Pls help!!How to set a value from hmi :(

What's up guyz.. I need help desperately from a pro.

working with an slc 503 and an ez-touch hmi screen.
I would like to be able to set a value from my hmi screen to increase and decrease a pressure value in my ladder logic..

What I need is help on the logic part.. Where do I start!!

It's an analog signal which is being read by an scp instruction
And then I have an grt instruction which then turns on my output..

In reality if I could increase and decrease source B in my grt instruction from my hmi screen I will be the happiest man alive and I WILL JOIN THE VIP MEMBERS SECTION..even if I have to pay

Please help me somebody

In you SCP instruction you can use an N7:X in place of a fixed number. Then create a tag in the EZ-Touch that points to the N7:X register in the SLC. Use a numeric input box on the EZ-Touch screen that references the tag you created. Now you can change the number on the fly.

I assume that the screen is already talking to the CPU
you need to setup an integer tag to say N9:0 or similar or N7:x as above
if the screen in not directly compatable then check the documentation for the modbus info

as far as joining - please do.
I did not pay to get answers I paid to support Phil Melore who runs the site and has done so since it's inception.

My apologies gentlemen I failed to mention that I am using I:4/6 as an input in my scp instruction and my output is f8:2 if that helps.
And source A of my grt instruction is f8:2 aswell..


Thank u very much and I will support

You can use an F8:X register if you need to use floating point. Integers are a little easier to deal with though. Just point your TAG in the EZ-Touch to the register that you are using to scale by in your SCP instruction.

Lets make make sure I understand you.

You have an analog input wired to slot 4 channel six, and you are taking the value from address I:4.6 and scaling that to a pressure. Then you are comparing the input pressure to an adjustable setpoint and if it is greater than that setpoint you want to turn on an output.

If that is correct then don't change anything with the SCP instruction.

Change the GRT instruction source B parameter to an integer address, N7:X where X is any free register. Program the EZTouch to write a pressure setpoint value to address N7:Y where Y is another free register. Use a different address so that you can range check N7:Y to make sure it is not over or under range. After you do the range check then move N7:Y to N7:X.


GRT N7:Y maximum_value MOV maximun_value N7:Y
LES N7:Y minimum_value MOV minimum_value N7:Y
MOV N7:Y N7:X
GRT scaled_pressure N7:X OTE output

It says " invalid direct file offset" when I use either n9:x or f8:x

Yes sir Alaric you are correct!
I am trying out ur logic..
Would I be asking too much if I asked it to perhaps
Send me the logic via email.. I am an idiot and still learning
[email protected]

Pls and thank you .. It's ok if u can't

When I change source B to n7:x in my grt instruction it says that I have an invalid direct file offset

Look at this example.

In the first rung input I:4.6 is scaled to 0 to 100 pressure units (this is an example only, your scaling is almost certainly different) and the scaled result is put at F8:0.

The EZtouch terminal writes the operator entered setpoint to N7:1 (you can use whatever address you want, N7:1 is just for the example). In my example, the values the operator can enter are between 50 and 100. If the operator enters any value outside that range the value is fixed by the PLC program so that it is inside the range. The second and third rung in the example do this.

Now once the operator entered value has been range fixed, the operator entered value is moved from N7:1 to F8:1 by the fourth rung.

In the fifth rung, if the pressure value at F8:0 is greater than what was written to F8:1 then the output is turned on.

jk1981 said:

When I change source B to n7:x in my grt instruction it says that I have an invalid direct file offset

Click to expand...

Are you entering N7:x or are you substituting the number of a free address for the x? N7:x means I don't know what address you are using and you are supposed to put that address in place of the x.

I don't know who u are Alaric but I love u man.. Like I said I'm an idiot.. I will try that example right now.. Your fking amazing

Your a good man Alaric.. I've got it working

Your a good man Alaric.. I've got it running