I don't know if this function exist.

Hi,

I am not really sure but for S7-1200/1500 there are instructions called IN_RANGE and OUT_RANGE - perhaps this helps you?!

Check this:

https://docs.tia.siemens.cloud/r/en-us/v20/fbd-s7-1200-s7-1500/comparator-operations-s7-1200-s7-1500/in_range-value-within-range-s7-1200-s7-1500

Regards,

Towome

Gabriel_W

I would like to know if there is a function that would activate a BOOL variable when the recipe value has a deviation of plus or minus 3.

Deviation from what? Its value from previous scan? Its value from 3 days ago? Or from what?

"Function Unknown" becomes an FC you create.

Let's call it Function PlusMinusThree (FC).  Refer to below pseudo code (SCL-like).

Function NotPlusMinusThree
VAR INPUT
  newValue : Int
  oldValue : Int
END VAR

RETURNS : BOOLEAN  // if | newValue - oldValue | > 3.0 returns TRUE
 
BEGIN
  #NotPlusMinusThree := FALSE;  // prevents compilers warnings

  IF ABS(#newValue - #oldValue) > 3 THEN
    #NotPlusMinusThree := TRUE;
  END_IF;

END

Then your call would look something like this: 

| "TagIn_1"  "NotPlusMinusThree"("TagIn_1")    "TagOut" |

|-----|  |------------|   |-------------------(   )-----|

|                                                                     |

Otherwise, you might consider making the above an FB so it can *remember* the last value for you automatically.

Function Block NotPlusMinusThree
VAR INPUT
  newValue : Int
END VAR

VAR OUTPUT
  RtnValue : BOOLEAN  // if | newValue - oldValue | > 3.0 returns TRUE
END VAR

VAR STATIC
  init : Bool
  oldValue : Int
END VAR

BEGIN
  #RtnValue := FALSE;  // prevents compilers warnings

  IF NOT #init THEN
    #oldValue := #newValue
    #init := TRUE
  END_IF

  IF ABS(#newValue - #oldValue) > 3 THEN
    #RtnValue := TRUE
  END_IF

  #oldValue := #newValue  // remember value for next call to same FB instance

END

Then your call would look something like this:

|              TagIn_1_NPM3_iDB               |
|  TagIn_1      --------------                |

|---|  |--------|EN          |-               |
|               |    RtnValue|-tTagIn1_PM3    |
|               |newValue    |                |

|               --------------                |
|                                             |
| tTagIn1_PM3                         TagOut  |
|---| |-----.......................---(   )---|

Forgive me for my poor skills drawing this. 

Gabriel_W

Hello everyone,

I'm working on an ET-200SP with TIA PORTAL V18 software.

The recipe system sends values to INT variables. Its variables therefore regularly change value.

I would like to know if there is a function that would activate a BOOL variable when the recipe value has a deviation of plus or minus 3.

For example :

| "TagIn_1"  "Function Unknown"   "TagOut" |

|-----|  |------------------|   |------------------(   )-----|

|                                                                     |

This unknown function would have, for example, 3 EN inputs, the first of which would be “Variable INT - 3”, the second “Variable INT” and the third “Variable INT +3”.

For example, the “TagOut” variable would be set to 1 when the deviation is reached.

Does this function exist?

Thank you in advance for your answers.

Translated with DeepL.com (free version)

OT

0_Einstein

#NotPlusMinusThree := FALSE;  // prevents compilers warnings

IF ABS(#newValue - #oldValue) > 3 THEN
#NotPlusMinusThree := TRUE;
END_IF;

Functionally equivalent:

#NotPlusMinusThree := ABS(#newValue - #oldValue) > 3;

OT: I am well aware, however, given the level of sophistication of the topic poster, I did not want to introduce too much SCL confusion on possibly their first time seeing SCL.
I prefer adding parens around those BOOL blocks, so I might write it like this (and ignore the SCL warnings about the parens not being necessary:

#NotPlusMinusThree := (ABS(#newValue - #oldValue) > 3);

To more seasoned folks such as yourself, parens are wasted.  However, I work with people who embrace LAD and avoid SCL.  Anything I can do to make it easier to comprehend without adding comments it worth a couple extra (parens).

jacek d

OT

0_Einstein

#NotPlusMinusThree := FALSE;  // prevents compilers warnings

IF ABS(#newValue - #oldValue) > 3 THEN
#NotPlusMinusThree := TRUE;
END_IF;

Functionally equivalent:

#NotPlusMinusThree := ABS(#newValue - #oldValue) > 3;