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Quick question that I have been banging head on wall from.

For some odd reason, I cannot toggle bits in the RUN or REMOTE RUN mode, and only can toggle outputs while in programming mode. None of the forces seem to have any effect at all on either mode. As I check the config tables I cannot change states at all. This is starting to get very frustrating.
Im wondering if it may be in the settings or something to do with scan time.
Please help
Cheers

You will need to be in REM RUN.

Is the logix icon at the top of your screen spinning while you are trying to do this?

Also if you are toggling a bit but the logic is telling it to go back to its former state....the logic wins.

It could be that the bits you are trying to toggle are being changed back elsewhere in the program. If I need to go around a certain bit to get an output to turn on I'll usually use a branch with a test bit that I can toggle as needed. Just be sure to remove the branch and test bits when you are done.

*And BCS wins this round of the typing race!

Bubba.

willxfmr said:

*And BCS wins this round of the typing race!

Bubba.

Click to expand...

If your not "good" you at least have to be "fast" :site:

Kevin,

You disappeared so I guess you got it.

If not one last thing that might be happening.

If you are going from RUN to PROGRAM and then back to REM RUN......the plc is not running.

Switch the PLC to RUN, then to REM RUN and give it a try.

The logix icon will be spinning when you are online with a functioning PLC.

BCS

Still Have not figured it out. I am in Remote Run as you had stated. I think that you are right in the sense that there is something wrong with the program. I am not trying a very difficult program. it is simply a seal in rung. Just cannot seem to figure out why I am unable to toggle bits. The logo is spinning and I know my PLC is receiving the signal from the indicator light. Any more suggestions as to what the cause is?
Thanks

What PLC are you using? Can you share the program? (zip it first, go advanced and add as attachment).

It may also help if you tell the forum the bit address you are trying toggle. Along with the program.

Hi Kevin.

Initially you refer to both toggling bits and forcing them. which is it? or are you attempting to do both?
the forces will not activate unless you enable forces for the CPU.

Cheers
Guy

My thought is
If you are trying to toggle an input from the " I " table the input will always win
due to its position in the scanning of the process

I'm betting on guydegraeff's line of reasoning ...

Initially you refer to both toggling bits and forcing them. which is it?

Click to expand...

he's absolutely correct: a TOGGLE and a FORCE are NOT the same thing - although many people believe that they are ...

and the following statement is troubling:

I know my PLC is receiving the signal from the indicator light

Click to expand...

an indicator light is an OUTput ... PLCs do not RECEIVE signals FROM lights - instead they send signals TO lights ... or did you mean to say something like the following instead? ...

I know that my PLC is receiving the signal that I am sending it - because the indicator light changes state ...

Click to expand...

I'm not trying to be picky - but remember that we can't see what you see ... we only know what you TELL us - so details make a big difference in how much detailed help we can give you ...

also ... do you have actual real-world outputs (lights, etc.) hooked up to your system - or are you just looking at the "green on the screen" indications on your computer? ... in that case, you need to know that in Allen-Bradley systems, FORCES do not affect the ONE/ZERO status of OUTput bit/boxes - so the "green on the screen" indications will not change state (if that's what you're trying to do) ...

TIP: show us a screen shot of what you're seeing - and give us some more detail ... I'm sure that we can help - but right now we're just guessing at what you're dealing with ...

and welcome to the forum ...

And another WAG.....

Did you make a new LAD for this "simple program"?

If you did, the PLC may not be implementing that LAD if you did not add a JSR to call it.

BCS

T4:0 I:1/0 I:1/1 O:4/0
--------[/]--------+-----[ ]------+-----[/]-----------------------------( ) ------|
DN | |
| O:4/0 |
+-----[ ]------+

O:4/0
--------[ ]-------------------------------------------------+-------T:4/0-------+-|
| TON |
| |
| base 1 |
| pre 300|
| acc 0 |
+-------------------+

T4:0 0:4/1
--------[ ]--------------------------------------------------------------( )-----
TT

Cannot toggle or change state in bit table for the input I:1/0
I appreciate all of your help guys. Let me know if I need to furnish anymore information to you regarding the program.
Thanks

Wow. That didnt work at all. Let me see what else I can do