P_AIN.FAIL.Val_MinToUnshelve Comparison

[psgama]

Hello all,

I'm trying to come up with an elegant solution to check an Array of Values to see if they are greater than zero but less than 15

My Array size is 820, so P_AIN[820]

This is what I'm trying to accomplish.


For i = 1 to 820

if P_AIN.FAIL.VAL_MinToUnshelve > 0 and P_AIN.FAIL.VAL_MinToUnshelve <=15 THEN
ALARM_SHELVE_EXPIRY_ALARM = TRUE
Exit For
End if
Next i
​

Anyone have an elegant way to implement this in RSlogix5000 using structured text or otherwise?

 

[pasbra]

Hello all,
For i = 1 to 820

if P_AIN.FAIL.VAL_MinToUnshelve > 0 and P_AIN.FAIL.VAL_MinToUnshelve <=15 THEN
ALARM_SHELVE_EXPIRY_ALARM = TRUE
Exit For
End if
Next i
​

I think there are error of syntax, but the methode is corrrect. Alarm is not remind to False with this code...

For i = 1 to 820 Do
 if P_AIN[i].FAIL.VAL_MinToUnshelve > 0 and P_AIN[i].FAIL.VAL_MinToUnshelve <=15 THEN
  ALARM_SHELVE_EXPIRY_ALARM = TRUE;
 End if;
End For;
[/INDENT]

 

[drbitboy]

It may no longer be true, but I think less than is slightly faster than less than or equal to, so less than 16 is an alternative equivalent to less than or equal to 15

There is also the A-B LIM instruction, but I do not know if it is available in ST.

I don't think a bitwise AND will help

 

[drbitboy]

Alarm := FALSE;

i := 1;

While not alarm and i < 821 do

  Alarm := Alarm or (array > 0 and array  < 16);

  i := i + 1;

End_while;

?

 

[psgama]

Thanks for the responses.
It looks like I won't actually be able to to implement what I was after this way, as the AOI internal tags weren't made visible external to the routine.

I can reference them in FactoryTalk View Studio and Kepware just fine, however when I try to use the FAIL.VAL_MinToUnshelve within RSlogix 5000 it reports an Unknown Tag Element.

 

[Phrog30]

You can't edit the AOI?

 

[pasbra]

Alarm := FALSE;

i := 1;

While not alarm and i < 821 do

  Alarm := Alarm or (array > 0 and array  < 16);

  i := i + 1;

End_while;

?

Always drbitboy have a very good optimisation code! Thank you for your experience!

 

[JeremyM]

Alarm := FALSE;

i := 1;

While not alarm and i < 821 do

  Alarm := Alarm or (array > 0 and array  < 16);

  i := i + 1;

End_while;

?

Wouldn’t this work?

Alarm := FALSE;
i := 1;
While not alarm and i < 821 do
  Alarm := (array[i] > 0) and (array [i] < 16);
  i := i + 1;
End_while;

 

[psgama]

You can't edit the AOI?

Plant is online, I don’t believe Rockwell allows AOIs to be edited while online. Next scheduled Shutdown is in 5 years.

 

[drbitboy]

Wouldn’t this work?

Alarm := FALSE;
i := 1;
While not alarm and i < 821 do
  Alarm := (array[i] > 0) and (array [i] < 16);
  i := i + 1;
End_while;

yes, +1 .

And by switching to a REPEAT-UNTIL Alarm or i > 820 we can drop the initial assignment of Alarm.

 

[drbitboy]

Or maybe it's not a good idea ... you better post it again

 

[JeremyM]

lol

Same thought for me 83% of the time I’m already downloading.