[HELP] Quantum PLC DO Point

Hello Everyone!

So i'm having a Problem Here. There's an Output Point which is Located on a Remote IO Drop, that isn't Working. I can't Solve the Problem alone that's why i Posted here in this Forum, Hoping that someone could help me out.

So Here's the Scenario:
I've had this Logic on my Program That is working really fine. it's just that this one Digital Output that doesn't get energized even if the Rung which it is Located gets True, While the other Output Bit(for Simulation) which is Placed Parallel on this Digital output Bit gets Energized. (i will Put some screenies here for you guys to see the problem)
This Digital output Bit ONLY get energized when i Force its Value to 1.

So here are some solutions that i have already did, but to no luck nothing had worked.
-Delete and then Remake the Variable and Address.
-Renamed the Variable.
-I did put this on a Rung with only an Open Contact then Run it and Toggled the Contact.
-Placed the Variable on other Rung Output with the Same Logic(ex. run command for Motor 1 -> Motor 2).
-Swapped the Address of those 2 Outputs Mentioned above, the Defective Output on the Rung finally got Energized but the Good one got Defective now.(just Tried doing this)

And here are the Solutions that have worked but isn't Advisable.
-Changed the Address of the Variable.
This is the only thing that have worked but would be the last option that we will chose since it will be a lot of work changing all the Documents and Wiring Designs that have been Already Made.

Here are some Other infos that you might ask for:
PLC CPU: 140 CPU 671 60
RIO: 140 CRP 93X 00
DIO: 140 DRC 830 00 (this is where the Bad Output Address is)
Software: Unity Pro XL
-This Program is still on Testing stage on the Field, that's why we're having problems like this.
-I'm sure that no other tags are overlapping with this. and only this Rung is Writing a Value on it, no Other Rung.
-It's not a Logic Problem, there is another Ladder with an identical Logic that work really Fine. i don't Know if there are some settings that i need to configure in the PLC to clear this Problem.
-I Don't have any Proper Training on this Software and Hardware, i just studied this on my own with some knowledge of other PLC Program and hardwares.
-I'm not the one who developed the Program, i just Modified some of it since the Original Programers are already Ended their contract and they didn't turnover this program to me. i just explored these Program and it came to the point that i'm already the one maintaining it. so i hope you guys would understand my condition.

i think i have given all of the Info that you guys might ask and not. but you could still ask me for some info that you couldn't understand. i will be willing to help you so you could help me better.

Here is the Screenshot of the Said Output:


Here is the Screenshot of the Output on Forced Condition:


And here is the Variable Properties:

Are you sure there are not other code with this coil assigned. The only time i have seen something similar is in a case where a Output was written to in multiple rungs.

Have you croschecked if something is not writeing to the word/bit?

@RheinhardtP

Yup, already did that, i've searched the Bit and all of it's uses, i found 2 results the other one is Used as Read, and the one posted above is the only ladder that Writes value on that tag.

EDIT: i also Deleted that Bit in the Program to ensure that no other ladder is using that Bit, after changing the Bit of the 2 results that i have found, after compiling, i got no error. That means only the 2 uses of this Bit are the one that i have checked.

To restate what Rheinhardt asked:

RheinhardtP said:

Have you croschecked if something is not writeing to the word/bit?

Click to expand...

Is the PLC on a network? Perhaps something external is turning the output OFF? HMI, remote PLC, etc.?...



-Eric

Eric Nelson said:

To restate what Rheinhardt asked:Is the PLC on a network? Perhaps something external is turning the output OFF? HMI, remote PLC, etc.?...



-Eric

Click to expand...

Thanks for the tip Eric, Yeah, its on a Network, with an HMI and 2 other PLC units. but i think the problem is not with the network, because right now i'm testing it with only This PLC Hardware online, and the other PLC and HMI are not connected. Plus we don't control the I/O directly from the HMI.

But yeah i will give it a try, i will still check the HMI program.

Up!

Good day,

I have the same thought as your other responders, something else is writing to the output in question.

You responded "Yup, already did that, i've searched the Bit and all of it's uses, i found 2 results the other one is Used as Read, and the one posted above is the only ladder that Writes value on that tag.

EDIT: i also Deleted that Bit in the Program to ensure that no other ladder is using that Bit, after changing the Bit of the 2 results that i have found, after compiling, i got no error. That means only the 2 uses of this Bit are the one that i have checked."

I see it used 3 times, as shown in your properties window.




And here is the Variable Properties:
[/quote]

Where is the 3rd use?

Dan.

Oh Hi Dan!

I'm sorry, i forgot to mention that one, the other use is for the animation Table. we used to monitor Values from there.