Help - Modicon 984

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Thread Starter

floorpan

i need to get the status of a block of discrete bits ie 01600 to 01615 in a modicon 984 and cant find any info in the limited manuals i have. if i can address them directly it would be nice but if i have program in a move to a register then so be it. i dont have a plc to play with only the one operating at the clients site hence the question here.
first job with a modicon. AB/Omron/Uticor all make it easy so i hope it is available in a modicon.
 
You could utilize the SENS instruction. The top node of the instruction indicates bit location. The middle node would be the starting 0XX reference. The bottom node in this case would be a 1 for 16 contigious coils.
 
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Bruce Durdle

It depends on the command.
In general, you can treat a block of 16 bits (starting at n x 16 +1) of input or output exactly as you can a register. The SENS function will check the status of an individual bit in a group of registers or I/O locations. The bit number goes into the top of the function block; the initial register or bit address in the middle, and the bottom holds the total number of registers or 16 bit I/O words to be checked.

You can download the full 984 programming instructins from the Modicon website "www.modicon.com":http://www.modicon.com

Bruce.
 
J
What model processor do you have? 984 is not a suffcient description.

Go to "http://www.schneiderautomation.com":http://www.schneiderautomation.com and download a copy of Modicon Ladder Logic Block Library User Guide #840USE10100. This is a listing of all available Modicon 984 commands, although not every processor can use every one.

To sense bits, the SENS command is available in all processors but the NOBT command is only available in the Quantum series.

To set bits, MBIT can be used everywhere, but the Quantum family also has SBIT.
 
B

Bradley G. Hite

Hello,

> i need to get the status of a block of discrete bits ie 01600
> to 01615 in
> a modicon 984 and cant find any info in the limited manuals i
> have.

Most HMI can access the 0xxxx addresses directly. What system are you using to access the 0xxxx addresses? Search on Modicon's web site for the 984 Ladder logic manual. "http://www.modicon.com":http://www.modicon.com

> if i
> can address them directly it would be nice but if i have program in a
> move to a register then so be it.

The BLKM (Block Move) instruction can perform that function for you.

Let me know if you have additional questions.

Bradley G. Hite
Intertech Inc.
mailto:[email protected]
http://www.myplc.com
Teaching Practical Skills for a Technological World
 
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