need help with PLC 2 to PLC 5 conversion!

[LuCyLut]

Hi everyone,

I'm currently a college student doing my summer intern. As part of my senior project I need to convert a PLC 2 system into a PLC5. I have very lil PLC knowledge since we don't really learn this stuffs at school. Engineers at work are too busy to help me out so I have to research and learn everything on my own. Can someone please help me as to where should I start? What things I should watch out for when switching the processor? I would appreciate it. Thank you!

 

[rgurin]

As a starting point, you may want to take a look at this technote from the Rockwell Automation Knowledgebase.

I realize that a good portion of this technote is promoting a Rockwell conversion service (which you have been asked to provide ) , but the section titled "PLC-2 Conversions" includes some useful information (which instructions don't convert, which instructions need to be modified, data table formats, etc.)

Also, it would be helpful to let us know what hardware/software you have been provided with.

Finally, this link from the Rockwell Automation Literature Library provides a PDF user manual for DOS-based PLC-2 to PLC-5 conversion software. Even though the manual is old, it may also contain information that will help in the actual conversion process.

Good luck! I'm sure others on the site will have additional information that will get you on your way.

 

[Doug-P]

The list is long but here are some things to check:

The PLC-2 doesn't do DH+ and the PLC-5 doesn't do DH. If data highway is involved you'll need to address this.

The PLC-5 also doesn't do local I/O. If there are remote racks remote I/O adapters will be needed (1771-ASB).

The PLC-2 can power some of its I/O racks with a built in power supply - the 5 can't. You may need additional power supplies.

 

[Gerry]

1 out of 3 ain't good

The list is long but here are some things to check:

The PLC-2 doesn't do DH+ and the PLC-5 doesn't do DH. If data highway is involved you'll need to address this.

The PLC-5 also doesn't do local I/O. If there are remote racks remote I/O adapters will be needed (1771-ASB).

The PLC-2 can power some of its I/O racks with a built in power supply - the 5 can't. You may need additional power supplies.

1785-KA to connect PLC5 to DH (it's not great though)
1770-KA3 to connect PLC2 to DH+

The "L" processors (e.g. 5/40L) support local and remote I/O.
The adapters are 1771-ALX (local) and 1771-ASB (remote).

You're right about the rack power - if it's a 2/20 or 2/30.

 

[rsdoran]

Please define what you mean by "local I/O/"

 

[LuCyLut]

thank you!

Thank you for everyone's help. I really appreciate it! I'm so glad I found out about this website. It's even better than the trainning class I got! I guess I need to give more details as to what I have. I have the program with a PLC 2/05 processor. I need to convert it to a PLC 5/40. I have most of the programs converted but as far as the hardware and what I need to watch out before switching the processor. Does anyone know a good link that would give me some basic knowledge of PLC for newbies like me? I'm picking up bits and pieces from the engineers at work but there are alot of basic stuffs that I don't really know. Please help! I need to do this to graduate! and learning PLC is very fun!

 

[bwheat]

Check the chasis series or revision. Some older chasis will not work with the PLC 5 processor because the power supply connector and cable interferes with seating the card. If you dont want to change the rack and have room you can add chassis mount power supply. This should be on Rockwell Knowledgebase somewhere.

 

[Doug-P]

1 out of 3 ain't good

You're right. In future I shall refrain from such outbursts.

 

[Gerry]

Please define what you mean by "local I/O/"

In the context of this thread, local I/O is either in the same chassis as the processor or connected directly to the processor. Data is transferred in parallel fashion, all in one hit, synchronous with the program scan. The cables are fat multicore's with huge connectors. Operating distance (cable length) is limited - hence the term "local".

It is particularly useful in applications with large numbers of block transfer modules spread through various chassis, due to the high-speed synchronous data transfer. All BTX modules in all local chassis are updated every I/O scan. By contrast, remote I/O will only update one BTX module per chassis, per remote scan.

 

[rsdoran]

The list is long but here are some things to check:

The PLC-2 doesn't do DH+ and the PLC-5 doesn't do DH. If data highway is involved you'll need to address this.

The PLC-5 also doesn't do local I/O. If there are remote racks remote I/O adapters will be needed (1771-ASB).

The PLC-2 can power some of its I/O racks with a built in power supply - the 5 can't. You may need additional power supplies.

Gerry, I should have phrased the question with more detail. Doug stated the PLC-5 does not do local I/O and I did not understand that statement.

 

[bwheat]

Local I/O as far as the 2's and 5's go are I/O that resides in the same chasis with the processor. The PLC-5/XXL Processors support "Extended Local" I/O, which is what Gerry described.

 

[mellis]

Check out this Knowledge Base article. It covers the hardware gotchas for converting PLC2 to PLC-5.


A16647: PLC-2 To PLC-5 Conversions

 

[Gerry]

Local I/O as far as the 2's and 5's go are I/O that resides in the same chasis with the processor.

True for the mini 2's but not a 2/20 or 2/30.