[Chris Elston]

Below is the result of your feedback form. It was submitted by
DLEvans (logicsense@msn.com) on Saturday, March 12, 2005 at 03:55:51
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question: Usage


comments: I would be very grateful if you would do a tutorial on Block Transfers, read and writes. Explain how to identify the channel being used to collect data from an analog card in a PLC and SLC, control words, and scaling for the purpose of trouble shooting. I have spent many hours on my laptop trying to find something to help me understand the workings of a BTW and BTR. Thanks
Dennis

[Chris Elston]

Ron Beaufort is once again the "MAN" in this posting.

[Contr_Conn]

I can't compete with RON - no one can explain better. Just want to answer this question:

Quote

Explain how to identify the channel being used to collect data from an analog card in a PLC and SLC, control words, and scaling for the purpose of trouble shooting

Each block transfer in your program has a RACK number.
This is a logical rack address assigned to your remote I/O adapter or local rack.

Look at the Channel Configuration of your processor.
It can have up to 4 RIO channels.
Each channel has a table of racks connected to this channel.

Find your rack number and this will be a channel it connected to.
If you can't find it, and number is between 0 and 3 - this may be module in the local rack.

In your ladder you should not worry about channel:
processor does it for you based on channel configuration table.
You specify RACK, GROUP, MODULE only.

Get 1785-6.5.12 User manual - it describes addressing scheme

This post has been edited by PLC_Cables: 12 March 2005 - 09:52 AM

[Ron Beaufort]

Greetings to all,

and thank you for the kind compliments ...

a note to Dennis (the original poster?) ... if you can post some specific examples of the rungs that are giving you problems, then I’d be happy to help nail down the ideas for you ... it would also be extremely helpful to have a list of your I/O hardware (chassis, modules, etc.) handy ... the more details you include with your question, then the more detail we can provide in our answers ...

and keep in mind that there are some differences in the way Block Transfers are used in the PLC-5 and in the SLC-500 platforms ... so if both are giving you trouble, it would be a good idea to include examples of both ...

best regards,
Ron