll have to configure the Path block yourself... that just involves selecting the SDN module object from the I/O tree.

 

[Audy86]

Thank you so much..makes sense !

 

[Ken Roach]

In my example I showed a Block Transfer length of 64. That's incorrect because I mis-remembered.

When an A-B device that uses the old PLC-5 backplane or the RIO network wants to use multiple Block Transfer data blocks, the only way it can tell them apart is using the Size.

You didn't encounter this with ordinary analog modules because they just had an Input and an Output BT.

But when you get into complex devices like the 1771-SDN or a PanelView, they often need to use multiple Block Transfers.

Look in the 1771-SDN User Manual, on page E-4 and E-6. It shows you that the 62-word Block Transfer is the one that's cardinally important because it includes the Command Word as well as a large block of I/O data.

Back when I worked with 1771-SDNs, I would always have Appendix E from the User Manual printed out and sitting on my desk to sort out the data mapping and control and status words.

 

[Audy86]

This is what I am doing right now..I am using a datalink (INT[62]).
I am confused if the BTW/BTR of 62 words will contain necessary command or i have to configure it individually? I am looking at the chart you have sent me.

Thank you for taking time and helping me out with this!