HC 900 Range FB

[_V_]

Hey guys, what is the function block that you guys use for range value ?
I want to turn off a valve when a analog value is between 2 and 50, what FB do you guys use ?
I am using hc900 honeywell PLC.

Thank you !

 

[drbitboy]

Hey guys, what is the function block that you guys use for range value ?
I want to turn off a valve when a analog value is between 2 and 50, what FB do you guys use ?
I am using hc900 honeywell PLC.

Thank you !

ORing the results of an HMON (cf. here) and an LMON would probably be the best from a "what is this doing?" aspect three months from now, and so is probably the best option.

HLLM (cf. here) is another optionl it would require ANDing the H and L output pin results, but might read nicely.

DCMP cf. here; i.e.

• Y = input analog value
• IN1 = 2
• IN2 = 50
• Internal configuration
  • Plus Deviation = 48
  • Minus Deviation = 48

I think that works. It's a little obscure, so it's good for Code Golf but I am not sure it belongs in production.

 

[_V_]

Can you explain how ?

I try to use the HLLM and when I put the limits it didn't range nothing.
And in the O Ring I put between 2 and 28, then 32 and 95 and it didn't turn off.
What do I want is, I have a valve and it gives me a value, and when the value is 0 25 30 or 96 it turns on a variable, but when is like 2-28 and 32-95 it turns off the signal to the variable. So I think I have to put a FB that when in that range it turns off.

 

[_V_]

https://ibb.co/0XYrtGB

In that link is what I did, but the output is 28.
And that FB it should be off, because my valve at 0% turns on the variable.

 

[drbitboy]

This is not clear.

Originally you wrote that values between 2 and 50 would assign a value of 0 to a bit ("turn off a valve"), so presumably values

• EITHER less than 2
• OR greater than 50

will write a 1 to that bit.

But now you write

when the value is 0 25 30 or 96 it turns on a variable, but when is like 2-28 and 32-95 it turns off the signal to the variable.

25 => write a 1 to the bit ("turns on"), but 25 is in the range 2-28 => write a 0 to the bit ("turns off").

0, 30, and 96 are all outside those ranges, so they would write a 1 to the bit ("turn on").

Is the 25 a typo?

 

[drbitboy]

off = (v > 2 AND v < 28) OR (v > 32 AND V< 95)



on = NOT off



De Morgan:



= NOT (     (v > 2   AND       v < 28)   OR        (v > 32   AND       v < 95))



=     (NOT  (v > 2   AND       v < 28))  AND (NOT  (v > 32   AND       v < 95))



=     ((NOT (v > 2)) OR  (NOT (v < 28))) AND ((NOT (v > 32)) OR  (NOT (v < 95)))



=     (      v < 2   OR        v > 28  ) AND (      v < 32   OR        v > 95))



Associative property [(a OR b) AND c => (a AND c) OR (b AND c)]:



=     ( v < 2 AND (v < 32 OR v > 95)) OR ( v > 28 AND (v < 32 OR v > 95))



Associative property again, within each term on either side of the central OR:



=     ((v < 2 AND v < 32) OR (v < 2 AND v > 95)) OR ((v > 28 AND v < 32) OR (v > 28 AND v > 95))



Drop redundant parentheses:



=      (v < 2 AND v < 32) OR (v < 2 AND v > 95)  OR  (v > 28 AND v < 32) OR (v > 28 AND v > 95)



       ( true if v < 2  )    ( cannot be true )      ( cannot simplify )    ( true if v > 95  )



=       v < 2             OR                         (v > 28 AND v < 32) OR             v > 95



= v < 2 OR (v > 28 AND v < 32) OR v > 95





In HC900 FB:



      ______

     [LMON  ]

   v-[X  OUT]-------------------------+

   2-[Y     ]                         |

      ------                          |   _______

      ______                _______   |  [4OR    ]

     [HMON  ]              {2AND   ]  +--[    OUT]---

   v-[X  OUT]--------------[    OUT]-----[       ]

  28-[Y     ]           +--[       ]    -[       ]

      ------            |   -------   +--[       ]

      ______            |             |   -------

     [LMON  ]           |             |

   v-[X  OUT]-----------+             |

  32-[Y     ]                         |

      ------                          |

      ______                          |

     [HMON  ]                         |

   v-[X  OUT]-------------------------+

  95-[Y     ]

      ------





Or, to replace the HMON/LMON pair for 28<v<32 with an HLLM:

      ______

     [LMON  ]

   v-[X  OUT]-------------------------+

   2-[Y     ]                         |

      ------                          |

                                      |

        v                             |   _______

      __|___                _______   |  [4OR    ]

     [HLLM  ]              {2AND   ]  +--[    OUT]---

     [(32) H]--------------[N   OUT]-----[       ]

     [(28) L]--------------[N      ]    -[       ]

      --+---                -------   +--[       ]

        |                             |   -------

     (unused)                         |

      ______                          |

     [HMON  ]                         |

   v-[X  OUT]-------------------------+

  95-[Y     ]

      ------

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