Hi There I just finish putting together a CPM1A with a Nt2S HMI, my goal was to display Alarm msg on a screen, wich I was able to do. But can anyone tell me why is it I had to set my MOV to DM100 like this:

Alarm #---->Move to DM100
000--------->&0
001--------->&2
002--------->&4
003--------->&8
004--------->&16
005--------->&32
----------------------------
010--------->&1024

Why can I just MOV the alarm coresponding Number to DM100?

Thank you for your Help.

Alarms in NT2S and NT3S react on a bit setting.
In the tag you define as alarm register ( in your case DM100) the bits when an alarm should be displayed.

So DM100.00 is high it activates alarm 000
DM100.15 is high it activates alarm 15

So you do not need to move the value but you have to trigger the alarmbit of the alarm that needs to be displayed.

with the move you can also only display only 1 alarm.

In the key tasklist screen you can select key specific task for define keys to act on the alarm screen.

regards,

OK,... this make more sense now...I will try this tonight and change all my move with DM100.00 to DM100.10 ouput which should give me the coresponding alarm ON.
Thank you MPM.

On a side note, why wouldn't it be possible to set any combination of multiple bits at once by setting the equivalent hex value?

It is offcourse possible but you will have always take care of the alarms that are already present.

If you have 10 alarms defined you have to define each combination possible when writing values to the alarm register.

If an alarm always comes alone it should be not an issue at all.

regards,

No need to write every combination, you could just program 16 alarm contacts directly to 16 coils of the same IR word, then do a constant move of the IR word value to the DM word ? Or am I missing something...

Hi PdL,

No you are not missing something. We are saying exactly the same only you use IR coils as intermediate.
As the example given was directly for DM100 so I proposed to use the DMcoils same as you do with IR coils. Now you do not need to move the IR all the time to DM.

regards,

Hi MPM, I thought is isn't possible to adress a DM coil directly in ladder ? Don't get me wrong, I just like to understand this as I use quite a lot NT2S myself and usually use any memory area that can be directly adressed as coils as alarm registers like LR or IR.

Hi PdL,

You are absolutely right.
You can toggle bits in the view , windows watch part but indeed DM on coil level can not be programmed.

Srry,

No worries, thanks for clearing up our misunderstanding . I hope we haven't confused PLC4me

No It is all right. I am sorry I did keep up with you guys, but I got tie up trying to setup comm with these NT2S unit. I use the the IR coil solution creating 16 alarm register that is more then I need, was lookin for 5 alarms.

thank you all for helping me. You guys or so good that I am going to ask you a new question, please look for my question about "downloading Firmware to NT2S"

LOL you sure stirred up the discussions with your questions